Search Results for 'Join'

[Daryl Dobbs]

One way to go about it is to find a comfortable position to sit or stand and measure your eyelevel from the ground. Subtract from this the height of the mount from where it would join the pier to the position of the eyepiece when your telescope is at the lowest practical observing position and also when the telescope is at it’s highest practical observing position. That should give you an idea of the pier height. depending on your interests and location you might find there’s a certain ‘band’ of altitude your favorite objects reside in I’m thinking of planets or the Moon which will make choosing the pier height a bit easier.

Another method may seem a bit odd. But if you get a pole higher than the top of the sides of your observatory you wedge it in the vertical position. This simulates the pier. Next take another pole which will simulate the telescope and tie it with string to what you think is a suitable height to the vertical pole. You then can pivot the pole simulating the telescope up and down to find out if the observing height is practical. If not just untie the ‘telescope pole’ and move it up or down the vertical pole until you are happy with the range of heights from the viewing end where an eyepiece would be. Measure on the vertical pole the point where the ‘telescope pole’ is to the ground and subtract from this the height of the mount and you will arrive at your desired pier height.

If you change your telescope you might have to put an extension piece on top of the pier or use steps. 

I hope this helps

[Neil Morrison]

I have a book  Lessons in Astronomy by  Norman Lockyer first printed in 1868. My edition  is the  revision  of April 1889.

There are two plates in it   Page115 paragraph 256   “”Let us  begin with Mars .. We give in Plate IX  two sketches taken in the year 1862. ,Here at once we see that we have something singularly  like Earth. The  shaded  portions  represent water , the  lighter ones land , and the bright spot at the top of the drawings is probably snow lying  round the  south po0le of the planet  which was then visible. The upper  drawing was made on the 25th september ,the lower one on the 23rd In the upper one a sea is seen  on the left , stretching  down northwards ; while , joined on  to it  as the Mediterranean is joined on to the Aatlantic, is a long  narrow  sea , which  widens at its termination.  Paragraph  259 Mars not only  has land and water and  snow ‘but it has  clouds and mists, and these have been watched  at different times.  The land is  generally  reddish  when the planets atmosphere is clear ; this is due to the  absorption  of the atmosphere, as is the  colour of the setting  sun with us.  The water  appears of a  greenish tinge.     

Paragraph 259a   A  very  curious  feature  of the surface of Mars was detected  in 1877, when the planet made  one of its nearest approaches to Earth.  the so called “continents” were then seen to be  divided into innumerable  islands  by a network of ” canals”, or long and narrow  arms of the seas, some times running  almost in a straight line for 3,000 or 4,000 miles.  It was on the same occasion that the moons of Mars  were discovered by Professor Hall at Washington

 There is no credit given as to whom the  observer was who made the drawings “The   book was  prepared as a Science text book  for  schools.   Very interesting to read the  ideas of 1862 and what  we  understand today  with our modern in situ  exploration of Mars. 

[Stewart John Bean]

Hi, Just  found this thread and wondered the current status?

I use the itelescope network and might consider joining a BAA group

Stewart

[Stewart Moore]

Hello James,

I agree with Owen’s list and don’t think there are any other books I’d add. Many past editions of The Deep Sky Observer (the Webb Society in-house journal) will be found to contain articles on planetaries so it’s well worth joining Webb!  Also, if you use the Uranometria star atlas then the associated Deep Sky Field Guide to Uranometria (Willmann-Bell) gives useful short summaries of planetaries appearing in the atlas.

Hope this helps, Stewart

[Peter L J]

Hi Everyone,

Please could anyone tell me if it will be possible to view a recording of today’s Webinar after the event?  I particularly wanted to join Owen’s session today but unfortunately, I have a clash of commitments and cannot.  If a recording is made, please would anyone post the link so that I can access it tomorrow.

Many thanks and best wishes

Peter L Jennings

[Nick James]

The latest edition of the BAA Comet section newsletter, The Comet’s Tale, is now available for download from https://britastro.org/node/6812. The newsletter is freely available to all but it is backed by the BAA so if you enjoy reading it please consider joining the Association.

My thanks to everyone involved in this publication but particularly to the editor, Janice McClean, who has done a fantastic job of putting it all together and dealing with an, often distracted, section director along the way.

