Thornbury

Archive

Heavens Above

The Elon Musk Starlink project is creating problems for observers of the night sky but do provide something else to look for. For details of the dates and times when Starlink satellites may be passing over, see "Heavens Above" (there is a link on this page):

https://www.heavens-above.com/

AstroMediaShop

A source for cardboard kits of scientific instruments, models, gadgets, and optical components for experiments, education, and astronomy. For practical experience, talk to Andy Pearson who has been diverting himself by making a cardboard spectroscope. You can get kits from Astromedia by going to this link (there is a link on this page):

http://www.astromediashop.co.uk/Home.html

Bill Beere's Photographs

In March 2020, one of our members, Bill Beere, managed to image comet PANSTARRS.

In his image it is a dot with a blue halo on the right, a little over halfway up from the bottom. Here are the images. First is Bill's Skysafari image taken from his ipad marked up with a rectangle showing the extent of the image viewed through the camera given the sensor size and focal length of the lens. Second is the Bill's image. Finally is an image showing the location of the comet.

(click on an icon to get a larger image)

Location of PANSTARRS on SkysafariPANSTARRS observationPANSTARRS observation marked up

Bill used the most basic Skywatcher equatorial "Go To" mount and inexpensive Canon camera with a secondhand manual focus Nikon 180mm f2.8 lens. The Skysafari app on his iPad showed where the comet was in the sky. Bill took 64 frames at 30s f2.8 ISO 1600. The comet could be seen in each frame but at 1600 ISO there was quite a bit of noise.

The images were processed by aligning the stars in each and then averaging all frames to reduce the noise using Photoshop. The background light pollution was also subtracted as much as is possible. The overall picture is similar to what was expected from Skysafari except for the comet's tail - a smudge was all Bill could manage.

The tracking was good enough to see faint stars well below magnitude 14 (the limit available in Bill's copy of Skysafari). The red at one end of the image is part of IC 1805 The Heart Nebula. The Soul Nebula is alongside but Bill could not image both and the comet with a 180mm lens.

In April, Bill was out again with his camera looking for Comet ATLAS from his garden in Alveston. Bill had a certain amount of difficulty finding it because it was not near any obvious marker in the sky – he finally found it between the Pole Star and Capella, which are over 40 degrees apart. Later, Bill discovered that ATLAS was breaking up. In fact it appears that it began breaking up a few days before Bill’s shot, so what he caught is a comet in the process of disintegrating.

(click on an icon to get a larger image)

Comet ATLAS

Bill was out again at the end of April and captured some star trails arcing round the north celestial pole The image is made from 15 four minute exposures. An enlargement of the center shows the offset of Polaris from the pole. In the photo, Polaris is at about 8 o'clock slightly offset by about three-quarters of a from true North. To emphasise this, Polaris is circled in the blown-up shot.

(click on an icon to get a larger image)

Star Trails Polaris Offset

Penumbral Eclipse of the Moon

There was a small penumbral eclipse of the full moon at around 7pm on Friday night, January 10th 2020. It was shot by one of our members with a digital camera fitted with a 400mm lens and mounted on a fixed tripod, exposure 1/125 seconds at f8, ISO 200. The faint penumbral shadow is across the bottom right hand corner up to the crater Tycho.

Penumbral Eclipse - January 10th 2020

Moon Rocks

In his talk on December 2nd 2019, Rod Jenkins mentioned an Open University book about Moon Rocks and the geology (it should be selenology, of course) of the Moon. It is little over sixty pages long, richly illustrated and covers a lot of what Rod explained in his talk. It is a free download from Apple iBooks if you happen to have a Mac, an iPad or an iPhone. Unfortunately it is not available in other formats.

Moon Rocks

Lunar Eclipse

Here are a couple of images of the July 16th 2019 Lunar Eclipse. They were taken by Rod Jenkins. The one on the left was taken at 2321 and on the right at 2359, as the eclipse was fading.

July 16th 23:21 July 16th 23:59

Computing Resources

In recent years there have been two talks about Computing Resources. In July 2017 Andy Pearson introduced the smartphone apps which he uses. Then, In January 2019, Andrew McLean gave his view. Notes from both presentations are available via links on this page.

Together these provide a comprehensive set of resources on which to build a library reflecting your own particular interests.

Eddie's Coaster

Eddie, who regales us with information on the sights to see in the sky, and events of historical interest, has also become well known for identifying an asterism in the constellation of Cassiopeia. This has become known as Eddie's Coaster for its shape which resembles a roller coaster. It recently gained some popularity having been identified in the Astronomy Press.

(click on a thumbnail to see a larger image)

Eddies Coaster 1 Eddies Coaster 2 Eddies Coaster 3

Links to Sounds and Images

Members of the group have found several links to interesting images and sounds. The URLs are here. There are links elsewhere on this page.

ESA's top 100 Hubble images:
https://www.spacetelescope.org/images/archive/top100/

Images from NASA are here:
https://images.nasa.gov/

Images of Jupiter from the Juno mission are here:
https://www.nasa.gov/mission_pages/juno/images/index.html

NASA sound files:
https://www.nasa.gov/connect/sounds/index.html

Link to OU Courses

The OU offers several free courses on Astronomy related topics. To see them, go to this link and click on Astronomy.

https://www.open.edu/openlearn/science-maths-technology/free-courses

BBC Radio 4

Th BBC retains some programmes in perpetuity. So, at the time of writing there are 177 editions of "The Life Scientific" online, and over 839 editions of "In Our Time". Get browsing.

BBC "In Our Time" is here:

https://www.bbc.co.uk/programmes/b006qykl

BBC "The Life Scientific" is here:

https://www.bbc.co.uk/programmes/b015sqc7