Distance Help

[crazzyroo]

Hi everyone,

I am pretty new to astronomy and having some real problems working out distances and where to find things. I have many maps and books (the links from this site are great) but still find it rather hard.
I can find the planets easy enough and have explored Orion but other than that I'm at a loss. The major constellations are not too much of a bother for me either, Crux, Leo etc.
To try and quantify what I mean a little better, on the free skymap it has Eta Carinae aprox 2cm above the Crux. Ok I can find the crux but whenever I travel in the rough direction towards the nebula I get lost :-(
Simply put, I don't know how to move what’s on the page in front of me to the sky above me.
Any and all help would be appreciated

Cheers

Nick

[prova]

Hi Nick

If your having trouble with maps and books, try some software for your PC.
There are alot of different types out there but you could try Stellarium as it's pretty good and free

http://www.stellarium.org/

Give it a go!

[programmer]

Try holding the skymap above your head. Even Stellarium, et al, don't look 'right' as you get closer to zenith. Unfortunately I gave in and bought some electronic help due to bright suburban skies...

[renormalised]

Hi Nick:)

Try to orient your sky map with what you see up in the sky. Looking for eta, just orient your map to how the Cross looks in the sky. You'll notice that eta Carina is off to the west of Crux by about 10-20 degrees. You can see it as a bright patch looking like a pale cloud. Don't look directly at it, use averted vision (i.e. look at it sideways), it's easier to see that way.

Keep using your charts in this way and soon enough you won't need them to find your way about, except for looking at the faint and fuzzies:)

[programmer]

Another thing to remember is look at the angular distance on the skymap, and use your fingers and hands to measure the distance.

Try the heading 'estimating angles by eye' below

http://www.geocities.com/angolano/Astronomy/PIinSky.html

[dannat]

You need to try & work out the field of view in your scope - then you can use this to calculate how mnay fov's you need to move in order to go from one object to the other. It's not perfect becuase the earth is a 3d sphere, and we are using a 2d square to approximate , but if you practice on some easy to see stars or the planets you will work it out. You will need an astronomy program to to get the coords of objects so you know how far they are apart. the ra/dec is listed for items if you click on them,

Nick , can you post some specs of your scope, focal length & what size eyepiece you troll around with

[AstralTraveller]

Nick,

This is a common problem which I'm sure we have all experienced, so don't be put off. A few good ideas:


Spend some time leaning the naked eye stars. I used to go into the backyard with my copy of Nortons Star Atlas and learn the major constellations and asterisms. Sometimes it is worth holding the chart over your head and lgoking up while doing this. This will save a lot of time when you have your scope out.
Binos are very useful. Many 'naked eye' stars won't be visible from a suburban backyard. Also many of the brighter fuzzies will be visible in even small binos (eg eta carina, omega centauri, orion nebula). Don't go for large high-power ones. They are heavy to hold and they magnify the inevitable shake of your hands. I think 8x40 is a good choice.
What I did was to work out the field of view (fov) of my finder scope an low power eyepieces (in degrees). I then used the scale on my chart (in mm per degree) to work out the diameter of a circle (in mm) that corresponded to each fov. I then drew circles of those diameters onto an overhead transparency sheet and coloured the area outside them black (this was very much pre-computer). I could then place the circles over the chart and work out what chunk of the sky I could see with either the binos, finder or scope. I then knew if star A was in the fov whether star B should or should not also be in the fov. I could also work out how many fovs I had to hop in a given direction to get from A to B.With a bit of practice I was soon star-hopping like a real astronomer ;).

cheers,
Dave

[GrahamL]

I'd try to take on board some of the brightest stars in the sky as well
Nick theres not lots of them that are visible at one time ..but if you can revisit them easily you will get a better idea how the rotation of the sky sits with the constellations and make finding your way back to referance points
for finding deep sky stuff within them.

http://astronomyspace.suite101.com/article.cfm/the_brightest_stars

take care

[crazzyroo]

Hi Everyone,

Sorry for the slow reply I have had computer issues. I just wanted to say thanks for all the help.
In answer to the question, what am I using: an 8" dob, f6, Highest Practical Power 406x, Faintest Steller Magnitude 14.2, Eyepieces 1.25” Super 25 and 10; I also have a x2 Barlow.

I would like to, if its possible find my way round the sky before getting some software. I can see how and auto track system would help with the planets.

Once again thanks for all the help, the night sky seems much better at the moment than when I started 4 months ago even if I can't take advantage of it!
Cheers

Nick