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Who says images of small satellites in the outer solar system can't be artistic? This one was taken with my 0.4m Dilworth telescope. A Dilworth uses several relay lenses in the optical train, each of which scatters a very tiny amount of light. Usually the scattered light is completely undetectable but if a very bright object, Saturn in this case, is just outside the field of view effects like this can be produced when contrast is enhanced. Saturn was about a million times brighter than its satellite Phoebe, which is marked with the cross lines. Phoebe was magnitude 16.6 at the time of observation, 2021-07-08.

Now that JWST is up and on its way to its L2 orbital position, the upper stage of the Ariane launcher that put it there is in a (highly perturbed) solar orbit. We know it will return to the vicinity of the Earth around 2047 but not precisely where and when. Recovering it will be quite tricky without a good prediction from an accurate orbit. This is where amateur astronomers can play a big role. All we have to do is image the launcher for as long as possible and measure its position against the background stars as precisely as possible. It is also moving, so you need to record the timing of the images to within a second or so. Finally, because it is so close to the Earth there will be a significant parallax effect so you need to report your geographical position too. The object is currently around 16th magnitude. It should remain visible until some time in February, though that depends on scope aperture, sky conditions, exposure length and so on. Bill Gray at http://projectpluto.com is coordinating the results. I can likely help out by answering questions you may have. Paul

It's difficult to get a sense of scale in this astronomy game; but we try. So here are 8 pics of the ISS passing between Vega and Epsilon Lyra last night - which is a second's worth of my Canon 7D firing off as fast as it can. The background is a single 30 second tracked exposure for a bit of context. Details: Esprit 100 prime focus/Canon 7D:1/1000s ISO1600 +30s background. The trick if you want to try this is to use planetarium software to find out exactly when the ISS will be near a bright object, then pre-align and focus on or near that object, then wait for the ISS to appear in the finder before letting the shutter go in rapid mode. I also optimised pre-focus on the computer using the focus feature on Nebulosity before switching the camera back to stand alone mode.

Dear SGL. Your opinion is required please. We are very lucky and live in Southern Central France with stunning dark skies. When we get time we look up at the wonders of the night sky. Last night we set up our sunbeds and after a bit of bat watching we settled back to a couple of bottles of red and some cheese. We saw a few shooting stars the milky way as bright as ever, 2 iridium flares as predicted by ISS tracker and lots of air traffic. But we saw those strange flashes again! On several occasions in the past my GF has spotted very brief flashing lights, sometimes 2 in the same place. I poo pooed her until I saw them to. Then I was the one who was poo pooed! Sometimes these flashes are in different parts of the sky but we have confirmed today they all lie at around the same angle and mainly in the eastern to southeastern sky. We do not currently have a great view south so have not noticed them there. So a more detailed description of these flashes: They are brief - less than half a sec. Bright - brighter than any star in the vicinity. They do not seem to be associated with and moving object - satellite/plane. They are sporadic - sometimes you will see 2 or 3 in an evening, sometimes 1. Sometimes you will see 2 flashes in exactly the same spot seconds or a few mins apart. From reading the forums here I get the impression we are witnessing Geostationary satellite Flares but I can't be sure? How often do those distant objects use their thrusters? How bright is hydrazine? Should we be able to see them? As all the sightings tend to be in the same area it sort of points to that but I really don't know. Your opinion is greatly appreciated.

Hi all, My friend and I were outside last night looking at the sky and looking for satellites. We saw a few of what I assume were satellites (flat unblinking steadily moving lights) One of them which crossed the sky East to West emitted 2 incredibly bright and intense, very large flashes of pure white light, spaced maybe 2 minutes apart from each other. Neither of us have any more than a basic school knowledge of astronomy but are both interested. We wondered if anyone on here could help shed any light on the flashing satellite we saw? Many thanks for your time. Iain

Hi all. I was out most of last night under a lovely clear sky and did a spot of basic imaging of a few Messiers. On looking at the images today there were plenty of satellite trails as always, and Stellarium helps me identify them mostly, but I'm having trouble identifying one, so any help or useful sources I can try would be appreciated. The area I was looking at was around M90 and in taking 20 or so one minute exposures I spotted a couple of trails. The first moving slowly took around 10 minutes to cross the width of the imaged area so appears on ten images and I can't find a match for this. The image below was taken at approx. 2.14am. The second trail moves fairly swiftly taking about 1.5 minutes to travel the length of the frame, so moving much faster and appears to be Cosmos 2476, taken at 2.23am. Any ideas welcome. I've assumed its a satellite and not an asteroid or another one of those Teslas

