Orwell Astronomical Society (Ipswich)

Home Events

Allsky Images, 23 June 2018 - 03 September 2021

Introduction

In 1978, OASI member Alan Smith started running an all-sky camera. Unfortunately, a combination of slow optics and increasing levels of light pollution meant that, by 1986, the camera was producing few good results and Alan ceased operations.

Fast-forward 32 years to 2018 and imaging technology has made huge strides: chemical film is a distant memory, imaging is all-electronic and sensitivities are vastly superior to those possible with the earlier equipment. Alan decided to reprise the all-sky camera using modern technology. Later, James Appleton and Martin Richmond-Hardy also began running all-sky cameras. Capturing images from different locations enabled triangulation of meteor trails to estimate the trajectories of the bodies through the Earth's atmosphere.

A selection of images from the cameras is below. The cameras themselves are described at the bottom of the page.
 

Details

Image

10 Jun 2021. A fireball in Pisces displays multiple flares.

Top: Alan. 00:21:24 - 00:21:54 UT, single 30 s exposure. ZWO ASI294 camera with 4.5 mm Sigma fisheye lens, f2.8, gain 300, colour, rotating shutter.

Next: Alan. Corresponding single 60 s exposure. Canon 1100D with "LensBaby" 5.8 mm, f3.5 lens (stopped down to f5.6), colour, no LC light gate.

Next: Martin. 20 s exposure. ZWO ASI120MM camera with ZWO fisheye lens, f1.2, gain 50, B&W. The camera cpatures only the initial part of the trail

Bottom: James. 00:21:25 - 00:21:55. Single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20210910_002154_fireball_AJS_ASI194_959.jpg
20210910_fireball_AJS_C1100D_1312.jpg
20210910_002138_fireball_MRH.png
20210910_002155_fireball_JMA.jpg
A very bright fireball imaged through clouds. Zooming-in shows widely spaced breaks caused by the rotating shutter suggesting a high speed event. The fireball was also captured by cameras of the Dutch Meteor Society.

Alan. 03 Sep 2021, 03:38:06 - 03:38:36 UT, single 30 s exposure. ZWO ASI294 camera with 4.5 mm Sigma fisheye lens, f2.8, gain 300, colour, rotating shutter.

20210903_033836_fireball_AJS_910.jpg
10-16 Aug 2021.
Observations of Perseid meteor shower 2021.
Noctilucent cloud is visible as a thin ribbon-like blue/white cloud just above the tree line to the north (top of image).

Alan. 09 Jun 2021, 21:37 UT, single 2 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, no LC light gate.

20210609_2137_NC_AJS_6717.jpg
07 Jun 2021. A satellite passing through Cygnus leaves a distinctive trail with periodic bright dots. The latter are caused by the rotation of the body periodically bringing reflective panels into alignment to reflect sunlight.

Top: Alan. 23:54:52 - 23:55:52 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, no LC light gate.

Bottom: James. 23:54:29 - 23:55:29. Two consecutive 30 s exposures. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20210607_235552_satellite_AJS_6314.jpg
20210607_235559_satellite_JMA.jpg
07 Jun 2021. Occasionally, many Starlink satellites can create flares in a short period of time in the same area of the sky. The following images, taken over a period of five minutes, show trails from at least 16 Starlink satellites.

Top: Alan. 23:21:52 - 23:26:52 UT, five consecutive 60 s exposures. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, no LC light gate.

Bottom: James. 23:21:33 - 23:26:37. Ten consecutive 30 s exposures. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20210607_232652_Starlink_AJS_6283.jpg
20210607_232637_Starlink_JMA.jpg
07 Jun 2021. US military intelligence satellite NOSS3-6A leaves a double trail near Spica. The satellite is the sixth in a series of third generation US Navy Ocean Surveillance Satellites (NOSS). The satellite comprises two co-orbiting vehicles.

Top: Alan. 22:59:31 - 23:01:31 UT, two consecutive 60 s exposures. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, no LC light gate.

Bottom: James. 22:59:16 - 23:02:18. Six consecutive 30 s exposures. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20210607_230131_NOSS3-6A_AJS_6262.jpg
20210607_230218_NOSS3-6A_JMA.jpg
31 May 2021. A fireball streaks through Capricornus.

Top: James. The fireball passes between α and β Capricorni. 01:44:01 - 01:44:31 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 160, colour.

Middle: Alan: 01:44:21 - 01:44:28 UT. Video captured by an "eyeball" camera. While travelling through the atmosphere, the ionisation of the fireball and atmosphere produced a radio reflective layer which reflected distant radio transmissions back towards the Earth, enabling them to be received by suitable equipment. Chris Albins in Ipswich monitored reflections from a radio beacon at Dourbes in Belgium (the beacon is primarily used by the Belgian BRAMS network of receivers.) Chris synchronised his recording with Alan's video recording and added it as a sound track. (Note that the time in the the video is BTS rather than UT.)

Bottom: trajectory calculated by members of the Dutch Meteor Society. The object entered the atmosphere at an altitude of 96.4 km travelling at about 15.8 km/s to the west of Arras (France). It reached a photometric magnitude of -10.8 (the full moon measures around -12.7) dropping to an altitude of 80.0 km south of Lille (France) before it entered "dark flight" and became invisible.

20210531_014431_fireball_JMA.jpg

20210531_track.jpg
23 Apr 2021. The fireball cameras captured two Lyrids close to the eastern horizon, the first in Aquarius and the second in Equuleus. Members of the Dutch Meteor Society also observed the meteors, and triangulated the trajectory of the first as follows. The object entered the atmosphere at 112 km altitude at a speed of 48 km/s. It descended through the atmosphere, reaching a peak brightness of magnitude -11.9 and began dark flight at an altitude of 71 km altitude on the Dutch-German border near to Vlodrop.

Top: Alan. 02:49:01 - 02:50:01 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 400, colour, no LC light gate.

Second: James. 02:49:16 - 02:49:46 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 130, colour.

Third: Alan. 03:04:59 - 03:05:59 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 400, colour, no LC light gate.

Bottom: James. 03:04:58 - 03:05:28 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 130, colour.

20210423_025001_meteor_AJS_1550.jpg
20210423_024946_meteor_JMA.jpg
20210423_030559_meteor_AJS_1565.jpg
20210423_030528_meteor_JMA.jpg
06 Apr 2021. A fireball over south Wales creates a trail visible from Ipswich on the western horizon. The trail has a light green tinge. The event was captured by observers from as far west as County Clare, Eire. IMO report of the event.

Top: Alan. 01:18:41 - 01:19:41 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f4.0, ISO 800, colour, no LC light gate.

Bottom: James. 01:18:47 - 01:19:02 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20210406_011941_fireball_AJS_8492.jpg
20210406_011902_fireball_JMA.jpg
A fireball in Hydra seen behind cloud, with much background glow from the Moon, just past full nearby in Virgo (lunar phase 99%, waning).

Observers from the French "FRIPON" network of fisheye video cameras also observed the object, and concluded that its flight was over the English Channel, approximately as follows. It entered the atmosphere at 85 km altitude at a velocity of 29 km/s and with a photometric magnitude of -2.5. Maximum brightness of magnitude -7.5 was at 65 km altitude whilst travelling at around 28 km/s. The object "burned out" and began dark flight at about 45 km altitude travelling at 24 km/s.

Observers from the IMO also logged this event, and calculated a slightly different trajectory, using just eye witness reports.

Alan. 29 Mar 2021, 23:09:32 - 23:10:32 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f4.0, ISO 800, colour, no LC light gate.

