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Composites should always be marked as such so that it is clear that parts of the image have been processed separately and then recombined. People can then make a judgement about how “real” the image is. I wouldn’t say that a composite is a “fake” since, if done properly, it shows what would have been seen if the limitations of the telescope and camera had not been present. A good example is stacking a moving object, such as a comet, separately from the fixed stars. I agree though that this is open to abuse from people who are less than honest about how the image has been generated.
And 3rd and 4th contact were 05:59:02 and 05:59:31 although the seeing by then was even worse.
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I got a good (electronic) view here in Chelmsford too. I’ve uploaded a full frame image of the Moon and Mars and a frame from the video:
https://nickdjames.com/20221208_Mars_occultation/moon_20221208_0456_ndj.jpg
https://britastro.org/observations/observation.php?id=20221208_051712_492f9d9303a0d800From my video I get first contact at 04:59:56 and 2nd at 05:00:29. The seeing was pretty poor though. Temperature at the moment is -2.8C.
Here we go again. Another attempt to launch SLS and Artemis-1. The launch window opens at 0604 UTC tomorrow (November 16) and if it goes at the start of the window we may get to see it on the first morning although the sky will probably be too light. After that, things are not so good. You can get an ephemeris from JPL Horizons if you want to have a go at observing it on the way to the Moon. There is an opportunity over the next few mornings as the spacecraft moves through Virgo, Libra and Scorpius.
That is really sad news. I met Bob at the TA AGM in 2006 September. At that meeting we had Tom Boles, Mark Armstrong, Maurice Gavin and Ron Arbour, all of whom had discovered supernovae using imaging. By that time Bob had discovered around 40 supernovae, all visually. Bob’s talk was excellent and should be around on video somewhere. I do remember him passing on greetings to those of us who lived “in the northern polar regions”. I don’t think he fancied observing from here!
Fascinating.
Following Alex’s link gets to a rather complicated map but, if I understand it correctly, the whole event is only visible during totality from Indochina. I’ve just checked using Stellarium and, indeed, they have a good view of this from Hanoi. The next time this happens is 2235 so I guess we are quite lucky!
I wonder if we will see any pictures of it.
Nick.
You don’t need to wait for a fast moving NEO to pass by. I regularly check my timing accuracy by doing astrometry of GPS satellites as explained by Bill Gray here:
I’ve put a speeded up version of my eclipse video here:
https://www.nickdjames.com/Eclipses/20221025/eclipse_20221025_ndj.mp4
The entire eclipse in 35 seconds.
Someone on Youtube yesterday said that watching a partial eclipse was like watching paint dry. As a public service this video is short enough that it should not stress the attention span of most social media users.
Clear here at the moment and the livestream is running. Under 30 mins to go.
https://www.youtube.com/watch?v=1nUMDx8PiF4
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My livestream on Tuesday morning will be here:
The forecast for Tuesday here is light cloud all morning so it may not be a very interesting livestream! At least it is not likely to be raining…
Much better conditions tonight but the spacecraft is now around mag 19.
https://britastro.org/observations/observation.php?id=20221018_013758_7e01f580c6581403A few tiny gaps between the rain clouds in Chelmsford. The fact that it is very close to the Moon doesn’t help but it is around 16.5 at the moment on the one out-of-focus image that I’ve managed to get.
Here’s the badly out of focus image:
https://britastro.org/observations/observation.php?id=20221017_033930_ce425b3fe9fb12a2I got the spacecraft and Centaur upper stage a day after launch in 2021 October and so will certainly be having a go for this flyby. Closest Earth approach is 11:02 UTC on 2022 October 16 when it should be visible with the naked eye from Australia. Our best opportunity is the morning of October 17 when it will be in Gemini. It was mag 17 when I imaged it on the way out in 2021 and the SWRI web page below suggests it will be 12-16 the day after flyby then fading at around 2 mags/day.
https://britastro.org/observations/observation.php?id=20211017_203152_36007e488544b44e
http://lucy.swri.edu/SpotTheSpacecraft-EGA1.htmlIt is interesting that the velocity change is larger than would be expected and it appears that much of the momentum change came from ejecta rather than the spacecraft. That is something specific to rubble-pile objects I guess. A solid object would produce far less ejecta.
