Archives for May 2023

Telescope: Meade SN10 at f/4, Orion Atlas EQ-G

Camera: QHY 268c, Mode 0, Gain 30, Offset 30, 0C

Filter: GSO IR Blocking Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 11x300sec, saved as FITS

Darks: 32×300 sec

Flats: 64×0.1 sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, fair transparency

Lensed Sky Quality Meter: 18.5 mag/arc-sec^2

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: SharpCap Pro, Nebulosity, Deep Sky Stacker, Photoshop

Supernova 2023ixf in M101 is a type II supernova, the result the core collapse of a massive star. The supernova was discovered on May 19^th while it was at magnitude 14.9. It quickly brightened to magnitude 11, which is where it is at now and within easy reach of modest size telescopes. Over the next few weeks and months it will slowly fade from sight.

Note that this is a photometric image, meaning that is has been processed to preserve the relative brightness of the stars and galaxy, so this is what the field would look like through a large telescope under a dark sky. The supernova is in the outer arm to the lower left of the core and a little bit brighter than the core. This shows how this single star is brighter than all of the billions of stars that make up the host galaxy and is even brighter than the million of stars that are crowded around the galaxy’s core. Also consider that all of the other stars in the field are in our own galaxy and none of these are more than a few thousand light years away. Note that M101 lies above the galactic plane and when we are looking in this direction intergalactic space is only a few thousand light years away, so none of the stars in this field can be farther away than that. The supernova is comparable to many of these local stars and is brighter than many of them, yet the host galaxy is 27 million light years away! That almost 10,000 times farther away that the local stars, yet is appears to be of comparable brightness!

 

The same image with the location of the supernova marked.

 

The same image, this time processed as a more conventional deepsky image to bring up the faint details. It does hep show the beautiful color and structure of the galaxy, but you can see how it suppresses the relative brightness of the supernova.

Neat stuff.

M101 is currently high overhead as the sky darkens.

 

Telescope: Meade SN10 at f/4, Orion Atlas EQ-G

Camera: QHY 268c, Mode 0, Gain 30, Offset 30, -10C

Filter: GSO IR Blocking Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 56x120sec, saved as FITS

Darks: 32×300 sec

Flats: 64×0.1 sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, poor transparency, smoke

Lensed Sky Quality Meter: 18.1 mag/arc-sec^2

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: SharpCap Pro, Nebulosity, Deep Sky Stacker, Photoshop

M3 is a beautiful example of a globular cluster in a relatively lonely stretch of sky. The cluster is a member of the galactic halo and spends much of its time orbiting well outside the plane of the galaxy. It is presently 33,000 light years away from us, 40,000 light years from the galactic core, and 33,000 light years ‘above’ the galactic plane. Home to about 500,000 stars, M3 is relatively young as globular clusters go with an estimated age of 8 billion years.

Ugh, despite the ‘clear’ skies, we are currently dealing with a thick veil of smoke from forest fires in Canada. I was very surprised at how well my cameras could punch through the poor conditions and still give a decent image. Imaging diffuse objects like galaxies is not an option for me right now, but clusters seem to do well, and stellar targets like clusters, double stars, and asteroids are still nice visual targets.

M3 is currently well placed high in the northeast as twilight deepens.

Telescope: Meade SN10 at f/4, Orion Atlas EQ-G

Camera: QHY 268c, Mode 0, Gain 30, Offset 30, -10C

Filter: GSO IR Blocking Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 52x120sec, saved as FITS

Darks: 32×300 sec

Flats: 64×0.1 sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, poor transparency, haze

Lensed Sky Quality Meter: 18.5 mag/arc-sec^2

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: SharpCap Pro, Nebulosity, Deep Sky Stacker, Photoshop

This is M13, the Great Cluster in Hercules. Also in the picture is the spiral galaxy NGC 6207 (Mv 11.6) in the upper left corner, and about halfway between NGC 6207 and M13 is the tiny edge-on galaxy IC 4617 (Mv 15.2) . If you look carefully at M13 you can see a dust lane to the lower left of the cluster. This is a very unusual feature for globular clusters and it is not clear if this is actually associated with M13 or simply front of the cluster.

M13 currently rises in the northeast during the early evening.

Telescope: Meade SN10 at f/4, Orion Atlas EQ-G

Camera: QHY 268c, Mode 0, Gain 30, Offset 30, -10C

Filter: GSO IR Blocking Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 20x300sec, saved as FITS

Darks: 32×300 sec

Flats: 64×0.1 sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, poor transparency, haze

Lensed Sky Quality Meter: 18.4 mag/arc-sec^2

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: SharpCap Pro, Nebulosity, Deep Sky Stacker, Photoshop

M51 is a beautiful face-on spiral galaxy in Canes Venatici, just south of Alkaid, the bright star that lies at the eastern end of the Big Dipper. The spiral arm that appears to connect M51 to the nearby companion (NGC 5195) is a bit of an illusion. The companion actually lies behind M51, and if you look closely you can see that the spiral arm is silhouetted against the background galaxy. Modern observations and computer modeling suggest that the companion has made at least two passes through the main disk of M51. During the first, it approached M51 from behind, passed through the face of the galaxy, swung around in an orbit that took it in front, and then back through the disk where it lies now behind M51. These passes set off bursts of star formation that gives the arms of M51 their beautiful blue color.

M51 currently high overhead during the early evening.