20210329_231032_fireball_AJS_5945.jpg
A fireball streaks past Arcturus.

Top: Alan. 21 Mar 2021, 22:25:43 - 22:26:32 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, no LC light gate.

Bottom: the fireball was also observed across the Benelux countries. Members of the Dutch Meteor Society reduced the observations to estimate the trajectory of the object. It entered visible flight through the atmosphere at an altitude of about 85 km travelling at about 25 km/s, and entered dark flight, becoming invisible, at an altitude of about 35 km. Its maximum brightness was approximately magnitude -12.5 at an altitude of 48 km. (It was a bright event!)

20210321_222643_fireball_AJS_2570.jpg
20210321_track.jpg
13 Mar 2021. A fireball in Leo is visible through thin cloud.

Top: Alan. 19:37:55 - 19:38:55 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, no LC light gate.

Bottom: the fireball was also imaged from Oostkapelle (Netherlands). Using the two images, members of the Dutch Meteor Society reduced the observations to estimate the trajectory of the object. It became visible at an altitude of 74 km and descended at a velocity of 16  km/sec, entering dark flight and becoming invisible at an altitude of 38 km. The maximum photometric magnitude was -5.1, at an altitude of 43 km, so the object was not spectacularly bright. The path of the fireball ran directly between the two observing stations, providing ideal circumstances for triangulation.

20210313_193855_fireball_AJS_0054.jpg
20210313_track.jpg
Nine trails from satellites in nearly identical orbits run close together through Lyra, Cygnus and Vulpecula in a time exposure image. Although identification is not certain, they are believed to be members of Starlink launch L16, launched on 20 January 2021.

Alan. 04 Feb 2021, 05:03 - 05:12 UT, stack of nine 60 s exposures. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20210204_0512_Starlink_AJS.jpg
A constellation of Starlink satellites coming to approximately the same alignment in Hercules (near λ Her) creates a cluster of short, bright uneven tracks in a time exposure image. Starlink satellites crossing the relevant area of sky within the appropriate time window were the following: 1835, 1883, 1944, 1832, 1851, 1882, 1798, 1908, 1893, 1899, 1929 and 1943.

James. 09 Jan 2021, 06:29:56 - 06:32:28 UT, stack of five 30 s exposures. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20210109_063228_Starlink_JMA.jpg
06 Dec 2020. An unusual satellite trail in Cygnus. The many bright dots are likely caused by a rapidly spinning structure. A close-up of the trail from the two below images, shown as an inset in the lower image, shows essentially zero parallax, indicating that the object is at a considerably higher altitude than is possible for a meteor.

Top: Alan. 17:54:35 - 17:55:35 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 17:54:32 - 17:55:32 UT, stack of two 30 s exposures. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201206_175535_satellite_AJS_6913.jpg
20201206_175532_satellite_JMA.jpg
A very bright fireball in Ursa Major. The LC (liquid crystal) shutter chops the image to give an idea of the speed of the object and duration of visibility. The trail shows at least 30 "breaks" indicating a duration of at least three seconds. The image is seriously compromised by the very bright full moon and incoming fog.

Alan. 28 Nov 2020, 20:10:27 - 20:11:27 UT, single 60 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20201128_201127_fireball_AJS.jpg
23 Nov 2020. A meteor in Auriga and Gemini displays a double terminal flare.

Top: Alan. 22:33:36 - 22:34:33 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 22:33:13 - 22:33:46 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201123_223433_meteor_AJS_0153.jpg
20201123_223346_meteor_JMA.jpg
23 Nov 2020. A fireball in Pisces.

Top: Alan. 00:48:22 - 00:49:19 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 00:49:03 - 00:49:33 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201123_004919_fireball_AJS_9477.jpg
20201123_004933_fireball_JMA.jpg
20 Nov 2020. A fireball in Virgo. The object was also observed by Benelux observers.

Top: Alan. 05:55:31 - 05:56:28 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 05:56:07 - 05:56:37 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201120_055628_fireball_AJS_8180.jpg
20201120_055637_fireball_JMA.jpg
20 Nov 2020. A fireball in Pisces.

Top: Alan. 01:19 - 01:20 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 01:20:03 - 01:20:33 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201120_0120_fireball_AJS_7908.jpg
20201120_012033_fireball_JMA.jpg
The glow of a bright fireball is visible even through dense cloud.

Alan. 19 Nov 2020, 04:24:11 - 04:25:08 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20201119_042508_fireball_AJS_7283.jpg
19 Nov 2020. A bright Leonid meteor.

Top: Alan. 01:55:08 - 01:56:05 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.


Bottom: James. 01:55:27 - 01:55:57 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201119_015605_meteor_AJS_7136.jpg
20201119_015557_meteor_JMA.jpg
A Leonid fireball creates an ionisation trail. The Leonid meteor shower occurs when the Earth passes through the dust trail created by comet Tempel-Tuttle. Leonid meteors are typically very fast, with an approach velocity of approximately 72 km/s. The video shows a bright flash lasting for about ½ second, leaving a slightly orange/brown ionisation train which drifts slowly up and to the left. The ionisation train is created when atoms of the atmosphere and meteor itself are ripped apart by the tremendous heat generated by friction as the object enters the atmosphere. Winds in the upper atmosphere cause the train to twist and disperse over a period of around 15 minutes. Observation was hampered by light cloud.

Alan. 18 Nov 2020, 03:23 UT, video constructed from 26 exposures of 57 s duration. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20201118_Leonid_AJS_6423.gif
A sporadic meteor in Perseus.

Alan. 16 Nov 2020, 05:46:51 - 05:47:48 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20201116_054748_meteor_AJS_5774.jpg
A fireball in Cetus. The object was also imaged by cameras in Oostduinkirke and Ieper (Belgium). Members of the Dutch Meteor Society reduced the observations to give the following description of the trajectory: the meteor entered the atmosphere at about 80 km altitude and, after reaching a velocity of around 29 km/s, was seen at about magnitude -4, finally entering the dark phase of flight at about 45 km altitude. The object was a member of the Taurid group of meteors. The green colour of the meteor trail is genuine and probably caused by the ionisation of nickel on the surface of the object.

Alan. 12 Nov 2020, 22:20:40 - 22:21:37 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20201112_222137_fireball_AJS_4701.jpg
07 Nov 2020. A fireball in Puppis. The object was also observed by members of the Dutch Meteor Society, who reported as follows:

Top: Alan. 03:39:23 - 03:40:20 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 03:40:07 - 03:40:37 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201107_034020_fireball_AJS_2850.jpg
20201107_034037_fireball_JMA.jpg
The night of 24-25 October did not start promisingly, and dense cloud and rain persisted until almost 04:00 UT. However, conditions then improved sufficiently to reveal a spectacular fireball in Cetus. The event was also observed by meteor observers in Pleumeur-Bodou (France), Honiton, Manchester and Cardiff. (Note: the apparent dimples in the image are raindrops on the dome of the camera.)

James. 25 Oct 2020, 04:06:28 - 04:06:58 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

20201025_040658_fireball_JMA.jpg
A suspected meteor in Cassiopeia.

Alan. 10 Oct 2020, 19:12 - 19:13 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20201010_1913_meteor_AJS_0378.jpg
22 Sep 2020. An Earth-grazing meteor leaves a trail stretching almost from horizon to horizon. The object, thought to be approximately one centimetre in diameter, briefly entered the Earth's upper atmosphere and bounced off the lower, denser layers without significantly decelerating. Such behaviour is comparatively rare.

