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Any astronomy buffs about tongiht (29thAug) ?

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Any astronomy buffs about tongiht (29thAug) ?

A very large bright object up in the South/South East (can't find my compass)  about 23:00z.
I'm presuming it's Jupiter, and I can also see two bright slightly coloured objects just to the right (from observer's POV).
Wondered if these are Galilean moons? Or just coincident stars behind?
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VileReynard
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Re: Any astronomy buffs about tongiht (29thAug) ?

Quote
All four Galilean moons are bright enough that they could, if they were farther away from Jupiter, be sighted from Earth without a telescope. They have apparent magnitudes between 4.6 and 5.6 when Jupiter is in opposition with the Sun,[33]  and are about one unit of magnitude dimmer when Jupiter is in conjunction. The main difficulty in observing the moons from Earth is their proximity to Jupiter since they are obscured by its brightness. The maximum angular separations of the moons are between 2 and 10 minutes of arc from Jupiter,[34]  close to the limit of human visual acuity. Ganymede and Callisto, at their maximum separation, are the likeliest targets for potential naked-eye observation. The easiest way to observe them is to cover Jupiter with an object, for example, atree limb or a power line that is perpendicular to the plane of moons' orbits.

See http://www.newworldencyclopedia.org/entry/Galilean_moons
So it's likely that you didn't see the moons.

avalon
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Re: Any astronomy buffs about tongiht (29thAug) ?

I wonder if it was the International Space Station you saw?  It's apparently visible from earth, from the map I just looked at it seems it'd be passing over just off the South East Coast of the UK sometime around 22.30-23.00 last night.
pierre_pierre
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Re: Any astronomy buffs about tongiht (29thAug) ?

last nights sky map below.  yes was probably Jupiter
Out of interest we have an Astronomy nutter in South Essex, comes on the Local radio to talk about his interest in a peculiar voice, this morning it was they have found another set of planets around a star, only to be seen if you have the worlds largest telescope.
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Re: Any astronomy buffs about tongiht (29thAug) ?

Over the years there have been numerous reports of being able to see Jupiter's moons (the 4 brightest) with the naked-eye. The seeing conditions would have to be pretty well perfect ie.moon-less (which last night wasn't) you would probably need to be viewing over a large expanse of water to eliminate light pollution from cities, town's street lights etc. and a very dark sky. And you would need very good vision.
They are though a very easy view with even moderate power binoculars, providing you can keep them still (braced or tripod) But remember, that its a moving planet you're looking at, and will appear to move across your field of view quite quickly. How do you know you've seen them? try and look two nights running or at least a couple of hours later and the moons will have changed position.
Experience; is something you gain, just after you needed it most.

When faced with two choices, simply toss a coin. It works not because it settles the question for you. But because in that brief moment while the coin is in the air. You suddenly know what you are hoping for.
pierre_pierre
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Re: Any astronomy buffs about tongiht (29thAug) ?

according to my program there was only one Jupiter moon in view, diagonally opposite to our moon - Callisto and that was very dim so probably need a good telescope to see it, but earlier all four moons were in view, as was Uranus
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Re: Any astronomy buffs about tongiht (29thAug) ?

thanks all
@Petlew -- I neglected to say that I was using a pair of good 8x42 bins rather than just naked eye.
@me - Certainly wasn't the ISS -  it moves!
pierre_pierre
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Re: Any astronomy buffs about tongiht (29thAug) ?

the two in my pic above are closest  Io and Ganymede, Calisto is just to the top of Jupiter as a bump and Europa is just beside Io on the surface of Jupiter
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Re: Any astronomy buffs about tongiht (29thAug) ?

Well, as an aside, although I haven't looked for it, I understand that Saturn's rings are at a good viewing angle at this time, if you know where and when to find it. More reports say they can be seen with good binoculars and good conditions. In my youth I had use of a 4" retractor telescope and could easily see them with that...fascinating!!
If you can still get it, there is an essential book by Patrick Moore titled "Naked Eye Astronomy" very informative and easily readable in PM's usual way. It is however quite old now, but you might find copies available if you Google it. My copy is yellowed with age!!
Edit: Amazon does indeed have a few copies of the book (all used copies) for as little as £4.12 Get it while you can!!
http://www.amazon.co.uk/Naked-Eye-Astronomy-Patrick-Moore/dp/0718805968
Experience; is something you gain, just after you needed it most.

When faced with two choices, simply toss a coin. It works not because it settles the question for you. But because in that brief moment while the coin is in the air. You suddenly know what you are hoping for.
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Re: Any astronomy buffs about tongiht (29thAug) ?

excellent stuff ... but my hobbies are costing me quite enough at the moment without getting drawn into a "my-life-can-only-be-improved-by-buying-an-astro-telescope" obsession!
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Re: Any astronomy buffs about tongiht (29thAug) ?

Ah! but you don't need one to enjoy the night sky, just a dark night, a comfy chair (no light pollution if possible) and a minimum of knowledge to find your way around...very therapeutic.
Only downside is the better viewing nights -dark, things to look at, still air etc.- are mostly on view in the depths of winter (Orion in its full glory almost overhead once seen will never been forgotten) so a flask of soup and a thick coat would be a good idea. The summer stars (in the northern hemisphere anyway) are not as interesting as the winter constellations and since it never gets really dark, a rather duller place to be (although warmer)
Ok so I'm an old fashioned romantic...
Experience; is something you gain, just after you needed it most.

When faced with two choices, simply toss a coin. It works not because it settles the question for you. But because in that brief moment while the coin is in the air. You suddenly know what you are hoping for.
Community Veteran
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Re: Any astronomy buffs about tongiht (29thAug) ?

as a child i was terribly into it all and while I didn't have a scope or bins, did have a lovely astro map ... simply hadn't noticed Jupiter so big and bright before.
Luckily enough I'm in a fairly rural location so light pollution is not too bad and I generally make time to look up ... Though it doesn't compare to being on the middle of Lake Titicaca and being able to see the Milky Way in all it's density (I can't remember the last time I was able to see it from the UK)
pierre_pierre
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Re: Any astronomy buffs about tongiht (29thAug) ?

Saturn at this moment is mid sky to the SSE, unfortunately it is below the horizon at night
if you look WSW just before sunset tonight, Venus will just be above the horizon, due W at the same altitude going down will be saturn
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Re: Any astronomy buffs about tongiht (29thAug) ?

Quote from: paulh
Milky Way in all it's density (I can't remember the last time I was able to see it from the UK)

As it happens I was recently in a moonless, dark part of the New Forest in time for the Perseid meteor shower, and at 01:00 on the 17th Aug the Milky Way was as clear as I've seen it from the UK for many years. Not normally a summer object to view as light pollution or light whispy cloud will normally hide it. Sorry to keep going on about light pollution, but its one of the great modern restrictions to successful terrestrial astronomy, and the reason most modern major terrestrial telescopes are or are being built on mountain tops, often above the cloud line.
Experience; is something you gain, just after you needed it most.

When faced with two choices, simply toss a coin. It works not because it settles the question for you. But because in that brief moment while the coin is in the air. You suddenly know what you are hoping for.
pierre_pierre
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Posts: 19,757
Registered: 30-07-2007

Re: Any astronomy buffs about tongiht (29thAug) ?

there is a free mini sky chart from the makers of the one I have here http://www.starrynighteducation.com/skychart/#Req=4&LatD=43&LatM=40&LatRG=N&LonD=79&LonM=24&LonRG=W&...