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Why have such a low limit? Maybe increase it to 10 to be sure. If we start getting spam posts from members then we can handle that at the time.
On the old site the latest forum posts were on the front page but this is not currently the case with the new site. That is a shame since the forum is the most interactive part of the site. I know that you can get to the forum via the community tab but many people and casual visitors will not bother to do that. Can we get the latest forum posts back on the front page please?
My astrometry gave 16.1 last night for JWST. It varies a lot. It is still moving north and it reaches max declination north (about +19 deg) about mid March. It will cross the equator in the middle of April and then head south for a while. I haven’t tried for the booster since Feb 10 when it was around mag 20.3.
That is a very unusual mount but clearly very effective since he discovered 10 comets from 1873 through to 1912:
19P/Borrelly, C/1873 Q1 (Borrelly), C/1874 O1 (Borrelly), C/1874 X1 (Borrelly), C/1877 C1 (Borrelly), C/1889 X1 (Borrelly), C/1900 O1 (Borrelly-Brooks), C/1903 M1 (Borrelly), C/1909 L1 (Borrelly-Daniel), C/1912 V1 (Borrelly)
I assume that they were all with this instrument but I haven’t checked.
This is such a shock. I met Rob quite a few times in the 90’s. He was a great observer and did a lot for the Lunar Section at that time. Rob observed quite a few comets too and we have some examples of his notebooks in the Comet Section archives:
https://britastro.org/cometobs/1969y1/1969y1_19700331_0345_rmoseley.html
https://britastro.org/cometobs/1987p1/1987p1_19871028_rmoseley.html
https://britastro.org/cometobs/1988a1/1988a1_19880510_rmoseley.htmlIf you haven’t seen it yet there is an amazing “selfie” of JWST’s primary mirror on the JWST blog taken using the pupil imaging lens in NIRCam.
Isn’t the web wonderful? I like this statement at the top of that page: “Once the book has been published (anticipated publication date May 2005), the download option will be disabled, so authors should take advantage of the opportunity to download their chapters now”.
That’s a very interesting observation.
There is an entire chapter on this in Comets II (edited by Festou, Keller and Weaver) which describes the generation and distribution of species in the coma (pp 425 onwards). It was published in 2004 before much of the recent space-based observations of comets but it is an excellent reference book if you can get hold of a copy. I can see some second-hand around £60 online. The book is so massive that it is in imminent danger of collapsing under its own gravity. A more recent book, “An introduction to comets” by Nicolas Thomas is post-Rosetta and also covers this.
I run my RMS cameras at 1920×1080, the normal configuration is 1280×720. This increases the file size a bit. I also use ffmpeg at a higher quality level.
This one is drifting slowly in alt/az downwards and to the right. It is NORAD 21893 (Superbird B1) which was launched in 1992 and which is long defunct. It is in a highly inclined (14 deg) graveyard orbit. Uncontrolled GEOs are perturbed by lunar and solar gravity and their inclination drifts away from 0 deg.
It is almost stationary in alt/az so must be near GEO. Candidates are Eutelsat W2, Telstar 6 and Meteosat 8. All three are drifting slowly slightly above GEO in the graveyard.
As of Feb 3 the telescope is pointing at HD 84406 in UMa. This should mean that we can calculate the aspect angle of the sunshield and the effect this has on the apparent magnitude as seen from the Earth. It might explain why the telescope was so much brighter last night. The optical collimation has now begun and the blog has a fascinating description of how it will be done. It is well worth a read.
JWST has been mag 13.0 from around Feb 4.85 to Feb 5.01 tonight, pretty bright for an object at L2. The Ariane upper stage, which is now 2.5 million km away, was around 20.2 at Feb 4.95.
That is an impressive mangling of two perfectly good facts (you can image the spacecraft with a telescope from Earth and the first calibration star is a binocular object in UMa) to produce a typically silly Daily Mail science story. Thanks both for giving me a chuckle over breakfast.
John – That is a really useful document and it would be great to get it uploaded as an HTML page somewhere that is easy to find on the website. Hopefully you can get the circulars uploaded too. Once they get indexed they will be easy to search and that would be a great resource. I know that a new website design is on the way and it would be nice to see a dedicated BAA archives section on that.
I’ve been gradually scanning Comet Section material and some of that is here.
It was cloudy here in Chelmsford but I was a long way to the east of the track in any case. The 55km eastward shift is almost at the prediction’s 3-sigma error so that seems quite significant.
Sheridan, I wonder where these other items, particularly the circulars, ended up. They would certainly be very useful if they were online and searchable. Do you still have copies?
I’m not aware of one but it would certainly be nice to have. My first paper circular is No. 557, dated 1974 October 16. It announced the discovery of Nova Sgr which became V3888 Sgr I think. They were a slightly odd paper size (not quite A5) in those days but would probably be something that could be scanned quite quickly.
I’ll be talking about JWST at the meeting tomorrow. If you have any recent observations please let me know by tonight. I got some astrometry of the Ariane upper stage a couple of nights ago and it is now around magnitude 19. The observatory was mag 16. Everything seems to be going very well with the mission so far.