Top: Alan. 03:52:48 - 03:54:45 UT, stack of two consecutive 57 s exposures. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Second from top: James. 03:53:21 - 03:54:21 UT, stack of two consecutive 30 s exposures. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour.

The object was also observed by Benelux observers, one of whom, Hans Betlem, analysed the results and reported as follows:

Third from top: meteor path, calculated by Hans.

Bottom: height profile, also calculated by Hans.

20200922_035345_Earth_grazing_AJS_6592.jpg
20200922_035421_Earth_grazing_JMA.jpg
20200922_track.jpg
20200922_height_profile.jpg
12 Sep 2020. A bright meteor in Pegasus.

Top: Alan. 00:25:25 - 00:26:22 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 00:25:44 - 00:26:14 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour. An aircraft trail crosses the meteor track.

20200912_002622_fireball_AJS_1063.jpg
20200912_002614_fireball_JMA.jpg
07 Sep 2020. A meteor in Aquarius, partially obscured by cloud.

Top: Alan. 02:20:46 - 02:21:43 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate. Due to cloud, only the terminal flare of the meteor is visible. By way of compensation, the cloud has caused the formation of a lunar halo!

Bottom: James. 02:21:12 - 02:21:42 UT, single 30 s exposure. ZWO ASI 178MC with Fujinon fisheye lens, f1.8, gain 200, colour. In the subsequent frame, starting at 02:21:42 UT, there is a very short track following the terminal flare, before the object began dark flight. The inset shows, L-R, the meteor trail up to the terminal flare, with a blue line indicating the trajectory, the meteor trail after the terminal flare, with a red line indicating the trajectory, and a superposition of the trajectories, showing that they diverge, suggesting that the post-flare trail is caused by a small piece of debris ejected at an angle to the original trajectory by the explosion which created the terminal flare. It was truly fortuitous that the camera frame changeover occurred immediately after the terminal flare: had it not done so, the post-flare trail would have been lost in the glare of the flare.

20200907_022143_meteor_AJS_8802.jpg
20200907_022142_meteor_JMA.jpg
28 Jul - 13 Aug 2020.
Observations of Perseid meteor shower 2020.
In the dawn twilight, a meteor streaks through Aries and exhibits a terminal flare in Cetus.

Alan. 04 Aug 2020, 03:03:53 - 03:04:50 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20200804_030450_meteor_AJS_8411.jpg
A twin satellite displays trails that are exceptionally widely separated. Alan also recorded the object in an image timed at 01:43 - 01:44 UT, and recorded a similar pair of widely-spaced tracks in Serpens Cauda on 19 July in a frame timed at 22:12 - 22:13 UT.

James. 21 Jul 2020, 01:43:08 - 01:44:29 UT, stack of three consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200721_014439_wide_dual_sat_JMA.jpg
A fireball in Aquila displays three minor flares and a bright terminal flare.

James. 21 Jul 2020, 00:10:24 - 00:10:54 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200721_001054_meteor_JMA.jpg
The ISS (International Space Station makes a spectacular passage through the Summer Triangle (Deneb, Altair, Vega) while comet C2020 F3 (NEOWISE) is visible on the northern horizon.

Alan. 11 Jul 2020, 00:39 - 00:40 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20200711_ISS+C2020F3_AJS_3826.jpg
American twin surveillance satellites NOSS (Naval Ocean Surveillance System) 3-1A betray their presence by a spectacular flare in Hercules. (See also images taken 23 August 2019 and 15 May 2019.) Alan also imaged the flare: there was minimal parallax between the two images, indicating that the satellite was at an orbital altitude of many hundred km. Zooming into the image reveals traces of a secondary track, although it is largely drowned out by the flare.

James. 16 Jun 2020, 23:29:50 - 23:30:51 UT, stack of two consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200616_233051_NOSS3-1A_JMA.jpg
08 May 2020. A meteor through Boötes and Virgo. Unfortunately, considerable glare from a gibbous Moon created a very bright sky, with too few stars visible to attempt to triangulate the trajectory of the body from the two images.

Top: Alan. 23:41:34 - 23:42:32 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

Bottom: James. 23:41:09 - 23:42:09 UT, single 60 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 150, colour.

20200508_234232_fireball_AJS_9141.jpg
20200508_234209_fireball_JMA.jpg
An unidentified object appears as a string of pink dots, with some similarities to the object imaged on 17 Feb 2020 (below). Discussion is ongoing as to what the object could be!

Alan. 23 Apr 2020, 02:41 - 02:42 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20200423_0242_allsky_AJS_4709.jpg
A double satellite trail in the sickle of Leo.

Alan. 10 Apr 2020, 22:29 - 22:30 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20200410_2230_allsky_AJS_1016.jpg
24 Mar 2020. A meteor in Leo.

Top: Alan. 02:31:55 - 02:32:53 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, LC light gate.

Middle: James. 02:32:24 - 02:32:54 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: estimate of the meteor track over the English channel and southern England, descending from 88 km to 40 km.

20200324_023253_meteor_AJS_3292.jpg
20200324_023254_meteor_JMA.jpg
20200324_023254_track.jpg
The ISS (International Space Station) makes a spectacular passage from west to east across the sky.

James. 23 Mar 2020, 19:37:33 - 19:42:07 UT, stack of ten consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200323_194207_ISS_JMA.jpg
A fireball in Cygnus with a terminal flare. The trail exhibits a pronounced green colour.

Alan. 23 Mar 2020, 00:19:27 - 00:20:25 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 1600, colour, LC light gate.

20200323_002025_fireball_AJS_2524.jpg
A rotating satellite creates a trail of bright dots on the boundary between Triangulum and Aries.

James. 20 Mar 2020, 19:18:27 - 19:19:27 UT, stack of two consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200320_191927_allsky_JMA.jpg
A slow-moving satellite leaves a short trail in southern Boötes over a period of approximately two minutes. (The object is visible in all five exposures.)

James. 17 Mar 2020, 00:22:14 - 00:24:45 UT, stack of five consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200317_002445_allsky_JMA.jpg
13 Mar 2020. A bright fireball in Orion, with a terminal flare, is visible behind light cloud. Cloud and lack of stars visible in the vicinity prevented a triangulation from being carried out.

Top: Alan. 19:34:27 - 19:35:25 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, LC light gate. The LC light gate imposed only two breaks in the trail, implying that the object was fast-moving.

Bottom: James. 19:34:17 - 19:34:47 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200313_1935_fireball_AJS_9714.jpg
20200313_193447_fireball_JMA.jpg
12 Mar 2020. A double satellite trail in Monoceros.

Top: Alan. 19:59 - 20:00 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour, LC light gate.

Bottom: James. 19:59:51 - 20:00:51 UT, stack of two consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200312_2000_allsky_AJS_9131.jpg
20200312_200051_allsky_JMA.jpg
In a sky illuminated by a full moon, the ISS passes from Serpens Caput, through Ophiuchus, into Aquila.

James. 09 Mar 2020, 04:20:20 - 04:22:21 UT, stack of four consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200309_042221_ISS_JMA.jpg
First light of the camera with acrylic dome in place of the clock-glass used previously. A streak with an apparent terminal flare passes through Cepheus, but is it unclear whether it is a satellite or a meteor.

Alan. 07 Mar 2020, 04:07 - 04:08 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200307_0408_allsky_AJS_7961.jpg
A bright satellite flare through Hercules.

James. 03 Mar 2020, 04:54:11 - 04:55:11 UT, stack of two consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200303_045511_allsky_JMA.jpg
Part of a very bright meteor trail on the eastern horizon. The trail was also imaged by Benelux observers, but not by Alan (due to obstructions to his view east).

