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Glad you got to see it, Jeremy!
The brightness of this one was much closer to the prediction, so glad about that. Despite the moon, I managed to spot it as it came out of some cloud about a minute before the flare, which surprised me. My guess about the previous flare is that the prediction may have been based on slightly out of date orbital information. For objects in low earth orbit, this information changes often (depending on the orbit, anything from a few hours to a few days) due to interactions with the edge of the atmosphere and small gravitational perturbations.
The next bright evening flare is on the evening of May 17 and the moon won't be up. The current prediction has it about ten times brighter than tonight's one.
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We appreciate the updates Tom. It is something of a wonder to consider that tiny speck of hardware speeding along at 17Kmph. Surreal. And, Orbital Mechanics - ouch ! Wayyy beyond my modest math skills.
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Thank you, Jeremy. So few people get to see a truly dark sky and we are blessed with being able to do that in Puna. Whether you understand orbital mechanics or not doesn't matter, but if you pass on these observations of the night sky to your children or grandkids, you might possibly be influencing the next Einstein. Even if that's unlikely, you might pique their interest in science, math, and engineering and help make their (and our) future promising. It's how I started (thanks to my father).
Tom
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Just in case anyone is interested, Jupiter is very close to the moon right now and will get as close as a degree away. Unfortunately, its closest approach in the sky will happen around midday on Sunday our time, but anyone looking at the sky just before sunrise or after sunset Sunday evening will see both close to each other. It's already quite a nice sight tonight.
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If the weather improves (it's forecast to), there's a very bright Iridium flare predicted for the evening of Wednesday 17th May at 20:20:24. Again, Jupiter will help find the position before the flare.
If you locate Jupiter (fairly high up if you look in the south) and then look eastwards, you'll see a bright star. This is Arcturus (Hokule'a in Hawaiian). The satellite will pass just east of Arcturus before the flare which will occur to the east of Jupiter.
It's predicted magnitude is -7.6 which is roughly 130 times brighter than Jupiter, so ought to be very bright!
Sky track:
https://goo.gl/OxgFlx
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TomK, thanks so much. Will mark the calendar. Let's hope for clear skies.
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Wednesday 17th May at 20:20:24. Again, Jupiter will help find the position before the flare.
It's predicted magnitude is -7.6 which is roughly 130 times brighter than Jupiter, so ought to be very bright!
Looking forward to seeing this Iridium flare!
It... lends weight to Goethe's felicitous description of architecture as 'frozen music.' ... Does this, I often wonder, make music 'defrosted architecture?' Listening to Bach's Goldberg variations as I often do on walks when motorway noise and other auditory intrusions preclude the music of silence, it strikes me that it might. - Pub Walks in Underhill Country, Nat Segnit
"I'm at that stage in life where I stay out of discussions. Even if you say 1+1=5, you're right - have fun." - Keanu Reeves
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What timing - the sky between Jupiter and Arcturus cleared perfectly moments before the flare. We were able to find the satellite before it flared and follow it along. So bright !
A few seconds later, there was a 2nd, not-as-bright object on a similar trajectory. We tracked it as it brightened and dimmed, but it was nowhere near as bright as the Iridium. No idea what it was.
3 for 3 so far ! Thanks again TomK.
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Yes, that was a bright one! I also saw the object following it which did a mini-flare. I can't be certain, but just looked things up and think it was a large piece of debris from a Pegasus rocket -
https://en.wikipedia.org/wiki/Pegasus_rocket - although can't rule out something else like a military satellite which may not have publicly available orbital information. I've never seen something like that before!
Edited: Fixed the link.
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OK, just double checked. The 2nd object was actually another Iridium satellite. I didn't even think of checking because they are spaced out in a way that they wouldn't be so close to each other, so was surprised to learn what it really was.
There was a piece of debris from a Pegasus rocket very nearby, but in the end, probably too faint to see.
