one very bright object + 2 smaller bright object at its side

joshuatj · Post by **joshuatj** » Tue Sep 08, 2009 11:18 pm

Hi everyone,
I'm new here.
I'm new to Astronomy too.
I just got myself a Celestron Firstscope from Amazon.com

I just got the telescope today and I just came back from my first attempt @ star-gazing.
It was very cloudy tonight but I've managed to find a bright spot (south sky) and tried focussing on it.
After some time, we've managed to get the bright object on focus.
We see one very bright object + 2 smaller bright object at its side.
We're wondering what it is that we saw, anyone?

Post by **Airconvent** » Tue Sep 08, 2009 11:28 pm

You sure its South? If its in E-W orientation, then likely its Jupiter. Can you see the disk with colour bands? If yes, then the 2 would likely be the Galilean moons. There should be up to 4 visible depending on their position at time of obbing.
btw, welcome to Singastro! [smilie=cute.gif]

joshuatj · Post by **joshuatj** » Tue Sep 08, 2009 11:30 pm

E-W, you mean the stars' alignment? Ya, it's E-W.
But I only see two, maybe my telescope's resolution is not high enough.

Post by **Airconvent** » Tue Sep 08, 2009 11:44 pm

Hi
I meant the object rise from the East and set in the west. Jupiter is near zenith at 10.30pm presently (i.e. overhead). Even the lowest power telescope will be able to see up to 4 moons (Galileo did with his crude scope). But if the moon has gone in front or behind the planet, then you will not see it but they move very quickly so within an hour they should reappear.

joshuatj · Post by **joshuatj** » Tue Sep 08, 2009 11:59 pm

ooo.... moving, yes, they move from East to West.
Hmm... maybe the moon really did went behind Jupiter.

My friend said he saw that the brighter spots are elongated, maybe it was the moons.

Post by **Airconvent** » Wed Sep 09, 2009 12:05 am

joshuatj wrote:ooo.... moving, yes, they move from East to West.
Hmm... maybe the moon really did went behind Jupiter.

My friend said he saw that the brighter spots are elongated, maybe it was the moons.

elongated is caused by less than perfect optics in your refractor.... [smilie=admire.gif]

joshuatj · Post by **joshuatj** » Wed Sep 09, 2009 12:09 am

i see.. now too cloudy can't see it anymore.
BTW, Stellarium is awesome!

brandon.chia · Post by **brandon.chia** » Wed Sep 09, 2009 4:13 pm

Yesterday, Lo, the moon. Was in front of jupiter

joshuatj · Post by **joshuatj** » Wed Sep 09, 2009 5:01 pm

I thought it's supposed to be IO instead of LO?

joshuatj · Post by **joshuatj** » Thu Sep 10, 2009 2:51 am

we tried gazing tonight again.
We saw Jupiter with 3 moons. Apparently Ganymede and Europa overlapped each other today (according to Stellarium).

Then we saw another two bright spot 45 degrees apart (still at SW sky), to the left of Jupiter. We have no idea which star is it, I suspect it's alpha Gru and beta Gru?
How do i know for sure which object I'm seeing?