That was fun to watch last night and the last image few images showed a huge amount of detail on Dimorphos. It looks like quite a few people, including some using small telescopes, detected the impact flash and subsequent dust cloud. I’m quite surprised how prominent the impact was from Earth although a quick calculation shows that the spacecraft kinetic energy was around 12GJ, so approx. the equivalent of 3t of TNT.
Hi David,
I had a great view of that comet and NLC too on the night of Friday/Saturday, 2020 July 10/11. That night was one of the best observing experiences of my life. A stunning naked-eye comet and really dynamic and bright NLC.
Sadly we don’t have anything like that at the moment. The brightest comet around in the northern sky is probably C/2022 E3 (ZTF). It is around 13th mag at the moment so probably too faint for a small telescope but we hope that it will reach 6th magnitude in late January next year when it will be moving rapidly across the sky under the pole.
The best places to go to get an idea of the current state of comets in the sky is Jonathan Shanklin’s site here:
https://people.ast.cam.ac.uk/~jds/
and our Comet Section image archive here:
https://britastro.org/cometobs/
For the latest images of C/2022 E3 scroll down to near the bottom of the list and then click on the “gallery” link.
We’re always happy to receive observations of comets so please let me know how you get on.
Thanks for posting the videos. It was a great meeting, very enjoyable and well attended. My thanks to everyone involved, particularly Hazel, the Sigma crew and Lorna and Helen at UHIM.
After giving my talk on monitoring the sky with video cameras I headed north to install one of these low-cost cameras at Denis Buczynski’s observatory at Portmahomack. This has a fantastic northern horizon and the camera is intended to capture NLC and aurora. A couple of live clips from last night show a very nice, active aurora with the foreground illuminated by moonlight:
http://nickdjames.com/TarbatnessN/TarbatnessN_20220914_2153.mp4
http://nickdjames.com/TarbatnessN/TarbatnessN_20220914_2322.mp4A still made from stacking 128 video frames is attached. It shows how well these little cameras work.
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This document has some useful background information on SLS. In particular it has a timeline including the ICPS disposal burn on page 55:
https://www.nasa.gov/sites/default/files/atoms/files/sls_reference_guide_2022_print_0.pdf
Nick.
An updated ephemeris for the rescheduled Artemis launch time (window opens on Sept 3 at 18:17 UTC) is on JPL Horizons. This has much better visibility for us on the evening of the launch. The spacecraft rises around 20:00 UTC and gets above 40 deg altitude by 21:00. The upper stage separation burn is at T + 2hr 7min so may well be visible from the UK if the sky is clear.
Let’s hope that they now fully understand the LH2 bleed and the RS-25 cryogenic conditioning problems that scrubbed the last launch and that the weather cooperates on both sides of the Atlantic.
Ted Molczan has provided a table of expected magnitudes for the spacecraft (Orion) and the SLS upper stage and spacecraft adaptor (the Interim Cryogenic Propulsion Stage) on seesat:
http://satobs.org/seesat/Aug-2022/0236.html
They indicate that Orion will be 13th mag on the night of launch fading to 17th mag at lunar distances with the ICPS around 1 mag fainter.
The ICPS will be deflected from the spacecraft trajectory by a disposal burn shortly after trans-lunar injection (TLI). This will target a lunar flyby which will put the stage into a heliocentric orbit. The stage will probably do a propellant dump shortly after the disposal burn as part of its passivation procedure. Sadly we are not going to see that from here but it could be an interesting sight for people in the right place. Have a look at Chris Taylor’s description of the equivalent from the Apollo 8 S-IV-B upper stage:
https://www.hanwellobservatory.org.uk/news/apollo-8-from-the-other-side-of-the-pond
JPL Horizons has an ephemeris for Orion but not the ICPS. It is likely that an ICPS ephemeris will appear here:
https://projectpluto.com/sat_eph.htm
Good hunting. Please post any images you get on this website.
