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07-12-2012, 13:02   #16
riffmongous
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You seem to be a man in the know. I don't really stargaze or anything like that, but I walk the dog every night so get a good chance to look at the stars. On a couple of really exceptionally clear nights recently, I've noticed what you describe - a faint fuzzy patch, which would be easy to mistake as a smudge on a lens if you wear wearing glasses.
It appear near Orion, roughly between 3 and 5 o'clock. Would this be a galaxy, or is it possible to see the faint traces of Nebulae with the naked eye?
The Pleiades cluster perhaps? If it is the Pleiades then its quite amusing since they are sometimes used as a standard of how good the seeing conditions are, so in your case they are pretty poor then.




the cluster is just above the moon in that picture

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07-12-2012, 13:32   #17
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A hundred years ago, before anyone knew what galaxies were, lots of things were classed as "nebulae" ... all the different fuzzy patches that clearly weren't individual stars. Many of these are star-forming regions within our own galaxy -- giant clouds of gas and dust lit up by newly formed stars within them. The Pleiaides are an example of this, so is the Great Nebula in Orion (the fuzzy patch in Orion's sword). Both are within some hundreds of light years of us. The Pleiaides are an open cluster -- new stars spreading out from the region where they were formed a hundred million years ago. The Orion nebula is even younger -- still in the process of blowing away the gas and dust from which new stars are forming.

The Pleiaides, the Orion nebula, and us, are actually all part of the same spiral arm of the galaxy. Stars form in the spiral arms of galaxies, and gradually drift away from them over time. That's why we can see spiral arms in galaxies. Although the majority of stars in a galaxy are small and old, the biggest and brightest (and therefore most visible) are also the ones that die the youngest, so they don't get to drift very far from where they were born in a spiral arm. Big stars are also bluer, so spiral arms will tend to look blue (even though the huge majority of stars are yellower, but less bright).



(This isn't really the Milky Way -- obviously we can't get outside to look back at ourselves)

Last edited by ps200306; 07-12-2012 at 13:34.
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07-12-2012, 16:14   #18
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This pair gets a good review, I have a simliar set and they are ideal for beginners...you'll need a tripod for them.

http://www.amazon.co.uk/Celestron-71...4876410&sr=8-1

These are what I use and are fine. Picked up a tripod cheap tripod yesterday in Aldi. Got my first look at the Andromeda galaxy earlier in the week
It makes you think about how small this island earth really is..
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07-12-2012, 16:17   #19
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I seen a program on the BBC, that if you where to travel at the speed of light it would take you 100 000 years to get from one side of our milky way to the other! and our milky way is one of millions.


The universe is big, really big!
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07-12-2012, 17:09   #20
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Are those red hyper giants in our Milky Way? Can they be seen with a telescope,
Yea they are all in the Milky Way. If you want to see one for yourself without a telescope then the most obvious choise is the star Betelgeuse. If you look above and slightly left of Orions belt you will see it. It's basically the shoulder of Orion the hunter. It's easily visible to the naked eye despite being over 600 light years away. If it were in our solar system in place of our sun, it is so big that it's surface would extend almost to Jupiter.

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You seem to be a man in the know. I don't really stargaze or anything like that, but I walk the dog every night so get a good chance to look at the stars. On a couple of really exceptionally clear nights recently, I've noticed what you describe - a faint fuzzy patch, which would be easy to mistake as a smudge on a lens if you wear wearing glasses.
It appear near Orion, roughly between 3 and 5 o'clock. Would this be a galaxy, or is it possible to see the faint traces of Nebulae with the naked eye?
As the other posters have said, this could be the Pleiades that you are looking at. The Pleiades is a star cluster and is also known as the seven sisters due to the 7 prominent stars that can be seen in the cluster with the naked eye, although the cluster actually contains many many more fainter stars which of course are visible with a telescope or binoculars. Actually if you look at the Pleiades through binouclars then you will be treated to one of the greatest sights in the night sky. Another open cluster near there is the Hyades which is below the Pleiades but still within the constallation Taurus. Well worth a look. If it's not the Pleiades you mean then it could be the Orion Nebula as another poster pointed out. The Orion Nebula, like all Nebulas, is a region of the sky where stars are formed from the dust and gases present there. It is located below Orions Belt in Orions Sword and again is a fantastic sight through binoculars and telescopes. The nebula appears to have a greenish hue to it when I look at it through my bincoulars. In reality the Nebula is a multitude of colours but the colours are not visible to the human eye as the colours are actually gases such as Hydrogen.

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Wow this is hurting my head, I thought I was looking at the visible Universe outside of the milky way and other galaxies.... Im not even looking outside the Milky way!!!!! Crikey , this puts a whole new dimension to things.... Thanks for all the Info
Not only are they all within the Milky Way but they are all very close to us realtive to the actual size of the Milky Way. Consider this, one of the furthest and most massive stars that you can see with the naked eye is the Garnet Star or to give it it's other name Mu Cephi. It's over 5000 light years away and is only visible to the naked eye due to its massive size. The Miky Way Galaxy is about 120,000 light years across so we are only seeing a small portion of our galaxy when we look up at night.

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I seen a program on the BBC, that if you where to travel at the speed of light it would take you 100 000 years to get from one side of our milky way to the other! and our milky way is one of millions.


