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Saw multiple Starlink satellites this evening from 20:00 to 20:30 UT including 7 at the same time, all at about mag 1.
Just read the next batch are due to be launched tomorrow, Wednesday, April 22 at 3:37 p.m. EDT [1937 GMT] – see https://www.space.com/spacex-earlier-starlink-6-launch-date-april-2020.html
Hi Peter,
As far as I am aware the PST ‘rust’ problem only occurs on the main objective lens and not elsewhere. Since you mention that your objective is ‘blue’ then this would indicate you do not have the rust problem. Even with low activity in hydrogen alpha, such as at the moment, you will always be able to see the chromospheric network that occurs all over the disk – see for example the second image (right hand side) on page http://www.petermeadows.com/astroimaging/ (this Ha image was taken with a PST).
You should slowly adjust the etalon ring and always ensure you have good focus until you see the network. You may need to move the etalon back and forth and few times. If the solar disk is uniform without any texture than you are either off frequency or there is a problem with the etalon.
With your PST did you every see any prominences/filaments etc? Is it still under warranty?
Hope this helps.
Peter
Hi Peter,
I saw both planets this evening as well at about 17:30 UT. First spotted Mercury in binoculars low down in the west and once found it was easily seen with the naked eye.
Peter
I thought I recognised the comet photo in the Mirror article – it is Comet West 1975 VI from 1976 – see the following link
https://enacademic.com/pictures/enwiki/67/C_1975_V1_%28West%29_1976-03-09_6h_UTC.jpg
I was new to astronomy back then but heard about this comet but failed to see it in the pre-dawn sky – I then joined ‘The Astronomer’ to make sure I didn’t miss any other bright comets!
According to N2YO.com (https://www.n2yo.com/passes/?s=74001) there are three good passes over southern UK overnight such as the following from Chelmsford (note times are BST):
The most detailed information I’ve found on this constellation can be found at https://space.skyrocket.de/doc_sdat/starlink-v0-9.htm.
Peter
Hi Lars,
The Minor Planet Center will be able to provide an Ephemeris via web page https://minorplanetcenter.net/iau/MPEph/MPEph.html. You will need to use C/1980 Y2 for the comet name and then add the date you want such as the discovery date of 19801225 and then an ephemeris will be created such as that below for a geocentric observer. You can change the observer location by adding an Observatory Code (e.g. 000 for Greenwich which will be sufficient for the UK).
Hi JR,
Firstly I assume you have successfully using the PST visually with an eyepiece to see the chromosphere – although solar activity has reduced recently there is a reasonable group at the moment which even produced a flare this afternoon. So if all is OK using the PST visually this indicates that you have correctly wavelength tuned the telescope. If it off-band you will just see a featureless disk a bit like in your image.
The difficult part of using a DSLR or indeed any other type of camera with a PST is obtaining focus. This requires using a Barlow lens (which you appear to be using) or an eyepiece lens to bring the focal plane of the DSLR closer to the PST eyepiece holder. I suggest you perform a Google search using ‘PST and DSLR’ without the quotes. There you will find videos and other information (e.g. https://www.youtube.com/watch?v=RYDzdYkVbGM). Note there is no need to modify the PST eyepiece holder itself.
Peter
Hi Denis,
If you go to the ‘About Us’ tab on the BAA home page and then select ‘Who’s who’ you will find a list of trustees, the council and section directors. As I was at the AGM last October, the number of votes for each candidate for the current council was given – I assume this part of the meeting has been included in the video of the meeting (but I’ve not checked myself’.
Best wishes,
Peter
Hi David,
I suggest just emailing the excel file to Lyn. She will extract your observations and use them for the monthly solar section newsletter.
Peter
Hi David,
The blue cells in the Solar Section white light reporting form are for the total number of groups (gn, gs, g), sunspots (fn, fs, f) or sunspot number R seen during a month. Gn, Gs and G are the number of active area/groups seen in the northern hemisphere, southern hemisphere and the whole solar disk on each observing day respectively. If you only count the number of groups for the whole disk, then please leave the gn, gs, fn, fs columns blank. R is 10*g + f.
The MDF values are the mean daily frequency values for gn, gs, g – i.e. these are the average number of groups during the month. Finally R in cell J43 is the average R value for the month.
Once you have completed your form, please send to Lyn Smith (solar@britastro.org).
Peter
The attached image shows NGC 6946 acquired on 2017 May 14 at 11:07 UT using iTelescope T24 in California (the average of 3 x 120s exposures) and a comparison DSS image (using Aladin v9.0). The cross and red circle shows the new object (not visible in the DSS image). A larger version of the image is attached.
Astrometrica gives a magnitude of V=13.1 and position RA 20 34 44.24, Dec +60 11 36.1 (J2000) for the new object.
