Cosmolgy- Density of the Universe

AI Thread Summary
The discussion centers on calculating how far one could see in any direction before encountering a galaxy, given an average galaxy density of 0.9 Mpc^-3 and a galaxy diameter of 30 kpc. Participants agree that, under these conditions, it is likely that a galaxy would be encountered regardless of the direction of observation. Clarification on units reveals that kpc stands for kiloparsec and mpc for megaparsec. The conversation emphasizes the implications of these measurements in understanding the universe's structure. Overall, the consensus is that the density suggests galaxies are ubiquitous in the observable universe.
EP
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Assume the universe has an average galaxy density of p=0.9 Mpc^-3. Each galaxy has a diameter of 30 kpc. How far would you see on average in any direction before your line of sight would hit a galaxy? Assume a Eucledian spcae and infinitely large and infinitely old universe.

Help get me started.
Thanks

My guess is the answer is that no matter where you look you'll see a galaxy under these conditions.
 
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EP said:
Assume the universe has an average galaxy density of p=0.9 Mpc^-3. Each galaxy has a diameter of 30 kpc. How far would you see on average in any direction before your line of sight would hit a galaxy? Assume a Eucledian spcae and infinitely large and infinitely old universe.

Help get me started.
Thanks

My guess is the answer is that no matter where you look you'll see a galaxy under these conditions.
What units are are kpc and mpc?

AM
 
Kiloparsec and Megaparsec
 

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