James. 02 Mar 2020, 23:37:37 - 23:38:07 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200302_233807_fireball_JMA.jpg
The passage of a Starlink constellation across the sky. The trail is barely visible due to thin cloud. The complete passage lasted from 05:08 to 05:17 UT.

Alan. 28 Feb 2020, 05:09 - 05:10 UT, 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200228_0510_allsky_AJS_5396.jpg
A bright flare in Perseus caused by the satellite USA 238 and co-orbiting debris.

Alan. 20 Feb 2020, 21:33 - 21:35 UT, stack of two consecutive 58 s images. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200220_2135_allsky_composite_AJS_2857.jpg
An unidentified object leaves a trail of pink dots, the trail appearing broken because of the action of the LC light gate. Similar trails, although shorter, were captured on subsequent nights.

Alan. 17 Feb 2020, 05:54:29 - 05:55:27 UT, 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200217_055527_allsky_AJS_0619.jpg
A fireball in Cygnus, also imaged by Benelux observers, who estimated the trail at magnitude -1 and the terminal flare at magnitude -2.

Alan. 17 Feb 2020, 04:51:59 - 04:52:57 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200217_045257_fireball_AJS_0557.jpg
A spectacular fireball, also imaged by Benelux observers.

Alan. 16 Feb 2020, 21:51:39 - 21:52:37 UT, 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200216_215237_fireball_AJS_0140.jpg
A satellite manifests itself as a bright flare.

Alan. 11 Feb 2020, 04:51 - 04:52 UT, 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 6400, colour, LC light gate.

20200211_0452_allsky_AJS_0967.jpg
A satellite manifests itself as a bright dot in a single frame.

Alan. 11 Feb 2020, 02:57 - 02:58 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 6400, colour, LC light gate.

20200211_0258_allsky_AJS_0854.jpg
A faint meteor in Lepus. The object was also imaged by Benelux observers.

Alan. 06 Feb 2020, 19:22:59 - 19:23:57 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200206_192357_meteor_AJS_0099.jpg
06 Feb 2020. A fireball leaves a trail through Canes Venatici. The object was also imaged by Benelux observers. Cloud and lack of stars visible in the vicinity prevented a triangulation from being carried out.

Top: Alan. 01:47:11 - 01:48:09 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour. The trail appears segmented by the LCD light gate recently fitted to the camera.

Bottom: James. 01:47:33 - 01:48:03 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200206_014809_fireball_AJS_0195.jpg
20200206_014803_fireball_JMA.jpg
A faint meteor in Cygnus - just above the level of detection. The object was also imaged by Benelux observers.

Alan. 03 Feb 2020, 03:40 - 03:41 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 3200, colour, LC light gate.

20200203_0341_allsky_AJS_0639.jpg
The Japanese ALOS (Advanced Land Observing Satellite) creates a flare in Boötes. The flare would have been even more conspicuous were it not for glare from the Moon (phase 31%, waning) to the south.

James. 19 Jan 2020, 05:11:26 - 05:11:56 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200119_051156_allsky_JMA.jpg
18 Jan 2020. A meteor in Hydra.

Top: Alan. 23:31:19 - 23:32:17 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James. 23:32:05 - 23:32:35 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: estimates of the meteor track over the northern France. Yellow line: triangulation of James's and Alan's observations shows a descent from 96 km to the terminal flare at 54 km; blue line, corresponding estimate for Alan and one of the Benelux observers showing a notably different track. The baseline between James and Alan is really too short for successful triangulation, particularly in regard of objects directly to the east or west, so the blue estimate should be the more accurate of the two.

20200118_233217_fireball_AJS_7662.jpg
20200118_233235_fireball_JMA.jpg
20200118_233235_track.jpg
07 Jan 2020. A bright meteor streaks through Ursa Major and Canes Venatici.

Top: Alan. 06:16 - 06:17 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James. 06:16:44 - 06:17:14 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: triangulated path of the meteor over Suffolk, descending from an altitude of 78 km to 68 km.

20200107_0617_fireball_AJS_4391.jpg
20200107_061714_fireball_JMA.jpg
20200107_061714_track.jpg
04 Jan 2020. A second meteor of the night, this time in Coma Berenices and with sufficiently many stars visible to enable triangulation of the trajectory.

Top: Alan. 04:59:02 - 05:00:00 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James. 04:59:19 - 04:59:49 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: triangulated path of the meteor NE to SW off the coast of Essex, descending from 91 km to 79 km.

20200104_0459_fireball_AJS_3326.jpg
20200104_045949_fireball_JMA.jpg
20200104_045949_track.jpg
A fireball in Virgo, close to the first magnitude star Spica. Unfortunately, the area of the sky was behind considerable cloud. The meteor was also captured by Alan (behind cloud), by a member of the Benelux meteor group (no cloud) and by others. There were too few background stars visible through the cloud to enable triangulation.

James. 04 Jan 2020, 04:11:43 - 04:12:13 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200104_041213_fireball_JMA.jpg
Components of a bright "double dot" satellite in Hydra display contrasting blue and gold colours.

James. 01 Jan 2020, 06:41:44 - 06:42:14 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20200101_064214_allsky_JMA.jpg
A faint meteor in Corvus, only just visible above the background sky-glow. The object was also imaged by Benelux observers.

Alan. 23 Dec 2019, 05:22 - 05:23 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20191223_0508_fireball_AJS_8729.jpg
04 Dec 2019. A second meteor of the night, this time confirmed, leaves a short trail just west of Leo.

Top: Alan. 03:24:17 - 03:25:15 UT, single 58 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James. 03:24:51 - 03:25:21 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: triangulated path of the meteor over France and the North Sea showing a descent from 216 km to 60 km. The baseline between James and Alan is really too short for successful triangulation, particularly in regard of objects directly to the east or west, so the results should be regarded as broadly indicative. The estimated initial altitude is much higher than that at which a meteor would typically start ablating.

20191204_0325_fireball_AJS_2677.jpg
20191204_032521_fireball_JMA.jpg
20191204_032521_track.jpg
04 Dec 2019. A suspected meteor in Coma Berenices. Unfortunately, significant field distortions at the edges of the images prevented a triangulation from being carried out.

Top: Alan. 3:13:12 - 03:14:10 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Bottom: James. 03:13:12 - 03:13:42 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20191204_031410_fireball_AJS_2666.jpg
20191204_031342_fireball_JMA.jpg
A bright satellite flare in Hydra.

James. 03 Dec 2019, 05:54:26 - 05:55:57 UT, stack of three consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour. The imaging run overnight on 02-03 December 2019 was the first successful all-night run of the camera with software tailored to the task in hand (a full rewrite of Thomas Jacquin's excellent code used formerly).

20191203_055557_allsky_JMA.jpg
An Iridium flare in Cepheus.

Alan. 02 Dec 2019, 17:41 - 17:42 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20191202_1742_allsky_AJS_1346.jpg
A faint meteor in Virgo. The object was also imaged by Benelux observers.

Alan. 19 Nov 2019, 05:53:47 - 05:54:45 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20191119_0554_meteor_AJS_7569.jpg
It's unclear whether a bright trail near the northern horizon is caused by a meteor or a satellite.

Alan. 17 Nov 2019, circa 04:55 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20191117_0455_allsky_AJS_6608.jpg
A bright fireball in Perseus shows flares in its trail.

Alan. 07 Nov 2019, 03:53 - 03:54 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20191107_0354_fireball_AJS_4203.jpg
A bright satellite flare in Gemini.

