Hi Steve,
You are not the first to ask a question like this and I suspect you will be far from the last!
A 4" refractor is a fine telescope and it can show you a great deal in the night sky. In _perfect conditions_ it will show stars as faint as mag 13 hundreds of double stars and open clusters, dozens of globular clusters and a good view of several dozen galaxies -- hundreds more galaxies as tiny dim patches of fuzz.
The strong suit for an instrument like this will be lunar and planetary observing and in _perfect conditions_ you can expect to see a good amount of detail on Mars and detail on the moon as small as about 2km diameter.
The problem this time around with Mars (and the next few times) is that perfect conditions will be shrinkingly rare. This apparition, at best Mars will be only 30-odd degrees above the northern horizon. Not nearly high enough to get good steady seeing except on rare occasions. Coupled with that is Mars pretty small size this time (16-odd arc-seconds). So, more often than not it will be a small, bright orange squiggly dot with only gross detail like the polar cap/hood and very dark features like Syrtis Major being occasionally visible -- Sorry to disappoint but them's the plain facts!
If it is any consolation, those observing with much larger 'scopes in Australia and NZ will see little more than your 4" will show on most nights because of that very low elevation at culmination. Seeing all the detail Mars has to offer is more difficult than it appears. The albiedo markings on Mars are in the main very subtle and experienced observers do better than novices only because they know exactly what to look for.
If you want a custom made map of the side of Mars facing you for your time and location, download this terrific little piece of software called "Mars Previewer" which is available here:
http://www.skyandtelescope.com/resou...tml?c=y&page=2
To get an idea of what the Mars should look like when viewed in good conditions through different 'scopes look here:
http://astronomy.concreteairship.com...marsseeing.htm
And Jupiter:
http://astronomy.concreteairship.com...iterseeing.htm
And Saturn:
http://astronomy.concreteairship.com...turnseeing.htm
Hope this is some help.
Look forward next year to your views of Saturn and Jupiter which will be much more satisfying.
Best of luck with the new toy and be certain to keep us up-to-date with some observations and what you saw.
Best,
Les D
Contributing Editor
AS&T
