Stellarium

[Ian Pegler]

Just to let you know that version 0.11.0 is now available from the website.

Ian

[Ian Pegler]

I must tell you I just downloaded MicroSoft ICE which is a free photo-stitching app for Windows. I literally just opened over 100 image-files and it stitched them together perfectly without any further input from me.

Talk about nifty !!!

The only thing I would say, is that it requires other things to be downloaded and installed first (.NET framework etc. etc.). When you run the installer, it will prompt you to download the other things, if you haven't already got them, and take you to the download sites.

Having stitched your photos you can then export it to a PNG, giving it an appropriate width value in pixels (e.g. 4096) and proceed as usual.

I'm well impressed !

Ian

[Ian Pegler]

Stellarium version 0.11.1 is now available.

http://www.stellarium.org

Ian

[Ian Pegler]

Yet another fly in the ointment of life...

Cross Quarter days

I was looking at the value of Right Ascension (of date) for the Sun at the Solstices and Equinoxes. It all seems straight forward enough:

Vernal Equinox (March 21st): Right Ascension of the Sun = 00h00m00s
Summer Solstice (June 21st): RA = 6h00m00s
Autumnal Equinox (Sept 21st): RA = 12h00m00s
Winter Solstice (Dec 21st): RA = 18h00m00s

All well and good. The problem comes with the cross quarter days. In theory the values for Right Ascension of the Sun should be:

Samhain: RA = 15h00m00s
Imbolc: RA = 21h00m00s
Beltane: RA = 03h00m00s
Lughnasadh: RA = 09h00m00s

Right Ascension (RA) coordinates are based on the equator not the ecliptic (why did no-one point this out??).

To find the position of the quarter days or cross quarter days, you need to use coordinates based on the ecliptic, not Right Ascension.

It's unfortunate that Stellarium doesn't use ecliptic coordinates because that would make things a whole lot simpler. So you're going to need an astrology app like Astrolog or Zet to find the moment of the event, note down the date & time, then if you want to view the event under Stellarium, plug in that date & time.

So for example, the cross-quarter day linked with Samhain is at 15 degrees Scorpio using ecliptic coordinates. You should find that for 2011 this happens on Nov 7th. Using your chosen piece of Astrology software, find out the time that the Sun is at 15 degrees in Scorpio (I make it about 18:47 GMT). When you plug that into Stellarium you should find that at that same moment the RA of the Sun is about 14h50s or thereabouts, not 15h00s.

There are different ways of reckoning the cross-quarter days, however so this also needs to be taken into account.

Ian

[Ian Pegler]

Version 0.11.2 is now available, lots of bug fixes, some new things but most of these are just relevant for modern astronomy.

http://stellarium.org/

Ian

[Ian Pegler]

Version 0.11.3 is now available - new features include a grid based on the ecliptic. Very handy!

Also loads of bug-fixes, and it loads up a lot faster.

http://www.stellarium.org

Ian

[Ian Pegler]

Version 0.11.3 is now available - new features include a grid based on the ecliptic. Very handy!

There is still a problem, because if you type in a historical date, the Sun actually moves away from the ecliptic!

The ecliptic grid is based on our own epoch (hence J2000) rather than a past age. No use to me at all!

Ian

[Ian Pegler]

Stellarium version 0.11.4 is out. There is now a download for 64-bit Windows machines.

I recently created a Stellarium landscape for the summit of Glastonbury Tor.

https://stellarium.org/en/landscapes-europe.html

Ian

[Ian Pegler]

Latest release: 0.12.0

Ian

[Ian Pegler]

Recently released 0.12.1

Ian

[Ian Pegler]

Stellarium 0.13.0 is available.

I recently created a landscape for Strata Florida abbey.

https://stellarium.org/en/landscapes-europe.html

Ian

[Grahame]

I'm not having much luck with Stellarium 13.0 - I keep getting an error message saying 'no disk in drive F' that won't go away, so I've had to uninstall it. This is on Windows 8.1 mind you - maybe I need a 64-bit version?

[Ian Pegler]

Stellarium 0.14.0 is out now. Some new features very pertinent to the kind of work we're doing, including
improved precession and an ecliptic grid (of date).

Ian

[Grahame]

Gosh, it's been a while since I did a Stellarium landscape, I'd forgotten how much fiddling around was involved. However, I have finally made a landscape for Swinside stone ring in Cumbria, from a panorama I took 5 years ago!

Click Here for the direct download link, or HERE for a collection of other fine UK landscapes created by me and Ian Pegler.
For the complete worldwide collection of landscapes, visit the Stellarium landscapes page.

I used two programs that I hadn't used before to make this landscape, and I actually found the process easier than using GIMP, my previous go-to paint package. The first was Microsoft's Image Composite Editor (previously recommended by Ian), used to composite the panorama. This has the advantage in that you can slide the image left and right during the process so that it is extremely easy to get the East point lined up with the left-hand edge of the picture (essential for this type of landscape). In this case, I based the east point on the Alexander Thom survey of the site. There's also a handy tall stone pointer marking the North in this circle, so it wasn't too hard to get right.

The second program was Paint.net, which I found much easier to use than GIMP. The basic program is fine for this purpose, but you can also download a ton of effect plugins from the forums.
NOTE only download add-ins from the official forums as the internet is rife with virus-laden fake plugins for Paint.net.

[Grahame]

Flushed with that success, I've just re-done my Stellarium landscape of Sighthill stone circle in Glasgow, a modern astronomically-aligned ring constructed in 1979. The old landscape was the first one I ever made, and was taken with my old digital camera so the resolution was pretty poor. I took this panorama in December 2013 - the best time to view the circle is when the trees are bare, although that does make it a complete pain to edit the panorama for Stellarium as you have to manually erase all the bits of sky between the branches. I suddenly remembered why I hadn't updated this one at the time! (note to self: no more panoramas involving trees)

The Sighthill area is scheduled for a new housing development so I don't know how long the circle is going to last; however due to pressure from local pagans and others, including the designer Duncan Lunan, the Council have promised to preserve the stones and recreate the circle somewhere in the vicinity, although it's unlikely to enjoy such good panoramic views as it does at present.