James. 28 Oct 2019, 04:24:13 - 04:25:13 UT, stack of two consecutive 30 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20191028_042513_allsky_JMA.jpg
28 Oct 2019. The second fireball In the morning hours of 28 October crossed the boundary between Leo and Lynx and produced a terminal flare. The object was also imaged by Benelux observers who estimated the trail at magnitude -3 and the terminal flare at magnitude -6.

Top: Alan. 02:11:53 - 02:12:50 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James. 02:12:32 - 02:13:02 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: estimates of the meteor track over the North Sea. Yellow line: triangulation of James's and Alan's observations shows a descent from 113 km to the terminal flare at 87 km; blue line, corresponding estimate for Alan and one of the Benelux observers showing a descent from approximately the same starting point but on a different trajectory and with the terminal flare at 87 km. The baseline between James and Alan is really too short for successful triangulation, particularly in regard of objects directly to the east or west, so the blue estimate should be the more accurate of the two.

20191028_021250_fireball_AJS_0507.jpg
20191028_021301_fireball_JMA.jpg
20191028_021301_track.jpg
28 Oct 2019. A suspected fireball in Cetus shows brightness variations in its trail. Although imaged by both Alan and James, there were too few stars in the vicinity to enable a triangulation to be performed to estimate the altitude of the object.

Top: Alan. circa 00:44 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Bottom: James. 00:43:23 - 00:43:53 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20191028_0044_fireball_AJS_0419.jpg
20191028_004353_fireball_JMA.jpg
A satellite reveals its presence by a bright dot in Taurus.

James. 03 Oct 2019, 04:28:34 - 04:29:04 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20191003_042904_allsky_JMA.jpg
19 Sep 2019. A fireball crosses from Cassiopeia into Cepheus. Initially, the object was classified as a satellite; however, triangulation later showed it to be a fireball.

Top: Alan, 00:47 - 00:49 UT, single 81 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James, 00:48:46 - 00:48:56 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: triangulated path south to north over Suffolk and Norfolk, dropping from an initial altitude of 104 km to a final altitude of 92 km.

20190919_0049_fireball_AJS_1647.jpg
20190919_004846_fireball_JMA.jpg
20190919_004846_track.jpg
A satellite trail in Ursa Major shows a relatively uncommon double peak in brightness.

Alan. 18 Sep 2019, 03:54 - 03:56 UT, single 81 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190918_0356_allsky_AJS_1407.jpg
A satellite trail in Andromeda.

Alan. 05 Sep 2019, circa 03:16 UT, single 81 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190905_0316_allsky_AJS_9548.jpg
A fireball in Aquarius.

Alan. 04 Sep 2019, 20:07 - 20:09 UT, single 81 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190904_2009_fireball_AJS_9245.jpg
A streak with a bright flare through Aries. The trail has the brightness profile of a typical satellite flare, but the colour typical of a meteor, showing how difficult it can be to differentiate between the two. On balance, it's thought that the trail was created by a satellite.

James. 03 Sep 2019, 02:48:39 - 02:49:09 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20190903_024909_allsky_JMA.jpg
31 Aug 2019. A fireball in Lyra shows a bright terminal flare with some internal variation.

Top: Alan, 21:49 - 21:50 UT, single 81 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James, 21:49:46 - 21:50:16 UT, single 30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: triangulated path north to south over Suffolk, dropping from an initial altitude of 125 km to a final altitude of 79 km.

20190831_2150_fireball_AJS_8616.jpg 20190831_215016_allsky_JMA.jpg
20190831_215016_track.jpg
29 Aug 2019. A fireball in Ophiuchus with a modest terminal flare.

Top: Alan, 20:15:44 - 20:17:00 UT, single 76 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James, 20:15:39 - 20:16:09 UT, single30 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

Bottom: triangulated path north to south over Kent, dropping from an initial altitude of 84 km to a final altitude of 77 km.

20190829_201700_fireball_AJS_7841.jpg
20190829_201639_fireball_JMA.jpg
20190829_201639_track.jpg
A fireball in Camelopardalis.

Alan. 27 Aug 2019, 23:17 - 23:19 UT, single 76 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190827_2319_fireball_AJS_7622.jpg
A rotating satellite is manifest as two bright dots in Cygnus.

Alan. 26 Aug 2019, 23:24 - 23:25 UT, single 76 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190826_2325_allsky_AJS_7283.jpg
Two satellites. One, in Sagittarius (yellow circle), appears in only one frame. The other (red circle) travelled slowly through Cygnus in five consecutive frames.

Alan. 24 Aug 2019, 20:50 - 20:57 UT, stack of five consecutive 76 s exposures. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190824_2057_allsky_composite_AJS_6463.jpg
Twin surveillance satellites NOSS (Naval Ocean Surveillance System) 3-4 a and 3-4 c betray their presence by a double trail in Pisces. (See also image taken 15 May 2019.)

Top: Alan. 23 Aug 2019, 01:20 - 01:21 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Bottom: James. 01:20:21 - 01:21:21 UT, stack of three consecutive 20 s exposures. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20190823_0121_allsky_AJS_5973.jpg
20190823_012141_allsky_JMA.jpg
A helicopter creates a very distinctive trail!

James. 20 Aug 2019, 01:33:30 - 01:33:50 UT, single 20 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20190820_013350_helicopter_JMA.jpg
08-13 Aug 2019.
Observations of Perseid meteor shower 2019.
A fireball in Cassiopeia exhibits a bright terminal flare.

Alan. 25 Jul 2019, 00:02 - 00:03 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190725_0003_fireball_AJS_0499.jpg
A dual satellite streak in Capricornus. This was the first bright satellite captured by the ZWO camera. The image is compromised by glare from a bright Moon (phase 85%, waning).

James. 21 Jul 2019, 00:44:56 - 00:45:16 UT, single 20 s exposure. ZWO ASI 178MC with ZWO fisheye lens, f1.2, gain 200, colour.

20190721_014517_allsky_JMA_500.jpg
A fireball passing from Cygnus into Lacerta exhibits a bright terminal flare. The event was almost clouded out.

Alan. 18 Jul 2019, 23:58 - 23:59 UT, single 57 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f4, ISO 800, colour.

20190718_2359_fireball_AJS_8968.jpg
A constellation of SpaceX Starlink satellites is visible as a faint line of varying brightness.

Alan. 15 May 2019, 00:57 - 00:59 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190526_2310_starlink_AJS_5796.jpg
Twin surveillance satellites NOSS (Naval Ocean Surveillance System) 3-4 a and 3-4 c betray their presence by a double trail. (See also image taken 23 Aug 2019.)

Alan. 15 May 2019, 00:57 - 00:59 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190515_0059_allsky_AJS_5276.jpg
A passage of the International Space Station (ISS), with a much fainter accompanying trail created by a Russian SL-4 rocket body. The magnitudes are respectively -4.0 and +1.9.

Top: Alan. 14 May 2019, 01:09:24 - 01:11:25 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Bottom: James. 01:08:50 - 01:09:51 UT, stack of six consecutive 10 s exposures. RPi and PiCamera v2, ISO 800, monochrome.

20190514_0101125_allsky_AJS_5122.jpg
20190514_010850_allsky_JMA.jpg
A streak with a bright flare through Virgo could be caused by a satellite or a meteor, but on balance probably the former. (Yellow circle.) Jupiter is indicated by the red circle at 5 o'clock and Saturn by the red circle at 6 o'clock.

Alan. 26 Apr 2019, 02:55 - 02:57 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190426_0257_fireball_AJS_3897.jpg
A satellite crossing Ursa Major creates a short trail with a central bright flare.