Comet C/2020 F3 (NEOWISE) features on the cover in a beautiful image from David Swan but it came a bit too late for inclusion inside. We’ll rectify that in the next edition.

I hope you enjoy reading it. As always, feedback is very welcome.

[Tony Morris]

Hi

Carbon composites can be tricky to mechanically fix together or join to other structures

For ideas have a look here:-

https://www.rockwestcomposites.com/shop/connector-accessories/carbonnect/fixed-connector/ce-cl-05-group

Tony

[Kevin Gurney]

Hi all,

I just thought I would let you know what I concluded after much experimentation with the Lhires on various reference stars and with/without filters

I bought a Baader orange filter (as per Robin’s suggestion) with a view to eliminating any higher order contamination and it worked well. Compared to the no-filter option, things at least seemed more consistent. But the prior inconsistency was, I thought, a clue in itself.

My backyard is subject to quite a lot of stray light, what with street lights, my drive lights on a motion sensor (the dog has to come  outside occasionally !)

I looked at some of the raw spectra in Pixinsight and used the various stretching tools to examine luminance gradients across the entire image. There was some evidence these were larger without the filter.

I then looked again at my efforts to seal the joints between the plate components with tape and there were still some possible entry points for light. In particular, there was a gap around the rear end where the grating sits. (I am talking <= 1mm of course). I used a plastic box, sprayed with matt black paint there. Then at the front there was a seam that I had left for some reason – I taped it up.

The result was that, without the filter, the ‘up tick’ at the red end was much reduced, although IRs were not quite as consistent as using the filter as well. I conclude that there probably was some light ingress and that this was reduced by the sealing at joints, and possibly further by using the filter (it’s near the sensor).

Kevin

[Robin Leadbeater]

I remember Gordon Myers talking about transformations (and extinction)  at the 2018 BAA/AAVSO joint meeting.

https://britastro.org/video/13862/14771

He put some numbers to the size of the effect for different systems he tested (6:39)

At the end of the day though these are still approximations dependent on the actual spectrum and can be way out in some circumstances. As an extreme (though real) example, a Nova spectrum dominated by H alpha. eg

https://britastro.org/specdb/data_graph.php?obs_id=650

A significant fraction of the H alpha flux would appear in the standard Johnson-Cousins V passband but would be completely missed by the Chroma version. Spectroscopy is much more straightforward 😉

Robin

[Eric Watkins]

Ernie, the details of that object are on the image. can’t locate original thread.  Nick also caught this one. I’m pleased that this thread has made you re-join the BAA. I have recently had my 50 yrs of continuous membership acknowledged.

It may be better to locate the original post and carry out any discussions  of this object  there to avoid confusion.

Eric

[stan armstrong]

arthritic fingers

[stan armstrong]

A week ago i wrote the following on the Facebook visitors page..

• …’Americo Watkins asked about a ‘Previous fireball’ to the Exploding one. If he gives me the time and date I will see if i have anything.. Further..’mike.german’ ..the disappearance of Power and Doppler in your graphs..is with the Eye of Faith..to be seen in the video track in attached shot’. My guess is that few members would expect to receive information via this method?

  I Attach a frame from my video of the event..and as my location is ‘Lngtde Offset’ from Nick and Eric hopefully this will help the accuracy of the path..

  I usually monitor UK Met on twitter for daily meteor mentions and IMO for others.. If Eric let’s me know time date of his previous interest Meteor I will see if i captured it too.. Apols for lack of immediate clarity but thought to Real time my input.

[stan armstrong]

A week ago i wrote the following on the Facebook visitors page..

• …’Americo Watkins asked about a ‘Previous fireball’ to the Exploding one. If he gives me the time and date I will see if i have anything.. Further..’mike.german’ ..the disappearance of Power and Doppler in your graphs..is with the Eye of Faith..to be seen in the video track in attached shot’. 

  I Attach a frame from my video of the event..and as my location is ‘Lngtde Offset’ from Nick and Eric hopefully this will help the accuracy of the path..

  I usually monitor UK Met on twitter for daily meteor mentions and IMO for others.. If Eric let’s me know time date of his previous interest Meteor I will see if i captured it too.. Apols for lack of immediate clarity but thought to Real time my input.

