What scope needed to see Io?

A place to hang out and chat about astronomy

What scope needed to see Io?

Postby cloudcover sucks » Fri Feb 24, 2006 11:40 pm

Hi,

I think Io is a nice moon to look at in pictures, but is it possible for an amatuer astronomer like me to buy a scope capable of seeing it up very close with high detail or is it too far away?

I would like my next scope to be a catadioptric with a large mirror. Would a 12 or 16 inch catadioptric be able to reveal in fine detail the geographic features of Io or do you need a lot more aperture? Also, what is the best way to get more aperture for lowest price?

Al
cloudcover sucks
 
Posts: 25
Joined: Mon Feb 13, 2012 6:24 pm

RE: What scope needed to see Io?

Postby gammalog » Sat Feb 25, 2006 12:13 am

Hi Al and welcome to the Forum.

I don't think that any Earth based telescope will show any surface detail on Io, or any other of Jupiter's moons. It's very small, compared to it's mother Planet, and an awfully long way from us,. We see these moons as points of light.

The simple answer to your question regarding the largest amount of light gathering power per £ spent, is without doubt, the Dobsonian Reflector.
I
gammalog
 
Posts: 840
Joined: Mon Feb 13, 2012 6:21 pm

RE: What scope needed to see Io?

Postby sftonkin » Sat Feb 25, 2006 6:20 am


[quote]ORIGINAL: cloudcover sucks
Would a 12 or 16 inch catadioptric be able to reveal in fine detail the geographic features of Io or do you need a lot more aperture? [/quote]

A 95-inch Ritchey-Chrétien in low Earth orbit ought to do the job nicely. [:D] (Actually, there [i]was[/i] some talk a few years ago, amongst some (wealthy) amateurs in the USA, of collaborating to construct and fund an amateur space telescope of, IIRC, about 1.5m)

Seriously, Io has an apparent diameter of about an arcsecond so, to see significant detail, you need to resolve down to at least about 100 milliarcsec. Even on the best nights, at the best sites in the world, the atmosphere limits seeing with passive optics to about 250 milliarcsec (HST gets down to about 50 milliarcsec). Seeing from Britain is usually of the order of several arcsec (I recall only two nights of sub-arcsecond seeing), so you are either going to need to beat the atmosphere by going outside it, or you are going to need active optics.

[quote]
Also, what is the best way to get more aperture for lowest price?
[/quote]

What Dave said (Dobsonian).
sftonkin
 
Posts: 2826
Joined: Mon Feb 13, 2012 6:22 pm

RE: What scope needed to see Io?

Postby cloudcover sucks » Mon Feb 27, 2006 8:50 pm


Thanks to you both for the welcome and replies. I'll be sending in my order for a 95 incher then [:D]! In my dreams....

All the best.

Al
cloudcover sucks
 
Posts: 25
Joined: Mon Feb 13, 2012 6:24 pm


Return to General

Who is online

Users browsing this forum: No registered users and 1 guest