James. 21 Apr 2019, 21:03:00 - 21:03:10 UT, single 10 s exposure. RPi and PiCamera v2, ISO 800, monochrome.

20190421_210301_allsky_JMA.jpg
A suspected meteor in Gemini exhibits a long trail with several flares.

Alan. 20 Apr 2019, 21:45 - 21:47 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f4.0, ISO 800, colour. (The lens was stopped-down slightly compared to its usual setting because of the bright moonlight.)

20190420_2147_allsky_AJS_3109.jpg
A bright fireball appears behind trees on the horizon. The object was also imaged by members of UKMON, NEMETODE and the BAA. Triangulation of images by UKMON placed the object above Lincolnshire, UK.

Alan. 30 Mar 2019, 03:51 - 03:53 UT, single 150 s exposure. Canon 1100d with 4.5 mm Sigma fisheye lens f2.8, ISO 800, colour.

20190330_0353_fireball_AJS_9910.jpg
A satellite on the boundary of Ursa Major and Leo Minor creates a trail of short streaks of light. The trail is visible on three consecutive nights and shifts slightly against the background stars.

Top: James. 29 Mar 2019, 00:40:01 - 00:41:02 UT, stack of six consecutive 10 s exposures. RPi and PiCamera v2. ISO 800, monochrome.

Alan. 4.5 mm Sigma fisheye lens, 150 s exposures, f2.8, ISO 800, colour. Images on three consecutive nights as follows:

20190329_004001_allsky_JMA.jpg
20190329-31_satellite_dots_AJS.png
A satellite appearing to consist of three distinct objects is manifest in a single frame.

James. 28 Mar 2019, 21:47:18 - 21:47:28 UT, single 10 s exposure.

20190328_214719_allsky_JMA.jpg
A dual trail created by military satellite USA 238 and associated orbital debris.

Alan. 25 Mar 2019, 20:14 - 20:16 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens f2.8, ISO 800, colour.

20190325_2016_allsky_AJS_9132.jpg
A bright satellite flare in Boötes. Comparing images by Alan and James (inset), the flare shows negligible parallax relative to the nearby triangle of stars formed by θ, 17 and 21 Boötes, indicating that the object which created it is at a distance of at least several hundred kilometres and is therefore a satellite rather than a meteor.

James. 18 Mar 2019, 03:13:48 - 03:14:09 UT, stack of two consecutive 10 s exposures. RPi and PiCamera v2, ISO 800, monochrome. Inset: James LHS, Alan RHS.

20190318_031348_allsky_JMA.jpg
An extended satellite flare passes through Corona Borealis and Boötes, with a bright peak luminosity.

James. 25 Feb 2019, 04:59:53 - 05:01:25 UT, stack of nine consecutive 10 s exposures. RPi and PiCamera v2, ISO 800, monochrome.

20190226_050115_allsky_composite_JMA.jpg
A fireball in Hydra is visible near the horizon. The object was also imaged by Benelux observers, enabling triangulation of its trajectory.

Alan. 15 Feb 2019, 20:09 - 20:11 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190215_2011_fireball_AJS_3683.jpg
A fireball in Lepus is only just visible behind thick cloud. The object was initially missed on examination of the photos and was spotted on a more thorough examination following a report by a visual observer. A 60% waxing Moon creates a bright background sky.

Alan. 13 Feb 2019, 20:55 - 20:57 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190213_2057_fireball_AJS_3151.jpg
A fireball in Leo shows a bright terminal flare.

Alan. 31 Jan 2019, 03:02 - 03:04 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20190131_0304_fireball_AJS_1490.jpg
A double trail reveals a likely spy satellite (at the top of the frame), unlisted in readily available resources. Comet 46P/Wirtanen is also circled, left of centre. Montage showing the motion of 46P/Wirtanen, 09-13 December 2018.

Alan. 24 Dec 2018, 17:37 - 17:40 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens f2.8, ISO 800, colour. The image was captured approximately 10 minutes after the image immediately below.

20181224_1740_allsky_AJS_7138.jpg
Two frames show a flare caused by surveillance satellite NOSS3-3A (one of the US Naval Ocean Surveillance Satellites). The flare commenced towards the end of the first frame (bottom) and brightened during the second (top). The images were captured before the Moon, at 93% phase waning, caused severe brightening of the sky.

Alan. 24 Dec 2018. Bottom: 17:21 - 17:24 UT, top: 17:24 - 17:27 UT. Both frames are 150 s exposures. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20181224_1727_allsky_AJS_7132-3.jpg
A fireball in Ursa Major with a terminal flare.

Top: Alan. 10 Dec 2018, 05:38 - 05:40 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

Middle: James, 05:38:40 - 05:38:50 UT, single 10 s exposure, ISO 800, monochrome. RPi and PiCamera v2, background stars labelled.

Bottom: triangulated path west to east over Essex, dropping from an initial height of 111 km with the terminal flare just south of Sudbury at an altitude of 84 km.

20181210_0538_fireball_AJS_5920.jpg
20181210_053841_fireball_annotated_JMA.jpg
20181210_053841_track.jpg
A satellite flare in Lacerta.

James. 17 Nov 2018, 19:04:00 - 19:04:10 UT, single 10 s exposure. RPi and PiCamera v2, ISO 800, monochrome.

20181117_190401_allsky_JMA.jpg
A passage of the International Space Station ISS from west to east (right to left), emerging from Auriga and passing through Lynx and Ursa Major.

James. 04 Nov 2018, 05:20:46 - 05:21:47 UT, stack of six consecutive 10 s exposures. RPi and PiCamera v2, ISO 800, monochrome.

20181104_052147_ISS_JMA.jpg
The track of a satellite spans the height of the frame, from Cepheus (top) through Cygnus (bottom).

James. 03 Nov 2018, 18:41:03 - 18:43:06 UT, stack of twelve consecutive 10 s exposures. RPi and PiCamera v2, ISO 800, monochrome.

20181103_184103_allsky_JMA.jpg
A passage of the International Space Station (ISS).

Alan. 03 Nov 2018, 04:36 - 04:39 UT, single 150 s exposure. Canon 1100D with 4.5 mm Sigma fisheye lens, f2.8, ISO 800, colour.

20181103_0436_ISS_AJS_1400.jpg
Two streaks in an image (top) were initially thought to be meteor trails. The brighter streak (red circle) was imaged by both Alan and James; rescaling and overlaying the two images (bottom) shows the brighter trail, from James's camera, overlaid over the fainter, from Alan's, with no significant parallax, indicating that the object responsible is at least several hundred kilometres distant, too far for a meteor. (Although alignment between the two images is good within the vicinity of the trail, is not good over the images as a whole, because of the different field distortions suffered by the two imaging systems.)

James. 10 Oct 2018, 03:03:38 - 03:03:48 UT, single 10 s exposure. RPi and PiCamera v2, ISO 800, monochrome.

20181010_021830_allsky_annotated_JMA.jpg
20181010_030339_sat_trail_overlay_JMA_AJS_8171.jpg
Almost one week after first light, the camera recorded a bright satellite dot, in one frame, equidistant from Capella and Algol.

James. 10 Oct 2018, 02:18:29 - 02:18:39 UT, single 10 s exposure. RPi and PiCamera v2, ISO 800, monochrome.

20181010_021830_allsky_annotated_JMA.jpg
A fireball exhibits two terminal flares.

Alan. 08 Oct 2018, 20:10 - 20:12 UT, single 150 s exposure. Canon 1100D with 10-18 mm Canon zoom lens set to 10 mm, f4.5, ISO 800, colour.

