skypointer2000
The Edge of the Universe
A mostly dark frame with some faint fuzzy dots, flanked by a copy of the same with some incomprehensible labels? This is far from beeing the most beautiful image I ever published, but it easily qualifies as the most interesting! However, it certainly needs quite some explanation:
The image shows a section of sky (roughly 8.5° x 6.5°) in the border area of the constellations Leo, Virgo and Coma Berenices that is home to the northern part of the famous Virgo Galaxy Cluster. This cluster harbors roughly 1300 galaxies and forms the heart of the larger Virgo Supercluster, of which our Milky Way is an outlying member.
Just right of and below the center of the image is Markarian's Chain, a stretch of galaxies that is called a chain because, when viewed from Earth, the galaxies lie along a smoothly curved line. It is named after the Armenian astrophysicist, B. E. Markarian, who discovered their common motion in the early 1960s.
Markarian's Chain was my primary target for this image. As I was running late that evening, I decided not to set up my telescope, but to shoot with my 200mm lens from a tripod equipped with a simple iOptron SkyTracker. Not the most impressive setup and, considering that I was imaging from my light polluted backyard (#5 on the Bortle scale) with a too short focal length, I was not expecting much of a result.
After setting up, I just let the camera shoot away and went for my well-deserved nights rest. The next day, after sorting out the frames with clouds, aircraft or satellite trails, I ended up with 290 shots of 30s each, summing up to 2h25min of usable data. After stacking and processing these frames, I got the above image.
First, I was happy that my primary target was visible at all, but then I started to notice many small galaxies in the image. I therefore started to scrutinize the image systematically. You can see the result in the copy on the right side, where I was able to identify more than 150 galaxies (yellow labels).
Now I was truly impressed. I remembered the Hubble Deep Filed (HDF), showing thousands of galaxies in the early universe and started to think of my image as my personal deep field (PDF)…LOL
The imaged galaxies are roughly 50-60 million lightyears away from earth. While this is a huge distance (it means the light my camera caught was emitted just after the dinosaurs were extinct), it still is a rather small distance on the cosmological scale of the Hubble Deep field.
I started wondering if there are more distant objects in my image. After a dedicated search, I really found some exotic and much more distant objects (red labels). The most distant of them is a quasar named Q1227+120. It has a measured redshift of z=2.458. You can translate this into a cosmological distance of mindboggling 19.2 billion lightyears! The light of this quasar was emitted 11.1 billion years ago. That’s 4/5th of the time that has elapsed since the big bang!
Of course, you can find many images of similar objects taken with giant, professional telescopes. But when I realized that I had imaged an object that almost lies “at the edge of the universe” from a tripod in my backyard, with a simple DSLR camera and a 200mm lens, I was absolutely flabbergasted!
A word of caution:
Even in giant telescopes, these quasars (Quasi Stellar Objects) are just tiny, star-like dots of light. In my image, they are at the very limit of discernibility and you will have to download and open the image in full resolution to see them. But they are there – trust me!
Acknowledgement:
My star charts and planetarium programs were unable to go deep enough for the data of the image.
For my "research" I had to get access to professional quality data and found these in the "Aladin sky atlas" developed at CDS, Strasbourg Observatory, France → 2000A&AS..143...33B and 2014ASPC..485..277B.
Aladin is a free interactive sky atlas, allowing the user to visualize digitized astronomical images or full surveys, superimpose entries from astronomical catalogues or databases, and interactively access related data and information from the Simbad database, the VizieR service and other archives for all known astronomical objects in the field. It was developed for professional astronomers, but it is also a great toy for the interested amateur.
The Edge of the Universe
A mostly dark frame with some faint fuzzy dots, flanked by a copy of the same with some incomprehensible labels? This is far from beeing the most beautiful image I ever published, but it easily qualifies as the most interesting! However, it certainly needs quite some explanation:
The image shows a section of sky (roughly 8.5° x 6.5°) in the border area of the constellations Leo, Virgo and Coma Berenices that is home to the northern part of the famous Virgo Galaxy Cluster. This cluster harbors roughly 1300 galaxies and forms the heart of the larger Virgo Supercluster, of which our Milky Way is an outlying member.
Just right of and below the center of the image is Markarian's Chain, a stretch of galaxies that is called a chain because, when viewed from Earth, the galaxies lie along a smoothly curved line. It is named after the Armenian astrophysicist, B. E. Markarian, who discovered their common motion in the early 1960s.
Markarian's Chain was my primary target for this image. As I was running late that evening, I decided not to set up my telescope, but to shoot with my 200mm lens from a tripod equipped with a simple iOptron SkyTracker. Not the most impressive setup and, considering that I was imaging from my light polluted backyard (#5 on the Bortle scale) with a too short focal length, I was not expecting much of a result.
After setting up, I just let the camera shoot away and went for my well-deserved nights rest. The next day, after sorting out the frames with clouds, aircraft or satellite trails, I ended up with 290 shots of 30s each, summing up to 2h25min of usable data. After stacking and processing these frames, I got the above image.
First, I was happy that my primary target was visible at all, but then I started to notice many small galaxies in the image. I therefore started to scrutinize the image systematically. You can see the result in the copy on the right side, where I was able to identify more than 150 galaxies (yellow labels).
Now I was truly impressed. I remembered the Hubble Deep Filed (HDF), showing thousands of galaxies in the early universe and started to think of my image as my personal deep field (PDF)…LOL
The imaged galaxies are roughly 50-60 million lightyears away from earth. While this is a huge distance (it means the light my camera caught was emitted just after the dinosaurs were extinct), it still is a rather small distance on the cosmological scale of the Hubble Deep field.
I started wondering if there are more distant objects in my image. After a dedicated search, I really found some exotic and much more distant objects (red labels). The most distant of them is a quasar named Q1227+120. It has a measured redshift of z=2.458. You can translate this into a cosmological distance of mindboggling 19.2 billion lightyears! The light of this quasar was emitted 11.1 billion years ago. That’s 4/5th of the time that has elapsed since the big bang!
Of course, you can find many images of similar objects taken with giant, professional telescopes. But when I realized that I had imaged an object that almost lies “at the edge of the universe” from a tripod in my backyard, with a simple DSLR camera and a 200mm lens, I was absolutely flabbergasted!
A word of caution:
Even in giant telescopes, these quasars (Quasi Stellar Objects) are just tiny, star-like dots of light. In my image, they are at the very limit of discernibility and you will have to download and open the image in full resolution to see them. But they are there – trust me!
Acknowledgement:
My star charts and planetarium programs were unable to go deep enough for the data of the image.
For my "research" I had to get access to professional quality data and found these in the "Aladin sky atlas" developed at CDS, Strasbourg Observatory, France → 2000A&AS..143...33B and 2014ASPC..485..277B.
Aladin is a free interactive sky atlas, allowing the user to visualize digitized astronomical images or full surveys, superimpose entries from astronomical catalogues or databases, and interactively access related data and information from the Simbad database, the VizieR service and other archives for all known astronomical objects in the field. It was developed for professional astronomers, but it is also a great toy for the interested amateur.