navigating around the stars

rabbitguts · #1 10-12-2009, 09:12 PM

looking for somewhere to start regarding navigating aound the stars, some of the terminology i do not get and the orientation points, is there a website that can help?? thanks

barx1963 (Malcolm) · #2 10-12-2009, 09:29 PM

OK where to start? Firstly, what equipment, books, charts etc do you have already? Secondly, what terms are causing confusion?

If I was starting from stratch the first thing to get is a planisphere, will help you to identify the brighter stars and constellations and assist with learning how it all "moves". I found the idea of North, South, East and West very confusing when applied to the sky when I first started. Just remembering that moving towards a pole if South (or North) and moving perpendicular to that movement is East or West helps alot, after a while you get the idea!

mental4astro (Alexander) · #3 10-12-2009, 09:38 PM

G'day rabbitguts,

to IIS. Love the monica! I love rabbits too, on the dinner plate though. Food...

Back to what we're here for. Here is a link to a DIY planisphere I lifted from one of the Beginners forum stickies:

http://www.asahi-net.or.jp/~zs3t-tk/...lanisphere.htm

A planisphere will show you what constellations are up at what ever time of year and pretty much date. This one you can make up for what ever latitude you like! These simple devices also tend to show only the brighter stars to reduce confusion.

The top thing about these is that you could well end up using it the whole of your astro 'career'. I still use one after 25 years to plan sessions.

A compass will help initially to orientate yourself.

This next link is to a good beginners star atlas, also from the same sticky. It is more complex, but used in conjunction with the planisphere your start to finding objects will progress quickly. This is how I started.

http://www.asahi-net.or.jp/~zs3t-tk/atlas/atlas.htm

More complex atlases are available, but too confusing as they then show
stuff that is way out of reach for most beginners: no use showing a 12th magnitude galaxy if a 7th magnitude one can't be found. There is time for this.

If you would like a computer based program, try Stellarium:

http://www.stellarium.org/

The planisphere though is a very good start to find your way around,

.

Enjoy,

Mental.

michaellxv (Michael) · #4 10-12-2009, 09:40 PM

Your best resource is probably the local library. Mine has a good selection of books, i've never read more in one year in my life. Most astronomy related books will give you some explanation, some more detailed than others. Best thing is you don't have to spend a fortune on books or worry if you are getting the right one.

Robh (Rob) · #5 10-12-2009, 10:37 PM

Here's a few things to keep in mind ...
1. Maps of the sky have the horizontal scale (right ascension) in hours. Each hour is 15 degrees. The vertical scale (declination) is in degrees. The hardest thing for beginners is to picture the size of a constellation. If you hold your arm straight out to the sky, the width of your thumb is about 2 degrees, the width of your clenched fist is about 10 degrees, clenched fist with thumb extended is 15 degrees and the total width of your hand with thumb and fingers spread out is about 20 degrees.
2. Maps are generally oriented with the north celestial pole at top. Looking north, the maps will be upside down. Looking south, the constellations will rotate about the south celestial pole so maps will change orientation.
3. Due to the rotation of the Earth, the sky and its constellations will appear to move from east to west at 15 degrees each hour.
4. The largest spots on each map are the brightest stars. Try to locate them using a planisphere or Stellarium as mental4astro recommended. Find the more obvious constellations e.g. Crux (Southern Cross), Orion, Canis Major or the Great Square of Pegasus.
5. Once you can recognise and find new constellations, then you can start to look for component binary stars, clusters and later on galaxies. Use binoculars to help you spot and identify the brighter clusters.

Regards, Rob

Vartigy (Aaron) · #6 16-12-2009, 10:36 AM

If you have an iphone or ipod touch, there is a free app called distant suns 'lite'. Fantastic bit of gear.
Input your long/lat coords and away you go. It has real-time update and shows everything from planets to dsos.
I've left my starmaps behind for this.
Good thing about this app on the iphone and not the ipod touch is that you can make use of the gps functionality such that which ever direction you're facing with the unit, it will show you that part of the sky.