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David. Yes the ion tail is very active again. Your images are excellent. Your fast RASA is ideal for this.
Gideon van Buitenen has produced a really nice simulation of the comet’s appearance which you can find here:
http://astro.vanbuitenen.nl/resources/C2022E3_simulation.gif
It shows the PA of the ion tail swinging around very rapidly over the next few days.
Interesting. I let my iTel subscription lapse since their kit was unreliable and the cameras were mostly old and/or not well calibrated. If things improve I might be tempted back. I did try Skygems but many of their instruments are offline or broken at the moment. Does anyone have any suggestions for good, reliable, high-quality remote observing. I would prefer pay-as-you-go since I don’t use it that often.
A very nice event. I got it on two cameras from Chelmsford:
https://britastro.org/observations/observation.php?id=20230111_000436_356d03a9d87988cd
There is a video from a fireball camera in Lanzarote which shows a bright and slow fireball northwest of the Canaries at 23:18:50.
https://twitter.com/RedSpmn/status/1612727698048311297
Drop time was 23:09 so this is around 600s downrange. Virgin Orbit stated that the vehicle reached 4.9 km/s which is a long way short of orbital velocity but fast enough to ablate on re-entry so this is consistent with re-entry of the second stage and payload.
If anyone else has contacts in the Canaries please ask if they saw anything.
As Grant says, putting stuff in orbit is still hard. Falcon 9 makes it look easy but Space-X has had a lot of practice.
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?