20181008_2012_fireball_AJS_7750.jpg
First light of the camera. The image is unremarkable!

James. 04 Oct 2018, 19:21:04 - 19:21:14 UT, single 10 s exposure. RPi and PiCamera v2, ISO 800, monochrome.

20181004_192105_allsky_JMA.jpg
The bright track of the ISS is accompanied by the faint track of supply vessel Kounotori HTV7, manoeuvring to dock with it. (The track of the companion is faintly visible in the image to the right at maximum resolution.)

Alan. 26 Sep 2018, 19:48 - 19:50 UT, single 150 s exposure. Canon 1100D with 10-18 mm Canon zoom lens set to 10 mm, f4.5, ISO 800, colour.

20180926_1950_ISS_AJS_6022.jpg
The trail left by military reconnaissance satellite USA 186, Keyhole/Crystal KH-11. The craft allegedly carries an optical telescope in excess of 2.5 m aperture, theoretically able to image objects as small as 5 cm on the surface of the Earth! Above and to the left, there are two aircraft trails (appearing as lines of well-spaced dashes).

Alan. 26 Sep 2018, 19:33 - 19:35 UT, single 150 s exposure. Canon 1100D with 10-18 mm Canon zoom lens set to 10 mm, f4.5, ISO 800, colour.

20180926_1935_allsky_AJS_6016.jpg
A pair of trails, obviously closely linked, reveals a double-satellite. The object is designated USA 229, but was originally a member of the NOSS series. One of the pair is classed as debris, and moves a short distance behind the other.

Alan. 24 Sep 2018, 20:02 - 20:05 UT, single 150 s exposure. Canon 1100D with 10-18 mm Canon zoom lens set to 10 mm, f4.5, ISO 800, colour.

20180924_2005_USA229_AJS_5537.jpg
First light of the camera with the 10 mm Canon lens. The additional sensitivity of the new lens is obvious, with the Milky Way and the Andromeda galaxy clearly visible.

Alan. 06 Sep 2018, time not recorded. Single exposure. Canon 1100D with 10-18 mm Canon zoom lens set to 10 mm, 150 s exposure, f4.5, ISO 1600, colour.

20180906_allsky_AJS_3466.jpg
Close to the constellation Hercules, four dots of light (one relatively bright and three fainter, in line) betray the presence of the French military surveillance satellite Helios 1A. It has been monitored at magnitude -4 on one occasion by keen observers! A full moon illuminates the entire sky and terrestrial objects.

Alan. 25 Aug 2018, 22:03 - 22:06 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, colour.

20180825_2206_Helios1a_AJS_2598.jpg
The first Iridium flare captured by the camera. The flare was caused by Iridium 54, and appears between Deneb and Vega, on the right of the image. Heavens-Above.com gives the time of the flare as 02:17:28 UT.

Alan. 15 Aug 2018, 02:13 - 02:18 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, colour.

20180815_0218_Iridium54_AJS_1800.jpg
Sky vista looking due east. A satellite flare, initially mistaken for a meteor, is visible in Pegasus.

James. 10 Aug 2018, 23:15 UT, single 8 s exposure. Canon 6D MkII, 24-105 mm lens at 24 mm, f3.5, ISO 4000, colour.

20180810_231434_Per+Cas_JMA_5180.jpg
Sky vista looking due east. A satellite flare is visible in Cepheus (yellow circle), one aircraft trail in Perseus, close to the Double Cluster (red circle) and another in Pegasus. The yellow arrow highlights the Andromeda Galaxy, M31.

James. 10 Aug 2018, 22:52 UT, single 8 s exposure. Canon 6D MkII, 24-105 mm lens at 24 mm, f3.5, ISO 4000, colour.

20180810_225138_Per+Cas_JMA_5094.jpg
The night of 11-12 August was the only one offering clear skies around the time of the Perseid meteor maximum in 2018. The sky was very transparent following two days of heavy rain which had washed the atmosphere clear of dust and the Moon was new on 11 August, so did not interfere with observations. Although the camera did not record any meteors, it did catch several satellite trails, of which the brightest, in Draco, is to the right.

Alan. 11 Aug 2018, 00:04 - 00:09 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, colour.

20180811_0009_allsky_AJS_1595.jpg
The first fireball recorded by the camera! It exhibits a train, two intermediate flares and a terminal flare. The Moon has risen and, although out of frame, has caused internal reflections. Focus is not perfect.

Alan. 06 Aug 2018, 00:07 - 00:12 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, colour.

20180806_0012_allsky_AJS_1369.jpg
A short satellite trail in Lyra, below right of centre of image.

Alan. 03 Aug 2018, 22:48 - 22:54 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, colour. This is the first colour image with the camera. It was taken through thin cloud.

20180803_2254_allsky_AJS_1180.jpg
A passage of the International Space Station (ISS), at maximum magnitude -4.0. The Milky way is also clearly visible.

Alan. 20 Jul 2018, 00:14-00:19 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, monochrome.

20180720_0019_allsky_AJS_9968.jpg
A brief flare created by US NOSS (Naval Ocean Surveillance Satellites) 3a and 3c. (The two satellites are tethered together in orbit.)

Alan. 19 Jul 2018, 23:08 - 23:13 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 1600, monochrome.

20180719_2313_allsky_AJS_9955
Time-exposure photographs often capture streaks or trails caused by satellites. The image shows a faint satellite trail above centre.

Alan. 05 Jul 2018, 23:07 - 23:12 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, exposure, f11, ISO 1600, monochrome.

20180705_2312_allsky_AJS_9300.jpg
Sky vista looking due south. Five satellite trails are visible! (Some are very faint.)

James. 03 Jul 2018, 21:14 UT, single 5 s exposure. Canon 6D MkII, 24-105 mm lens at 24 mm, f3.5, ISO 4000, colour.

20180703_211414_satellite_trails_JMA_2219.png
First light from the all-sky camera. The image was indistinct and showed little detail; in part this was because the sky was cloudy, in part due to lack of familiarity with the equipment. Improvements in image quality soon followed.

Alan. 16 Jun 2018, approx 22:30 UT, single 300 s exposure. Canon 1100D with adapter-Helios-Spiratone lens combination, f11, ISO 800, monochrome.

20180616_2230_allsky_AJS_8061.jpg

Alan's Cameras

Alan's first all-sky camera was a second-hand Canon 1100D, used with the following lenses:

The camera was originally mounted in a home-made wooden box which, for use, slotted into a mounting on the roof of a garden shed. The box was fitted with a 1.5 W dew heater resistor and a convex clock-glass to protect the lens. An intervalometer was used to take exposures of specified duration. Several improvements were made subsequently:

20180728_170517_fireball_cam_AJS.jpg The components inside the camera box, with the adapter-Helios-Spiratone lens combination.

20180728_170454_fireball_cam_AJS.jpg The box with the clock-glass cover shut, ready for use.

20200510_gibbet_AJS.jpg The gibbet with the box mounted on top.


The camera sensor is more electronically noisy than would be ideal, and this results in numerous visible "sparkles" when images are examined at full resolution. Fortunately, the "sparkles" may be easily distinguished from background stars as they appear as points of light, whereas the stars exhibit trails due to the length of exposures used.

In March 2021, Alan invested in a new camera, a ZWO ASI294MC. Unfortunately, when used with the Sigma 4.5 mm lens and LC shutter used previously with the 1100D, images were compromised by pronounced Moire patterns. After considerable experimentation, he developed a rotating mechanical shutter, which worked satisfactorily with the camera and lens.

Martin's Camera

See the description in the June 2021 Newsletter, pp. 22-25.

