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There is an early spectrum from the 2SPOT team from their robotic ALPY 600 setup in Chile
which seems to be evolving fast compared with the description of one taken less than 12 hours later referenced in Atel 15420
In times of crisis, I find myself turning to Prof Ned Wright’s tutorials. These FAQ are useful here
What is the redshift ? https://www.astro.ucla.edu/~wright/cosmology_faq.html#z
Can objects move away from us faster than the speed of light? https://www.astro.ucla.edu/~wright/cosmology_faq.html#FTL
Are galaxies really moving away from us or is space just expanding? https://www.astro.ucla.edu/~wright/cosmology_faq.html#MX
Actually the formal definition of redshift z (eg as quoted for a particular object in the literature) does not involve velocity at all. It is determined by direct measurement z = (measured wavelength/rest wavelength)-1. It is when this is interpreted as a velocity without considering relativity, the frame of reference and the particular cosmological model that the problems occur9 May 2022 at 2:47 pm in reply to: imminent merger of supermassive black hole binary ? #610134
I don’t know know of any formal campaigns involving amateurs though the AAVSO did contact the author offering support and there are a number of observers contributing brightness measurements. Here is the thread on the AAVSO forum
I took a couple more spectra and contacted the author who though they might be showing some changes and would follow it up with some measurements of their own, though I have not heard anything since. A quick look at the AAVSO light curve does not show anything obvious.
Also if I click on the post number next to my post
it takes me to the top of the next page instead of to the post. It should point to
Have the attachments been stripped from pre uplift posts ? eg
Is there any news on this? Are the stripped attachments recoverable or have they been lost ?
Based on the notes in the WDS it is considered an optical pair which I take to mean it is not a binary but just two stars “passing in the night”
EDIT: it appears the link has broken somewhere. I’ll leave you to navigate to it via WDS
According to the Washington Double Star Catalogue
the separation was 2.1 arcsec in 1871 and 4.2 in 2019. This reference has it as 3.9 arcsec in 2002
so also consistent with it widening currently.
Visual doubles is not my field but I guess 4 arcsec separation with a 5 magnitude difference in brightness could be pretty tough
Are the scanned versions of the JBAA supplied to ADS by the BAA or do they generate them? I noticed that vol.128, no.3, p.187 seems to be missing there. Instead there are two copies of p 185 and some wrong numbering in this series
Impressive (I had used my own name, not expecting it to crop up in so many editions !)
Now that the Journal articles are catalogued in ADS and are open access there, does it still make sense to limit access to historic editions of the Journal via the website to members only ?
Looks to be working ok here now.
How does the “Search” feature on https://britastro.org/journal-page work ? I tried entering something in the box, it whirred for a bit and then just appeared to reloaded the same page.
How do I amend one of my forum posts? I see some contributors have managed it but how to do it eludes me.
Any guidance gratefully accepted.
I have found this hit and miss. I wonder if editing is only allowed within a short time period or only before a reply has been added, systems which I have seen on other forums. Some forums eg Stargazers Lounge also mark posts as edited and have a place to comment the reason for the edit which is useful
Robin4 April 2022 at 10:56 pm in reply to: Journal of Occultation Astronomy paper on use of Flash Spectrum Video #609558
That’s an impressive amount of information they were able to extract from the video. I recorded a flash spectrum video using a webcam during the 2006 eclipse and was happy to get anything, even if, as it turned out, it was poorly focussed
I am preparing a detailed rebuttal but that is not top of my ToDo List currently – watch this space!
Its OK the deadline is not until 1st April 2023
The NASA page on the JWST sun shield mentions a “pink” colour due to the coatings
This is consistent with the reflectance spectrum and is similar to the pink colour seen reflected from the new Baader Bessel filters which use dielectric coatings to reflect all wavelengths except the green V passband, in place of the traditional coloured glass. Here is my new Baader filter on the left alongside my traditional coloured glass V filter.
- This reply was modified 3 months, 1 week ago by Robin Leadbeater.
The correct link to the observation page
(Tried to edit the post but can’t find an edit option)
Best highlight that one to Callum and the webops team, just checked my email notification and it indicates the BAA? very odd.
I’ve removed the post as it appears to contain personal information of a BAA member
It Looks like there are loads of bugs in this function. I have just gone back to read your message and it has disappeared! Also when I selected the message I sent to you I got directed to this site.
This is the email notification I got with the failed link
You have received a new message in
British Astronomical Association
From: Daryl Dobbs
Subject: private messages
Please Click the following link to view full Message.