At long last I have managed to image Caliban, also known as Uranus XVI. It is a small (circa 72km) outer satellite of Uranus which was discovered in September 1997 using the Hale 5m telescope at Palomar. Incidentally, Sycorax (U-XVII)was discovered in the same observing session. That satellite is around 1.7 magnitude brighter and so much easier to observe. Although a three hours exposure, unfiltered for maximum sensitivity, was used the signal to noise ratio is barely 3 and serious image processing was needed to produce a relatively clear image. Even so, it is not especially obvious. The reason is that the MPOC ephemeris predicts that the satellite has a magnitude of 22.2 at the time of observation. More information is available at http://www.astropalma.com/Projects/Satellites/caliban.html

History changed on October 4, 1957, when the Soviet Union successfully launched Sputnik I. The world's first artificial satellite was about the size of a beach ball (58 cm.or 22.8 inches in diameter), weighed only 83.6 kg. or 183.9 pounds, and took about 98 minutes to orbit the Earth on its elliptical path. That launch ushered in new political, military, technological, and scientific developments. While the Sputnik launch was a single event, it marked the start of the space age and the U.S.-U.S.S.R space race. http://history.nasa.gov/sputnik/ Probably a malicious apocryphal rumor, but I once heard the Russians programmed Sputnik to transmit a radio signal which was used by many automatic door openers. Supposedly gates and garage doors were opening and shutting like crazy all over the USA as the satellite passed overhead. Great sense of humor IF it's true!

49 images and 20 darks taken on an eq6 mounted 5D MKII and 24mm lens, 15 second exposures @ f4 iso800. A quick and dirty process through DSS and CS5, next time I'll push it to iso1600 to get more data in the images. I'm not sure due South looking at the Milky way is the best view to get the meteors because of the satellite traffic in the region, it's like the Olympic traffic lane in rush hour.

I have written a blog post about imaging artificial satellites, with a focus on the ISS. Since the SGL challenge is precisely about that, it thought it could be interesting to share. The article is there: https://satelliteobservation.wordpress.com/2017/04/20/observing-satellites/ It has a bit of background in the beginning on satellites and how imaging a satellite is similar to a satellite imaging the ground, plus some discussion about the different types of mount and tracking and of what limits imaging performance. The conclusion is that a dob + a high-speed, high resolution camera is a good way to go to make images like these: There are some very nice images from other people in there too.

Hi all, Was taking some white light sunspot snaps with my SCT and DSLR and spotted an object moving fast across it. Had a look at CalSky.com but couldn't find anything obvious (though I'm not sure I'm using the site right). Anyone got any idea what this might be? Satellite or...other? Cheers Jim

The Galileo system of navigational satellites will be a European equivalent of the US GPS or Russian GLONASS navigation systems. Here's a brief notice from ESA: http://www.esa.int/Our_Activities/Navigation/Galileo/Launching_Galileo/Watch_the_launch_of_Galileo-13_14 Europe takes its next step in creating its own navigation satellite constellation on Tuesday 24 May, with the launch of the 13th and 14th Galileo satellites. The pair is scheduled to lift off at 08:48:43 GMT (05:48:43 local time, 10:48:43 CEST) on 24 May from Europe’s Spaceport in French Guiana atop a Soyuz launcher. The first three stages of the Soyuz rocket take the Galileo satellites and their Fregat upper stage into low orbit just short of nine minutes after liftoff. Then the reignitable Fregat, as much a spacecraft as a rocket stage, then takes over the task of hauling the satellites higher through a pair of burns. The satellites will be released in opposite directions by their dispenser once they reach their target 22 522 km-altitude orbit at 3 h 48 min after launch. Streaming begins at 08:28 GMT (10:28 CEST) on 24 May for the liftoff, then resumes at 12:23 GMT (14:23 CEST) to cover the satellites’ separation.