This fall and winter was dedicated to imaging the Cepheus area with a Hydrogen Alpha narrow band filter. However, at the low latitude from where I observe, Cepheus gets low on the horizon pretty early in winter. So I had to find another target to image during the late night. I decided to revisit anContinue reading “Visiting the Horse Head nebula in Narrowband”
Category Archives: Astronomy
Objects moving in the sky
When close to both their perhelion and to Earth, comets can have a fast motion relative to the background sky. This is also the time when they are the brightest. If using very fast optics (the C11 + hyperstar, at f/2 for 280mm of aperture is well suited), it is possible make a video ofContinue reading “Objects moving in the sky”
Taking a picture of the most luminous blazar flare ever recorded.
A blazar is an active galactic nucleus with a relativistic jet (a jet composed of ionized matter traveling at nearly the speed of light) directed towards the observer. CTA 102 is a blazar-type quasar discovered in the early 1960s in the constellation Pegasus. It is also one of the two great false alarms in theContinue reading “Taking a picture of the most luminous blazar flare ever recorded.”
Simeis 147, the Spaghetti nebula
Simeis 147, also known as the Spaghetti Nebula or Sharpless 2-240 is a supernova remnant in Taurus. It was discovered so late (1952), because it’s dim. I was curious to see what was possible on the low end from my site with the Borg 55 and a H-Alpha filter. So here it is. I haveContinue reading “Simeis 147, the Spaghetti nebula”
Orion H-Alpha mosaic
This is my first H alpha mosaic, using the Borg 55. It was acquired over the winter of 2018-2019, and one of the goals was to image the Barnard loop (Sh 2-276), a supernova remnant. The mosaic is centered on the horse head dark nebula (Barnard 33). https://erellaz.com/wp-content/uploads/2020/05/Barnard33.jpg
A visit of Cygnus the swan
After finishing the Cygnus H-Alpha Mosaic, I extracted & rotated the iconic objects present in the image, at various scale to best showcase them. The full scale mosaic can be downloaded from the link below, and it contains all the objects shown on this page. https://erellaz.com/wp-content/uploads/2020/05/Cygnus_final_Pixinsight-1.jpg
Processing the Cygnus Mosaic
Processing the 30 tiles Cygnus mozaic was a bit of a challenge. First there is the logistic of handling about 2,000 frames and then the Borg 55 f3.6 astrograph exhibits strong field distortion making the merge of the images difficult, particularly where the corners overlap. For each of the 30 tiles I ran the PixInsightContinue reading “Processing the Cygnus Mosaic”
Acquiring the Cygnus mosaic
Most of the summer and fall of 2019 was spent imaging the Cygnus region in Hydrogen Alpha. I ended up doing a 30 tiles mosaic, with one hour of integration per tile. Each tile is made of 60 subs of 1 minute each, stacked together. The image covers a very wide field of 22×19 degrees,Continue reading “Acquiring the Cygnus mosaic”