Hi,
For my holiday reading I'm checking out "The Night Sky" by Steve Massey. I've only made it in a few pages before getting myself all confused - the equatorial system is tying my brain in knots!
Here's my problem: (paraphrasing from book..)
- "earth rotates through 360º in 24 hours, hence one hour of arc = 15º"
I get it. 15x24=360. Simple mathematics.
- "each hour is further subdivided into minutes and seconds of arc"
I get it. Sounds perfectly reasonable.
Now comes the bit where my brain gets jammed:
- "For example, 1º of sky is equal to 60 arc minutes and 1 minute of sky is equal to 60 arc seconds"
I don't get it.
I thought 1 hour of arc = 15º.
given that, shouldn't 60 arc minutes = 1 arc hour = 15º?
I don't know where my thinking is going wrong here, can anyone help?
