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I didn’t expect to see anything from Chelmsford but I set up a video camera with a 200mm lens looking at the horizon in the expected azimuth. Nothing detected.
Yes, a real shame that the second stage failed well short of orbital velocity.
Grant/Paul,
Yes, ignore my comment about it being 500 km up over LP. I forgot that the altitudes in the flight profile plot are kft. 500 kft = 152 km so at SECO it is indeed around 160 km up.
Damned imperial/metric confusion again.
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The ground track from the Virgin site shows the launcher crossing La Palma at around T+ 560s. The vehicle is in the Earth’s shadow but the second stage motor will still be burning at that point (SECO is around T+ 590s). It will be over 500km up when it crosses over LP. It might be visible coming up in your north but I have no idea how bright the exhaust plume would be at that range and you have a bright Moon to contend with as well.
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Yes, the spaceports in the Highlands and islands will be for vertical launches unlike the air launch approach adopted by Virgin Orbit. They are all currently aiming for 300 kg or so to polar LEO. You can do a lot with that mass these days. They are also looking at being able to insert small payloads into heliocentric orbit so missions to the Moon and other planets are possible with these small launchers. You only need really big stuff for people!
For the UK vertical launch vehicles have a look at Skyrora and Orbex:
https://www.skyrora.com/
https://orbex.space/Skyrora in particular are using a very British set of propellants (Hydrogen Peroxide and RP-1 kerosene). These were used in the Black Arrow launch of Prospero 50 years ago.
It is not just careers and training, it is a potentially huge and very lucrative business.
Regarding range safety the mission planning ensures that there is a very low probability of debris hitting anyone. The CAA wouldn’t licensed the launches otherwise.
The attached plot should allow you to determine the visibility at your location. Use the ground track and launch profile plots to determine the altitude and great circle distance from your observing site and the curves show how far above the horizon the launcher will be. For example if it is 1000 km away and 150 km in altitude it will be around 4 degrees above your horizon.
First stage burnout (MECO) is at around 180s and occurs at an altitude of around 75km. For the far southwest tip of Cornwall the ground track shows a great circle distance of around 450km. This corresponds to an elevation of around 10 deg above the horizon so the first stage should be visible from Cornwall if the weather cooperates. The visibility from SW Ireland is similar.
If anyone gets any video or images please send them to me. I can include them in the Sky Notes at the next meeting.
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There is lots of useful technical information in the VO Service Guide here:
https://virginorbit.com/wp-content/uploads/2020/09/LauncherOne-Service-Guide-August-2020.pdf
On page 22 there is a launch profile diagram showing altitude (in 1000 ft) vs time. We also have the visibility maps here:
https://virginorbit.com/the-latest/where-can-i-spot-the-launcherone-rocket-on-launch-day/
I am assuming these mean that the vehicle is above the horizon from a particular location so they are very optimistic in terms of visibility. For example at 300s after drop the second stage will be burning and the altitude will be around 500,000 ft or 150km. At 300s according to the launch track it will be around 1000km great circle distance from Salisbury (off the northwest coast of Spain) so a bit of trigonometry gives a height above your horizon of 4 degrees I think.
You might want to check that maths. It is a bit early in the morning…
I still don’t have mine in Chelmsford but the mail is pretty terrible at the moment and I’ll give it another couple of weeks before I request a replacement.
Ta David. I’ll keep this one on file. Good to see the quality press providing a worthy entry in a category normally dominated by the tabloids. No giraffe-based dimensions though.
Here’s a grotty image of the field from last night (Dec 15). It was quite hazy and my sky is very bright at the moment due to the blanket of now on the ground.
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Aladin shows a faint galaxy at this position and the NASA/IPAC database lists two sources associated with it. The WISE source that Paul identified and a GALEXASC source (GALEXASC J062056.21+781041.4). Do you know when the background image in your message was taken?
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Jack, thanks for the pictures and David, thanks for the details. There are a few “Astronomer” pubs around the country. I wonder how many have rooms like this?
Yes, very enjoyable and great to see so many people at the meeting. Does anyone have any info on that Wray refractor at the pub?
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.
