The Image Index is a system based on likes received on images, that incentivizes the most active and liked members of the community. Learn more.
The Contribution Index (beta) is system to reward informative, constructive, and valuable commentary on AstroBin. Learn more.
Dates:April 16, 2018 , April 25, 2019 , April 27, 2019 , May 3, 2019 , May 27, 2019 , May 29, 2019 , May 30, 2019 , June 4, 2019 , June 6, 2019 , June 25, 2019 , June 27, 2019 , July 2, 2019 , July 6, 2019
Frames:
Baader L: 57x1800" bin 1x1
Baader RGB Filters: 87x600" bin 2x2
Integration: 43.0 hours
Avg. Moon age: 17.64 days
Avg. Moon phase: 23.45%
Bortle Dark-Sky Scale: 2.82
Mean SQM: 21.65
Astrometry.net job: 2810723
RA center: 16h 35' 57"
DEC center: +66° 13' 4"
Pixel scale: 0.512 arcsec/pixel
Orientation: 0.861 degrees
Field radius: 0.197 degrees
Resolution: 1957x1963
Data source: Traveller
Abell 2218 galactic cluster in the constellation Dragon, is about 2.1 billion light years from Earth (cosmological redshift z = 0.17).
The photo shows a set of small yellowish galaxies. For a particular identification of details is very helpful here is this work:
http://iopscience.iop.org/article/10.1086/177995/pdf
No. 289. The brightest and most easily detectable arc. z = 1.03. Visible even on some individual subs.
No. 359 /328. The first is a brighter and more easily detectable red arc, the second is a weaker counter-image of the first arc 359. z = 0.7. The complex itself (plus no. 337/389 visible in the HST image), according to scientists, is an image of a background spheroidal galaxy.
No. 384 /468. The first is still bright, the second is very weak counter-image of the first arc. z = 2.8. The value of the redshift is such that the object will move away from us at a speed of 261,000 km/s, which is already 87 % of the speed of light.
No. 444. Much weaker than its neighbour arc 384. z = 1.1. Magnitude in red 23m.
You have no new notifications. |
This page or operation is not available at the moment, because AstroBin is in READ ONLY mode. For more information, please check out our Twitter feed: https://twitter.com/AstroBin_com
This feature is only offered at higher membership levels.
Would you be interested in upgrading? AstroBin is a very small business and your support would mean a lot!
If this user has been harassing you, and you shadow-ban them, all their activities on your content will be invisible to everyone except themselves.
They will not know that they have been shadow-banned, and the goal is that eventually they will get bored while having caused no harm, since nobody saw what they posted.
You will remove your shadow-ban on this user, and their comments, messages, etc, will appear again on your content.
Such limitation improves the website as a whole by discouraging people from creating fake accounts to like their own content. Thank you for understanding!
Currently, your Image Index is .
To learn more about the Image Index, please visit the FAQ page. Thanks!
Comments