„Lift up your eyes to heaven and see. Who has created these things? It is the One who brings out their army by number; He calls them all by name. Because of his vast dynamic energy and his awe-inspiring power, Not one of them is missing (…)”
Middle Eastern poem about the stars, 8th century BCE
Some fun: from 13 measurments on the raw images we get 1244.23 pixels as the Sun’s diamater. The pixel size is 4.06μm in this sensor so the size of the Sun’s image on the sensor is 5051.57μm (5.052mm). The focal length of telescope is 550mm. The Sun was 151,801,908km away when this image was taken. To get the diamater of the Sun: 5.052mm x 151,801,908km / 550mm = 1,394,369km (which is only 1% off of the best available measurements).
M101 / NGC 5457
Altough our images often (though unintentionally) feature small extremely far & faint galaxies, M101 is the furthest away target that we have choosen so far. It is a whooping 21 million light-years away! Something to think about: if M101 was bright enough for the naked eye to see, it would look almost exactly the same size as the full Moon; it is however 517,383,697,916,666x further away than the Moon; so, how big is it??
M42, M43 and The Running Man Nebula
A spiral galaxy like our Milky Way contains a diffuse interstellar medium of gas, dust, and trace amounts of heavier elements produced by old, dying stars. Sometimes these clouds collapse under their own weight, triggering star formation. In Orion there are about 700 stars in different stages of formation.
M44 / NGC 2632 / Cr 189
The Beehive Cluster is one of nearest open star clusters to Earth. Along with many main sequence stars it contains red giants and white dwarfs (which are much older stars). They are about 560 light-years away from Earth and on avarage 600 million years old.
C/2019 Y4 ATLAS, before it fell apart
ATLAS was a Kreutz sungrazer comet. These comets are fragments of a large comet that broke up centuries ago. Their orbits take them extremely close to the Sun, and because of that they often fall apart. Thousands of this family have been discovered so far, but most of them didn’t survive their meeting with the Sun.
Assorted throwaway pancakes
More often than not astrophotos don’t come out the way you planned them to. There are about a 200 steps involved in taking a picture, and they all have to be right. Also, often we need to experiment, finetune equipment or the sky is not good enough for long enough to finish a project. These are some examples of failures and experiments.