Ask An Astronomer Anything At All About Astronomy

For those who haven't been paying close attention, you might want to take a look at the new Q&A section. Here I collect the questions people have asked on the interweb which I have attempted to answer. The first batch are all those I could remember answering.

Since this is a very regular occurrence, I'll aim to post weekly updates. I only include my own answers where the alternatives provided were wrong or I felt my own answer added something useful.

For those who did notice the Q&A page, you should also notice that there's now a contents section with internal page links to each question, which is nice.

This week's additions with even more concise answers :

1) Are we sure the acceleration of the expansion of the Universe is real ?
Probably.

2) Could you pee all the way around the Moon ?
No, but you could around a 2km wide asteroid.

3) How many aliens are there ?
Fifty seven. Six. A million and two. How many would you like ?

4) Could galaxies actually be moving because space is flowing ?
No. It's not that wibbly-wobbly.

5) Is the Universe infinite ?
Could be, but I'd rather it wasn't.

6) How can we prove dark matter exists ?
We can't, yet. Lots of evidence says it exists, and direct detection experiments are underway.

7) How can we detect gravity ?
By dropping cats into a black hole, possibly with lasers. Mew mew mew !

8) What's the latest progress in detecting dark matter ?
Nothing conclusive.

9) Will NASA's pet-rock-on-a-leash need a push to keep it in orbit ?
It will need a few pushes to put it in orbit. After that it will run around in circles all day for no reason, just like a real dog.

10) Do stupid astronomy memes matter ?
Yes they do. I wish they didn't, but they do.