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Nice stamps. That plural is certainly correct in the original latin (where they had strict rules about such things) but I doubt if many Engish speakers would use it now. Reminds me of the Romanes eunt domus skit in the Life of Brian…
That would be a sad end for IRAS (famous for the discovery of C/1983 H1 Iras-Araki-Alcock). The predicted time of close approach is 23:39:35 UTC tonight according to LeoLabs.
Gary, yes the sound levels were a bit low although fine if you have a big volume knob on your amplifier it seemed OK. It partly depended on the speaker’s voice and where they were standing. I’ve just had a look at the recordings (which are now on the meetings page BTW) and I can turn it up far enough. I’ll discuss with the IoP whether we can push it up next time.
Andrew. Many thanks for that observation. This is a good opportunity for visual views as well as imaging.
It’s now close enough that I can fit it in the field of my wide-angle imaging system. This is an image from Chelmsford tonight.
This is an update of the plot I posted last year. It is the count of meteors from my two cameras since this is the only objective measurement of sky conditions that I have. The sporadic count is probably the one to use since it is not dependent on conditions at the times of shower maxima. This shows a slight deterioration on 2018 and my lowest detection rate so far. Note that 2015 was only a partial year (from June) but most meteor activity is in the last half of the year so it is not easy to scale.
David,
I think these are definitely Burnham. Stefan Beck has suggested dates and times. I’ve updated the page with the latest info although I may have missed some. Independent confirmation would be good.
Nick.
Lars/Paul, That’s a great start with the plate solving. Now we just need to know which comets passed through those points to get the observation date and time. More difficult will be identifying the observers!
I too am surprised that astrometry.net is so good with trailed stars/
You’re right, but two mags is quite a lot. I doubt if it would be anywhere near that and would only apply to satellites under control since it is on only one face. Since quite a few are tumbling already it may not be very effective. From our point of view I think we will become more dependent on large numbers of short exposures and clever stacking software. CMOS cameras have come along at just the right time.
Thanks for the feedback. I’ll speak with the AV people at the IoP and will try to improve this for future meetings.
A recording of the entire event is online at the original URL given at the top of this thread. You can scroll through to find the best bits.
Thanks all for the feedback. I think it mostly worked well. With the support of the IoP we hope to be able to do this for all our London meetings from now on.
Before 2I all of the comets that we know with very slightly hyperbolic orbits acquired the extra velocity through planetary perturbations when they were in the inner Solar System. We would expect comets falling in from the Oort cloud to be in parabolic orbits, i.e. have a velocity of zero at infinity. The largest eccentricity known prior to 2I was 1.057 for C/1980 E1 (Bowell). This large excess velocity (around 3.8 km/s) was acquired from a Jupiter encounter in 1980 December. Comet C/1956 R1 (Arend-Roland) had an exit eccentricity of 1.0002. The pre-perihelion eccentricity was indistinguishable from parabolic. The ultimate end for our comets is to either fall into the Sun or be ejected from our Solar System and become an interstellar comet for some one else.
At least when Peter Dunsby discovered Mars (AT 11448 here) he was presented with a nice certificate.
As you say, that’s minor planets. Perhaps we should send them a link to Dominic’s site: https://in-the-sky.org/data/planets.php
Seriously, if an amateur did this they would be crucified although at least we are trusted to post discoveries on TNS. We are not allowed to post to The Astronomer’s Telegram since we can’t be trusted to get things right on our own. I’d be interested to know what checking the MASTER team do before posting their discoveries. Checking for moving objects like asteroids and planets is pretty basic stuff. It would be nice to see a comment on TNS from one of the authors explaining what went wrong but so far nothing.
