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General Category => Everything Else => Topic started by: tuto99 on November 06, 2012, 02:03:38 PM

Title: Questions about my telescope
Post by: tuto99 on November 06, 2012, 02:03:38 PM
Even though I am familiar with astronomy, I never had the time to study telescopes, so I'm a huge novice(noob) at using these instruments. So I need your guys' help.
  My question is, could I be able to see Venus or Mars well with my telescope? I mean a decent size picture of it, not a small dot like with weaker telescopes. A few nights ago I saw Jupiter with my telescope, and it wasn't too huge, but I was satisfied and impressed.
  The lens I used to look at Jupiter that night was 25mm, and my telescope is about 2.5 feet. Do you think I'm able to view Mars or Venus?
Title: Re: Questions about my telescope
Post by: vh on November 06, 2012, 02:35:51 PM
Current geocentric distances in AU: (distance from earth)
Venus: 1.29 (radius 6050 km)
Mars: 2.07 (radius 3400km)
Jupiter: 4.16 (radius 69910km)
http://www.planetary-aspects.com/curr_asp/curr_posns.php (http://www.planetary-aspects.com/curr_asp/curr_posns.php)

radius / distance
Venus: 4690
Mars: 1643
Jupiter: 16805

keep in mind that this changes every day.

this seems to suggest jupiter would look ten times larger than mars and venus around 3 times larger than mars and 3 times smaller than jupiter.

HOWEVER*
this does not take account into the brightness of the objects.

you might be able to see Venus and Mars, but they might be so dim you won't notice them.

We can calculate the brightness of venus, mars, and jupiters, but because they orbit the sun like we do they have different phases like the moon and distances.

brightness comparison:
Mars: magnitude +1.23
Venus: magnitude -4.01
Jupiter: magnitude -2.67

this suggests that venus is twice as bright as jupiter and mars is 30 times dimmer than jupiter.

Title: Re: Questions about my telescope
Post by: tuto99 on November 06, 2012, 03:47:01 PM
So that means Venus will look smaller than Jupiter, and Mars will look smaller than Venus? That'll be a shame.
I already knew that depending on the phase of a celestial object, their absolute magnitude will vary. Thanks for the answers though. :)
Title: Re: Questions about my telescope
Post by: atomic7732 on November 06, 2012, 04:57:56 PM
my 6 SE has never been able to see mars better than a blob of red. Don't ever expect anything good. That way you won't be disappointed when the view sucks, but you'll be surprised when you actually can see something amazing.
Title: Re: Questions about my telescope
Post by: blotz on November 06, 2012, 04:59:19 PM
/me aims the hubble space telescope at mars.
/me thinks that view sucks, i cant expect anything good.
Title: Re: Questions about my telescope
Post by: tuto99 on November 06, 2012, 05:04:31 PM
my 6 SE has never been able to see mars better than a blob of red. Don't ever expect anything good. That way you won't be disappointed when the view sucks, but you'll be surprised when you actually can see something amazing.
I know. I was trying to say that I would be surprised if I was far from seeing Mars or Venus. But once again, I can't expect everything to be the way I wished it.
Title: Re: Questions about my telescope
Post by: atomic7732 on November 06, 2012, 05:35:08 PM
You'll be able to see them for sure, whether you get detail or not, that depends on a lot of factors.
Title: Re: Questions about my telescope
Post by: tuto99 on January 11, 2016, 04:40:09 PM
k thx luv appreshiate the feedback
sorry i forgot to post this 3 years ago
Title: Re: Questions about my telescope
Post by: DiamondMiner10 on January 11, 2016, 04:44:28 PM
did i just start a new era of bumping back very old threads
Title: Re: Questions about my telescope
Post by: atomic7732 on January 11, 2016, 04:47:33 PM
hopefully not