[Gary Poyner]

Hello Roy,

There is no formal way to join the VSS, as long as your interested in VS we’ll welcome you!  

To submit observations to the database, you will need an observer code and login details.  Have a read of this and it will advise how to go about it…

https://britastro.org/photdb/notes_submissions.php

I’ll leave it to one of the CCD observers to comment on your set-up, but it looks fine to me.

Don’t forget the VSS Circulars – free to everyone!  https://britastro.org/vss/VSSC_archive.htm

Gary

[Roy Lemmon]

Hi,

I have recently joined the BAA without much prior experience, but I am particularly interested in variable star observing. At the moment I am learning the basics by observing visually with a pair of binoculars, which is already challenging but fun ! I will submit some measurements soon but do you have to join the VSS to do this ?

However, I am thinking ahead and my aim would be to build a setup for CCD/CMOS variable star photometry. I was wondering if you had any comments about the suitability  of a setup such as:

• good quality German equatorial mount
• 80-100mm APO refractor
• guide scope
• CMOS mono camera with filters

My main question is whether a good quality refractor of this size is suitable for variable star CCD/CMOS observing ? With the above setup, I could also do some visual and imaging work. I am aware that a small refractor will be much easier to track with and balance the imaging equipment on for a beginner.

Thanks for any help.

Cheers
Roy.

[Carolyn Kennett]

Hi all, 

I want to thank everyone who got involved last month and sent me your image of the Moon and Venus. You may recall we are having a final attempt this month. Exactly the same as before except we would like you to image the Moon with Venus on Tuesday evening at 9.30pm (local time). 

Once all this attempt is over, we will work on the calculations from all the attempts and I will let you know how we have got on

thank you once again for your help. 

here is more details from last times request about what we are doing.

I am involved in a Heritage Lottery funded project where we have been celebrating the types of historical measurements astronomers used in the past. Part of this has been a parallax project where we have been asking people each month to take an image of the crescent moon and Venus. From this, we are going to use parallax (peoples locations around the globe and the orientation of the crescent to Venus) and measure the distance to the moon, much in the way the Transit of Venus was used to measure an astronomical unit. I know a few of you took part last month and I thank you for all your excellent images. We are asking people to take part again this month for a second attempt.

So if you would like to join in and it is safe for you to do so, can you take an image of the crescent moon and Venus on Saturday night at 8pm local time on your cameras and send it to us either here or my email carolyn@hird.net or @mayescreative on social media.

I will need to know your location of where the image was taken from, but a general location is fine eg Bristol.

more information can be found out about the project here

http://www.mayescreative.com/measure-to-the-moon.html

[David Swan]

It has passed on! This comet is no more! It has ceased to be …and joined the choir invisible. THIS IS AN EX-COMET. (Well not quite.)

10 x 20s, not great transparency, 2020-04-08T20:50:20.164 /UT of midpoint of exposure.

[Carolyn Kennett]

I am involved in a Heritage Lottery funded project where we have been celebrating the types of historical measurements astronomers used in the past. Part of this has been a parallax project where we have been asking people each month to take an image of the crescent moon and Venus. From this, we are going to use parallax (peoples locations around the globe and the orientation of the crescent to Venus) and measure the distance to the moon, much in the way the Transit of Venus was used to measure an astronomical unit. I know a few of you took part last month and I thank you for all your excellent images. We are asking people to take part again this month for a second attempt.

So if you would like to join in and it is safe for you to do so, can you take an image of the crescent moon and Venus on Saturday night at 8pm local time on your cameras and send it to us either here or my email carolyn@hird.net or @mayescreative on social media.

I will need to know your location of where the image was taken from, but a general location is fine eg Bristol.

more information can be found out about the project here

http://www.mayescreative.com/measure-to-the-moon.html

Attachments:

1. 

   measure-the-moon-image_orig.jpg
   

[John Cook]

Thanks for those pictures, that was the first BAA meeting that I attended, shortly after joining. I very much enjoyed it.

[Neil Morrison]

Deeply sorry to learn of Heathers death.  I am sure that every on in the BAA who  knew her and Nigel  will  join with me in sending their deepest Sympathy’s to Nigel.