How do we know that superclusters are the largest structures in the universe?
We know (or at least, strongly suspect) that superclusters and similar-sized features are the largest structures in the universe because:
1) We don't directly observe light from structures that are larger than that.
2) The velocities of galaxies don't seem to be influenced by structures that are more than a few hundred million light-years away. From that you can infer that there *are* no structures with sizes bigger than that.
3) Our present understanding of how large scale structure formed in the universe (which is backed up by other observations, independent of those from #1 and #2) doesn't allow for even larger structures. Given how long the universe has been around, and how fast it's expanding, you can figure out how large the largest structures that have had time to form would be. That size is about the size of superclusters.
Get More 'Curious?' with Our New PODCAST:
- Podcast? Subscribe? Tell me about the Ask an Astronomer Podcast
- Subscribe to our Podcast | Listen to our current Episode
- Cool! But I can't now. Send me a quick reminder now for later.
- What is the largest structure in the universe?
- What are collections of galaxies called?
- Is the Great Wall the largest galaxy cluster?
How to ask a question:
If you have a follow-up question concerning the above subject, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.Table 'curious.Referrers' doesn't existTable 'curious.Referrers' doesn't exist
This page has been accessed 23730 times since June 7, 2003.
Last modified: June 7, 2003 4:05:44 PM
Ask an Astronomer is hosted by the Astronomy Department at Cornell University and is produced with PHP and MySQL.
Warning: Your browser is misbehaving! This page might look ugly. (Details)