James's Camera

James progressed through several iterations of imaging equipment as follows.

Version 1

The first version of equipment, in use 10 June - 10 August 2018, comprised a Canon 6D MkII camera with 24-105 mm lens set to 24 mm. The camera was mounted on a fixed tripod and, by using short exposure times, generally 5 s or 8 s, star trailing was negligible. The camera took images every few seconds. The aim was simply to explore what could be seen in wide-field views of the sky throughout the night.

The camera recorded many satellites and countless aircraft trails. An image of 5 s duration, captured on the evening of 24 July 2018 (see above), showed five satellite trails! A later image, of 8 s duration, taken on 10 August 2018 (see above), showed typical trails from both types of craft. Aircraft trails are easily recognised by the characteristic patterns of their navigation lights. However, initially, Alan and James could not reliably distinguish between meteor trails and satellite flares. Eventually, once they had gained experience in differentiating between the two, it became clear that the camera had, unfortunately, during its period of operation, recorded no meteors at all. The camera produced some interesting images but was too fragile and expensive to leave outside, unattended, all night.

Version 2

The second version of equipment comprised a Raspberry Pi (RPi) single board computer (SBC) and PiCamera v2. This provided a serviceable albeit limited capability and, being relatively low cost, could be left out all night without worry! The RPi was mounted in a weatherproof ABS enclosure; the PiCamera protruded through a hole in the enclosure and was protected from the elements by a clear acrylic dome. The RPi was connected to the home network via an Ethernet cable (wi-fi proved unreliable). Four resistors, in two pairs positioned diametrically opposite inside the dome, delivered up to 6 W of heat to keep the dome free of dew. (Software control enabled adjustment of the power fed to the resistors.) At 62.2°x48.8°, the FoV was far less than "all sky", nevertheless, it proved sufficient to obtain some interesting results. The camera had a fixed focal ratio of f2.0, and was used with both exposure and ISO settings at maximum, respectively 10 s and ISO 800, which enabled detection of stars down to approximately magnitude 7.8 overhead, under ideal conditions. Although the PiCamera was set to record contiguous back-to-back images, in practice, processing times resulted in a short inter-image delay, causing visible gaps in some satellite trails. In use, the camera was positioned in the garden resting on a table, pointing vertically upwards, which resulted in images centred on the zenith. The images below show the inside of the enclosure and the equipment ready for use, awaiting nightfall. "First light" was on 04 October 2018.

In part due to the small FoV of the PiCamera, it was some two months before it recorded its first meteor, in a frame terminating at 05:38:41 UT on 10 December 2018. Alan also captured the meteor in an image and it was therefore possible to triangulate the trajectory, which was found to be approximately west to east over Essex (see track above). The methodology used for triangulation was that of [1] as implemented in [2] (with some modifications).

Version 3

The small field of view of the PiCamera proved frustrating, and the third iteration of equipment was aimed at obtaining images of higher quality and with a wider field of view. To that end, the camera was upgraded to a ZWO ASI178MC with ZWO fisheye lens (2.5 mm, 1:1.2), operating under control of an RPi. In order to minimise the size of the enclosure housing the camera, a small acrylic dome was used. The dew heater system was similar to that of version 2, and utilised four resistors mounted inside the dome. However, because of the small size of the dome, they had to be mounted together, rather than being spread around the circumference. The equipment was initially operated under the INDI (Instrument Neutral Distributed Interface) software suite [3]. Although INDI's camera control capabilities proved satisfactory, the software enabled production of images only in FITS (Flexible Image Transport System) format, and provided no support to convert files to alternative formats for post-processing. Frustration with the FITS format led to the replacement of INDI with software by Thomas Jacquin [4]. In use, the ASI178MC camera was positioned outside a window in the roof of the house, providing a good southern horizon but a severely restricted northern view (due to the roof itself). Surprisingly, positioning the camera in this way was repeatable. First light of the ASI178MC camera with Thomas Jacquin's software was on 12 July 2019.

Version 4

The ZWO camera and fisheye lens imaged several bright meteors and generally performed satisfactorily. However, the lens was of low quality, and suffered from considerable distortion at the edges of the FoV which made it difficult to triangulate the paths of some meteors. As a fourth iteraton of equipment, the lens was replaced with a Fujinon fish-eye lens, model CF2.7HA-L1, 1:1.8, 2.7 mm (obtained pre-owned from ENS Optical). The 4th iteration came into use on 28 July 2020.

On decommissioning version 3, it became apparent that mounting the dew heater resistors close together had been a mistake. The circulation of warm air inside the dome appeared to be limited, and it had been necessary in winter to run the resistors at a total power of 3.0 W to ensure that the entire dome was sufficiently heated to prevent dew from forming; at this power, the resistors were too hot to touch, and in fact had caused charring of the ABS in the vicinity. Fortunately, the Fujinon lens introduced in version 4 was considerably larger than its predecessor, necessitating a larger acrylic dome (10 cm diameter versus 8.5 cm) and a new, larger enclosure. The larger dome enabled the fitting of eight dew heater resistors equally spaced around the circumference, providing an even distribution of heat. Even though the volume of air inside the dome of version 4 was considerably larger than that of version 3, because of the greater number of resistors and the more even distribution of heat, each resistor could be run at lower power, in use never more than warm to the touch, with no danger of causing charring of the enclosure.

At first in version 3, Thomas Jacquin's software was used unmodified, as downloaded from github. However, throughout the use of versions 3 and 4, it was gradually tailored and optimised to support James's pattern of use of the camera. Ultimately, the software was completely re-factored.

20181103_PiCamera_enclosure_JMA_9444.jpg The inside of the enclosure showing the PI, PiCamera, power supply and associated components.

20190421_PiCamera_ready_for_use_JMA_5569.jpg The PiCamera ready for use, awaiting nightfall.

20190811_ASI178MC_ready_for_use_JMA_0796.jpg The ZWO camera ready for use, awaiting nightfall.

20200709_Fujinon+heaters_JMA_0991.jpg The Fujinon lens and dewheaters.

Meteors and Satellites

There are many satellites in orbit, and they appear as points of light or trails in time-exposure photographs. The most prominent satellite is the ISS, which can create a trail as bright as magnitude -6.0 extending over much of an arc of the sky. Initially, Alan and James found it difficult to reliably identify trails in images as satellites or meteors and, indeed, identified many satellites erroneously as meteors. Fortunately, with practice, their powers of discrimination improved!

In general, satellite trails are symmetric, smooth and of a single hue (reflected sunlight), whereas meteor trails are generally asymmetric (often with a terminal flare event), sometimes show internal structure and can exhibit varying colours as different gasses are ablated by the passage of the meteoritic body through the Earth's atmosphere. A meteor moves much faster through the sky than does a satellite so, in trails of comparable length, when an LC is used, the trail created by the satellite will contain many more segments than that created by the meteor.

References

[1]

Zdenek Ceplecha, "Geometric, Dynamic, Orbital And Photometric Data On Meteoroids From Photographic Fireball Networks", Bull. Astron. Inst. Czechosl. 38 (1987), 222-234.

[2]

Denis Vida, 2016, Python programme for meteor triangulation, https://github.com/CroatianMeteorNetwork/CMN-codes/blob/master/triangulation/MeteorTriangulation.py.

[3]

Open Astronomy Instrumentation, "Discover INDI", www.indilib.org/about/discover-indi.html.

[4]

Thomas Jacquin, "A Raspberry Pi operated wireless allsky camera", github.com/thomasjacquin/allsky.git.


Alan Smith, Martin Richmond-Hardy, James Appleton