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See John Rogers’ post for context:
https://britastro.org/section_news_item/juice-heading-for-jupiter-this-week
Note that today’s launch has just been scrubbed due to the risk of lightning at Korou. The spacecraft requires an instantaneous launch window but this repeats around a minute earlier each day. The ephemeris on JPL Horizons will probably be updated with the new target launch time but, if not, the track should be pretty similar each day with the time shifted slightly.
Separation of the Juice spacecraft from its launch vehicle was confirmed a few minutes ago. Its on the way!
Something to look forward to imaging – if it clears tonight.
Grant – Good luck with imaging JUICE tonight. A typically excellent Ariane 5 launch. Acquisition of Signal at the ESA Deep Space Antenna at New Norcia was a bit of a nail-biter but in the end everything was fine. It just took a while for JUICE to settle itself down and enable its transmitter.
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Fantastic to know that JUICE is on its way safely, even though it will require four flybys of Earth or Venus before it really heads for Jupiter!
Cloudy on Friday night but marginally better on Saturday. Magnitude: 15.
Would have been a very easy object under good sky conditions.JPL Horizons: 2023-Apr-15 22:05 12 08 17.94 -03 53 10.9
AstroArt: JUICE C2023 04 15.92043 12 08 17.81 -03 53 05.1 15.0 VAttachments:
Nice one!
here it was cloudy one night, then I had an equipment failure the next… Might have another clear night in time for the first flyby. 🙂
Nick – Well done getting it. It was reported as mag 13 on the first night so in line with my original predictions. You might want to have a go for the Ariane upper stage too. You can get ephems from https://projectpluto.com/sat_eph.htm.
Currently looking at the location suggested by JPL Horizons and am really surprised by how bright this thing is for something man made half a million miles away.
And thats under murky conditions. Image at https://britastro.org/observations/observation.php?id=20230418_002705_da18d9fe717fc9b0
Nice one, Grant!
Better skies here on April 17th, but not as good as your ‘murky conditions’. I reckon around mag. 17 as predicted by Project Pluto but we both have the booster as much fainter whereas Project Pluto had it 0.1 mag brighter.
Image: https://britastro.org/observations/observation.php?id=20230418_144755_2de4bfdcf6b88a29
Were it not for an Avast antivirus software update knackering – in a very subtle manner – the ability of the observatory PC to talk to the house, I would have been imaging at the same time as you – before the mist started rolling in about 12:30. Looking at my post meridian flip image sequence, the stars are gradually fading as the transparency went to pot.
Will measure some brightness values later…
Grant – You really do seem to have an extraordinarily unreliable system. If it was me I would have taken a sledgehammer to it by now.
I can’t imagine what you mean. 🙂
I never quite established what it was the Avast had done, but it lost contact the moment it started its update. Took me 2 evenings to coax it back to life – worked fine via keyboard, but refused to talk over Wifi. Fine now…
I think its fortunate that I attended a failing North London comprehensive in the 1970s. It equipped me with the robust language skills I needed to properly describe exactly what I thought about the staff at Avast, the authors of Windows 10 and life, the universe and everything.
Lets just say …. I was somewhat vexed.
Here is an image from 18/04/2023 at 21:00 UTC with the spacecraft now at 1.1 million km range. I took 40 frames with 30 second exposures at f6.3 on an 250mm SCT. I estimate the brightness of JUICE as about 16.0 based on the field stars. Starlink 1956 passed through the frame at 21:04 UTC and appears in 2 of the stacked frames.
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just did a quick unfiltered imaging estimate of the magnitude of JUICE around midnight 17/18th April and get 16.3 with a fairly steady value and a position that agrees with JPL Horizon at the <1 arc sec level.
Will try again tonight…
JUICE was SNR=15 in 30s exposures this evening – must get the OAG going again.
Have never really checked. Managed 20.4 with the 10″. Got a Z=5 QSO but the unfiltered mag of that was uncertain as a lot of the light was shifted into the red – am guessing mag 20.8. Suspect that on a good clear night with a high target and no Moon I am looking at 21. Would need to be an interesting target. 🙂
Just processed my results from last night. JUICE was at mag 17.3 using an unfiltered Trius 694 and Gaia g comparisons.
Just about able to still image JUICE now over 1 million miles distant. I had to track the motion of the spacecraft as it was too faint for imaging at sidereal rate. Project Pluto gave a magnitude of 18.6 but I think it was a bit brighter, maybe closer to 18.
https://britastro.org/observations/observation.php?id=20230422_170616_b8fadbebb39febdd
I am imaging JUICE at the moment and after stacking 5x 60s frames (aligned on the star field) I could see a hint of the track. As its a hazy night, that sounds like the bright end of 18th mag. Will do some proper sums tomorrow and post the picture.
Tonight it is 1.4 million miles away.
Time to break out Tycho tracker I think. Will be interested to see how far we can push things.
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