Scioly.org

sciolykid101 wrote:

crabnebula143 wrote:Does anyone know the last year galaxies was an event for astronomy???
thanks!

the galaxies for 2010 is posted on the thread already also variable stars was 2009, not galaxies

E probably wants to know how long ago it was the last time that galaxies were the topic of astronomy. As do I. I think I remember reading that there are three astronomy topics on a three-years-each rotation, so perhaps it was back in 2001? That's largely speculation, though.

Think '03.

Thank you!

crabnebula143 wrote:Aren't cepheids and RR Lyrae's used to determine distances to galaxies?

Yeah, so basically the event this year is mostly about galaxies. I'm really happy that were off the topic of variable stars. I've been stuck with variable stars for too long. Good thing the board made something new!!!

I feel really stupid for asking this but then why are they putting in binaries, such as M33 X-7?
Thanks!

Probably because Epsilon Aurigae is still on the list. They probably wanted to have more than one binary so there could be another catagory. It would be weird if there was only one binary system.

Anyone have any suggestions for good books about galaxies? I'm kind of new to the event.

Does anyone know why A-type stars have the strongest H absorption lines? thnx.

crabnebula143 wrote:Does anyone know why A-type stars have the strongest H absorption lines? thnx.

Any hotter than A and helium becomes dominant.

Any hotter than A and the Hydrogen completely dissociates with its electrons, so there can be no absorption lines