Jupiter vs Mars viewing...

[timboo]

Hi all! The last couple of nights we've had great viewing of Jupiter and it's four moons through our Celestron C8 with standard eyepiece - no barlows yet.

In the S/SW skies, there's the orangey-glowey star that I've assumed to be Mars, so last night swung the scope around to it... however... through the eyepiece, it still appears to be just a orangey-glowey star (forgive the terminology) so I was wonderiong, is it actually Mars? If it is, is it not going to be viewable without a barlow type lense? I thought that it would be at least as large as we're getting Jupiter (albeit pea sized through standard eyepiece) - what should my expectations be? :shrug:

Many thanks!

Tim

[RobF]

Probably antares you were looking at Tim?
Mars is tiny compared to Jupiter, but you should still be able to make out a small disk.

Jupiter is at opposition currently (as big as it gets this year) while mars and earth are way past closest distance currently too remember.....

[Roobi]

Hi there timboo. Have you checked out stellarium. Its a fantastic tool for beginners like you and i. Its a free download and you can view the sky and most of its objects from your area and at the time you wish. Its great for planning your night ahead. From melb mars and venus can be seen not long after sunset. Venus is the brightest and biggest you can see at dusk, mars is reasonably close, so you'll be able to look at both. I looked at venus last week through my 4mm and a barlow lens i borrowed, was pushing the magnification past the limits on my little scope, and it wasn't very clear, but the sheer size was a thrill. I can't wait till saturn shows its self again so i can try the barlow lense on that too.

But definatly try stellarium, its a great place to start finding things.

Happy hunting and i hope the weather stays clear.

cheers, Roobi

[pgc hunter]

Mars is nearing its frutherst point from Earth and as of Mid-late Sept it appears only 4" in diameter, just barely bigger than Uranus. It is also hopelessly low in the W after sunset so atmospheric turbulance with distort it.

I assume the "standard eyepiece" is the normal 25mm job, which in a 8" SCT gives about 80x, which is on the low side for planetary obs. With Mars at 4" diameter, it could well look like a star at that mag. And with it so low in the gunk near the horizon, you are not likely to see details. It's not your equipment or anything, Mars is well past its prime and unsuitable for observation at this time.

Mars never gets to Jupiter's angular diameter either, the best perihelic oppositions (such as 2003) bring it to 24-25", which is still half the size of Jupiter at opposition.



Cheers

[Roobi]

trust me to jinx myself, as soon as i said 'i hope the weather stays clear' dirty gray clouds decided to position themselves over me. Bugger. I was hoping to get out tonight... so much for that idea. :(

[Blue Skies]

You could have been looking at Antares. If that was the case then you would definitely have been seeing an 'orangey-glowey star". Stellarium or your star chart of choice should be able to clear that up for you. And as the other have said, Mars is around the far side of the sun at the moment and will look pretty small in the eyepiece. Best to wait until the next opposition in early 2012 for a decent look.

[timboo]

It was Antares - and oh WOW I love stellarium - this is some fantastic software, and free =] thank you all for your assistance. Tim.