Bank holiday weekend astronomy antics

The Sun - 25th May

A glimpse of the Sun on last Saturday morning, between the breaks in the cloud.

SOHO image mdi_sunspots

SOHO image of the Sun for comparison. Credit: NASA

Close up of sunspot 1756 - 2 - 26 May 10 - cropped

Close up of sunspot 1756, image obtained on Sunday 26th at 10:45. The main sunspot top right is similar in size as the Earth.

Looking at the large sunspot, a ‘light bridge’ can be made out on the LHS extending into the much darker central umbra, the width of the light bridge suggests that the sunspot is mature and on the downward phase in its life cycle.

Also, filaments can just be seen in the lighter pre-umbra surrounding the core of the sunspot. The filaments are magnetic in nature and radiate out from centre.

M57 – The Ring Nebula 

On the Sunday night, the skies remained clear and I was able to take the opportunity to do some observing with a new Mallincam astronomy video camera.

The shot below is my first attempt using this set up with the 200mm SCT telescope. This is a stack of about 10no single video stills each about 6-10 seconds in exposure length. The target is the ring nebula or Messier 57.

M57 - The Ring Nebula

M57 – The Ring Nebula

M57 is a planetary nebula in the constellation of Lyra, near the bright star of Vega and is currently visible to the south in a modest telescope.

The Ring Nebula is a shell of ionised gas which has been shed from a dying star originally similar in size to the Sun as it went through its red giant stage before turning into a white dwarf, which can just be made out in the centre of the image below.

The Ring Nebula is about 1 .3 light-years in diameter and is some 2300 light years away from us.

The blue green tinge is due to the presence of doubly ionised oxygen, whilst the outer red tinge is due to the presence of hydrogen.

The white dwarf at the centre is actually 200 times more luminous that our Sun and is made of primarily carbon and oxygen.


M57 location. Credit: Wikipedia

Below for comparison, is a Hubble Space Telescope image of the Ring Nebula


Credit: NASA


The Sun today

White light images of the Sun today, taken from home this morning.

Images obtained using a 72mm refractor fitted with a Lunt Herschel wedge with polarising filter.

A 1 minute movie file recorded using an Imaging Source AS41 astronomy camera, fitted with an IR filter and then stacked and processed in Registax.

The Sun is 1.4 million km in diameter and about 150 million km away from Earth. It takes light from the Sun 8 minutes to reach us.

sun0003 13-04-28 10-35-25-process3final

sun0002 13-04-28 10-34-01processed3final

Close up of sun spot group 1731 below, imaged using the same technique but with a 2x power mate. The larger of the sunspots below is about the same diameter at the Earth.

sun0005 13-04-28 10-42-38-sun spot 1731 close up process final

Solar and Heliospheric Observatory (SOHO) image below for comparison.

SOHO mdi_sunspots_1024

Credit: NASA

The Sun Today

The Sun today in White light:

The Sun processed 14.04

The first image is taken from home using a white light solar ‘herschel wedge’ on a 72mm refractor. Several clusters of Sunspots can be seen along with filaments (the lighter patches) most notible around the sunspot groups nearest the limb.

The second image is also in white light and taken today by the 1 billion Euro ESA/NASA Solar and Heliospheric Observatory (SOHO) which is a space based satellite that studies the Sun at various wavelengths. In the SOHO image below, the sun spot clusters are anotated and the Earth is shown for scale. North is up.

mdi_sunspots_1024 SOHO

Credit: ESA/NASA

Link to the SOHO website: