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popeye85

I Thought They Said Jupiter Was Big?

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well ike everyone else I took advantage of the clear skies last night and headed out with the scope (skywatcher discovery 150mm) and was not disapointed-after having good views of orion plaides and sirius I turned my attention to the main star of the show ( no pun intnted-no really!), good old Jupiter. It was the first time I have had a chance to view this great planet and to be honest I'm not sure if was was in awe or disapointed! I could see the bands and 4 moons but I was shocked about how small it was in my scope-brley bigger than a large star-now I was not expecting it to fill the scope and certinly had no visions of seeing what the magazines publish but I wasn't expecting to have to strain as much I was to see this vast planet and was hopping for a slightly bigger disc!! never mind still had a great night and eagerly looking forward to getting back out there!

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What you saw is about right, you are never going to get a huge image of any of the planets at the eyepiece.

Have a look at this thread http://stargazerslounge.com/topic/196278-what-can-i-expect-to-see/ written by one of our very experienced observers for a good overview of what various objects look like at the eyepiece.

HTH and good luck.

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It's quite a nice view between 150x to 200x magnification - I like it at 180x where not too much atmosphere is magnified to ruin the view. But yes it's small and you need your scope set up right to get the clearest view. You get great contrast with a totally blackened ota - so a flocked newt, well baffled frac or cass with a decent dew shield all helps.

I find a long scope (1500mm to 2000mm) gets a sharper more detailed rendition than shorter focal lengths. And "learning to look" is probably the biggest contribution. Training the eye to scrutinise the detail found in a small view will reveal more features. It's a bit like looking at an amoeba in a microscope - a quick glance can be a disappointment - if you get my drift. :)

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Here's a very good link one of the mods (I think Stu?) posted a while ago: http://astronomer.wpengine.netdna-cdn.com/wp-content/uploads/2015/02/TAoS-2015_Month-1_SolarSystem.pdf

My own (limited) experience is to be patient, relax and look carefully. Different magnificent eyepieces bring out different detail, and experimenting with more/less can help. Recently (Nov-Jan roughly), Jupiter has been better after midnight and approaching the dawn. I saw a couple of nights ago before midnight, and it wasn't as good - just much too low the sky. That said, it's rising earlier each day, so it will be getting better as a late evening target.

Good luck!

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well ike everyone else I took advantage of the clear skies last night and headed out with the scope (skywatcher discovery 150mm) and was not disapointed-after having good views of orion plaides and sirius I turned my attention to the main star of the show ( no pun intnted-no really!), good old Jupiter. It was the first time I have had a chance to view this great planet and to be honest I'm not sure if was was in awe or disapointed! I could see the bands and 4 moons but I was shocked about how small it was in my scope-brley bigger than a large star-now I was not expecting it to fill the scope and certinly had no visions of seeing what the magazines publish but I wasn't expecting to have to strain as much I was to see this vast planet and was hopping for a slightly bigger disc!! never mind still had a great night and eagerly looking forward to getting back out there!

To misquote a famous comedy sketch, it's very big, but far, far away

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Popeye - I was looking at Jupiter this morning at x180 - which as others have said is a good magnification for this planet (a 4mm eyepiece in your scope) and it was a good size  and showed good detail.

Try looking at Mars for comparison - it's VERY small........

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Popeye - I was looking at Jupiter this morning at x180 - which as others have said is a good magnification for this planet (a 4mm eyepiece in your scope) and it was a good size  and showed good detail.

Try looking at Mars for comparison - it's VERY small........

Yeah - Jupiter and Saturn are most rewarding, and a decent size. Venus is nice too by virtue of its crescent feature. It's Mars that I found a let down.

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Mars varies enormously in apparent size depending on where it is in relation to the Earth. Presently it's a really tiny disk but at it's opposition in May 2016 it will appear as large as Saturn's disk.

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Popeye, keep  going back to Jupiter, it's always changing. Spend time watching and some nights you will be able to see the Great Red Spot as it crosses the disc. The 4 Galilean moons can be watched passing behind or in front (also their shadows) seen as black dots on the discs surface,  when conditions allow of course. 

L.

Edited by Lorne

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My avatar is an afocal snapshot of Jupiter taken through my 90mm f10 refractor at 91x, on an exceptional night, with a green planetary filter. There was no processing done, only cropping, and it is slightly less detailed than what was seen visually at the time. If you look closely though, you can see that there is actually quite a bit of detail visible, even at this low of a magnification.

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It's currently 720,000,000km away. That we can see it at all seems amazing to me!

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A magnification of 100x wiill make Jupiter much larger than the full Moon seen with the naked eye. Try looking at the full Moon through an empty tube and see how small the Moon then looks.

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The first time I saw Jupiter properly was at about 140x and I was quite gobsmacked. Unfortunately atmospheric conditions seem to affect Jupiter more than other planets and at times it can be quite blurry. I was luckier last night and even with only a 4" scope I got a decent 173x eventually. Even then, I had to observe for a while patiently. I often start off with only a 50x magnification at first to see what it looks like. It looked small but I could see surface detail. I think about 130x to 150x is about the lower limit for any real planetary detail. 

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Expectations need to be managed with astronomy, which is easy to say when you haven't looked at the object in question and don't know what to expect. Perspective helps here - I like to remind myself that I'm standing in my garden, under light polluted skies, and looking at things millions of light years away in some cases, with nothing more than a tube and a couple of mirrors. Suddenly everything is amazing again!

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A magnification of 100x wiill make Jupiter much larger than the full Moon seen with the naked eye. Try looking at the full Moon through an empty tube and see how small the Moon then looks.

Or if you can't wait until full Moon, drop a penny on the floor and look down at it from a distance of six feet. That's how big the full Moon looks with the naked eye, or Jupiter in a telescope at magnification x45. Does the Moon look big? Or the penny? Or Jupiter? They all have the same angular diameter, the rest goes on inside our heads. Learn to see Jupiter for what it is: not a penny, pea or photograph, but something very big and very far away. Try relaxing your eye to focus at infinity rather than close up, that might help. Or just use your imagination. Look for detail, not size. Even in a small telescope at relatively low magnification there can be a lot to see.

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Hi,as with any object the key thing is PATIENCE,patience and more patience......It takes a lot to see any detail on planets.DES

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...everything is amazing... !

Not sure I'll ever see a better summary of why stargazing is such a great pastime. I'm regularly dumbfounded by what's possible, but a lot of that amazement comes from appreciating what I'm looking at rather than the high definition widescreen technicolor spectacle.

For Jupiter, I can see swirling salmon and cream coloured clouds, extra-terrestrial storms bigger than the planet I live on, moons perceptibly moving in their orbits as I look, the planet itself visibly turning, shadows from moons cast onto the tops of the clouds, moons that could feasibly harbour alien life. And then I pop inside to make breakfast. It's genuinely mind blowing.

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Here's a pic I did a while ago to show the size of Jupiter through a scope. Just hold the screen at arm's length and it won't be too far away. x235 is the magnification most used on my C9.25, x260 and x300 are not usable on most nights due to seeing conditions.

Jupiter1.jpg

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mmmmm. I had it at 250X (although I did use a barlow to reach this) but certinaly wasn't near the image above-more like your image for 100x. but yes, to be able to see a storm that is ragging hunderds of millions of miles away is pretty mind boggling!

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mmmmm. I had it at 250X (although I did use a barlow to reach this) but certinaly wasn't near the image above-more like your image for 100x. but yes, to be able to see a storm that is ragging hunderds of millions of miles away is pretty mind boggling!

Assuming that the apparent field of view of the eyepiece / barlow was around 50 degrees, your true field at 250x would be .2 degrees or 720 arc seconds. Jupiter has an apparent diameter of around 41 arc seconds at the moment so it's disk will fit into this high powered field of view 17.5 times.

To illustrate that imagine a Table Tennis Ball in the centre of a circle 72 cm in diameter !

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Looking at it another way the 4 Galilean moons you saw have diameters are between 5,260km (Ganymede the largest) which is about as wide as the USA, and the smallest at 3,121km (Europa).  They are between 629 million Km and  928 million km away. Surely when you look at it like that then that is an amazing sight?.

In the grand scheme of things you will be in a very small minority of people to have seen those live and anything else you look at through your scope. Most people will never look up at night and see anything more than the stars and the moon.

Many years ago when I first saw Jupiter and it's moons through an old 4" refractor with diabolically dusty optics I was blown away with Jupiter and the red spot but I was more overcome with excitement at seeing the moons. I dragged my long suffering girlfriend out into the cold to show her...... She was completely underwhelmed as I had probably raised her expectations too high. Today when I look up with my scope I am always amazed even seeing the extra number of stars through the scope amazes me.

When you sit down and realise that in astronomy nothing is on the doorstep and that the distances you see things, apart from our moon, are in millions of miles, light years, millions of light years away then you realise that whatever you look up there is mind blowingly amazing.  Well that's how I feel when I look up.

A word of warning; when you move onto nebula don't expect big colourful clouds.

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Nebulas are probably one of the things I love most to look at- I reckon I spent about 2 hours looking at the Orion nebula the other night and enjoyed every minute of it. I feel that I must clarify that I was not disappointed when I saw Jupiter-l was still gobsmacked by seeing it  and got the same feeling of excitement I always do when I locate a new object in the sky-I was just surprised by how small it was in the e.p.  and if I had more time ( ok to be honest I was too cold to stay out any more) there is no doub I would have put in some serious study time to it!

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Here's a pic I did a while ago to show the size of Jupiter through a scope. Just hold the screen at arm's length and it won't be too far away. x235 is the magnification most used on my C9.25, x260 and x300 are not usable on most nights due to seeing conditions.

Jupiter1.jpg

What screen size? How far away should I hold my phone? Maybe I'll work it out for myself ;)

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