The universe is big, really big!
I know, it boggles the mind doesnt it. Goes to show how massive the universe is when light can travel around the Earth 7 times in one second yet takes over 3 million years to reach our neighbouring galaxy, Andromeda, which is just one of many billions of galaxies out there. So when we look at Andromeda through our telescopes and binouclars we are seeing Andromeda as it appeared 3 million years ago. Similarly, if there were civilizations within Andromeda that had a telescope powerful enough to see into our galaxy and they found Earth, then they would be looking at Earth as it was 3 million years ago, so they wouldn't see the shaded side of the Earth lit up by city lights for example and the shapes of the continents would look far different too. It really is a mind-bender.
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09-12-2012, 23:54   #21
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I got a 130mm telescope last spring from Argos and have been hoping to be able to view Andromeda with it at some stage as its the only galaxy viewable to the naked eye in the Northern Hemisphere.
I dont think its viewable at the moment right?
When will we be able to see it and would it be viewable from the outskirts of a town like Drogheda?
I live in a housing estate on the edge of the town and I can see most stars on a dark night even with the street lights.

Just wondering also how it will appear in my telescope using a 20mm lens?

I can see the pleides easy (I always thought that was it) but I'm hoping that Andromeda will be viewable from the garden also.

How do you spot Andromeda with the eye even?
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10-12-2012, 01:22   #22
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The mind bender about traveling across the galaxy and back at near lightspeed is that the journey time to the other side and back is 200,000 years from the perspective of those on earth. To those on the ship, the trip would only take days or weeks. Time dialation is the phrase. Take a trip over to the andromeda galaxy and back might take a few weeks or months from your perspective but when you get back to earth, not only will everything and everyone you ever knew be long gone but there might be a different intelligent species waiting to greet you when you get home. The Homo Genus hadn't even split from the common ancestor we share with chimps 4 million years ago
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11-12-2012, 10:23   #23
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I got a 130mm telescope last spring from Argos and have been hoping to be able to view Andromeda with it at some stage as its the only galaxy viewable to the naked eye in the Northern Hemisphere.
I dont think its viewable at the moment right?
When will we be able to see it and would it be viewable from the outskirts of a town like Drogheda?
I live in a housing estate on the edge of the town and I can see most stars on a dark night even with the street lights.

Just wondering also how it will appear in my telescope using a 20mm lens?

I can see the pleides easy (I always thought that was it) but I'm hoping that Andromeda will be viewable from the garden also.

How do you spot Andromeda with the eye even?
Justin, Andromeda is viewable all year round. At the moment, it's at its highest about 8 in the evening, when it is almost overhead. So it's best seen at that time, or at least on the early side of midnight. It's not easy to spot with the naked eye unless you know exactly what you are looking for. If you have binoculars (and especially if you are having trouble finding it with the naked eye, which is often difficult or needs averted vision), they can help you find it before you try your telescope. Once you know where it is you will be able to find it again easily.

Start at Cassiopeia -- the W-shaped constellation that almost everyone knows how to spot. Think of the W as two V's stuck together and use the right hand V as an arrowhead. Stand facing south, which (if it's the early side of midnight) puts Cassiopeia a little behind you when you look straight up. The arrowhead is pointing almost straight at the Andromeda galaxy.

You may not see it though. What you should see, if you follow the arrowhead through the zenith and a little south of it, is a line of three stars in the Andromeda constellation -- Almaak, Mirach, and Alpheratz from left to right. (With good viewing you may see a faint fourth one between Mirach and Alpheratz). Alpheratz is also on the left corner of a very recognisable large square or diamond formation -- the Great Square of Pegasus. When you have your bearings come back to the centre star of the three in Andromeda, Mirach. Now look upwards slightly. You won't be able to see them with the naked eye but Mirach is itself the bottom of a line of three stars that you can see with binoculars. Very close to the top star of those three, there it is -- the Andromeda galaxy.

Once you've seen it, you may well find that its easy to spot with the naked eye in future. Just follow the arrowhead from Cassiopeia or go out from the Great Square of Pegasus.

Last edited by ps200306; 11-12-2012 at 10:28.
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11-12-2012, 23:33   #24
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Justin, Andromeda is viewable all year round. At the moment, it's at its highest about 8 in the evening, when it is almost overhead. So it's best seen at that time, or at least on the early side of midnight. It's not easy to spot with the naked eye unless you know exactly what you are looking for. If you have binoculars (and especially if you are having trouble finding it with the naked eye, which is often difficult or needs averted vision), they can help you find it before you try your telescope. Once you know where it is you will be able to find it again easily.

Start at Cassiopeia -- the W-shaped constellation that almost everyone knows how to spot. Think of the W as two V's stuck together and use the right hand V as an arrowhead. Stand facing south, which (if it's the early side of midnight) puts Cassiopeia a little behind you when you look straight up. The arrowhead is pointing almost straight at the Andromeda galaxy.

You may not see it though. What you should see, if you follow the arrowhead through the zenith and a little south of it, is a line of three stars in the Andromeda constellation -- Almaak, Mirach, and Alpheratz from left to right. (With good viewing you may see a faint fourth one between Mirach and Alpheratz). Alpheratz is also on the left corner of a very recognisable large square or diamond formation -- the Great Square of Pegasus. When you have your bearings come back to the centre star of the three in Andromeda, Mirach. Now look upwards slightly. You won't be able to see them with the naked eye but Mirach is itself the bottom of a line of three stars that you can see with binoculars. Very close to the top star of those three, there it is -- the Andromeda galaxy.

Once you've seen it, you may well find that its easy to spot with the naked eye in future. Just follow the arrowhead from Cassiopeia or go out from the Great Square of Pegasus.
Sound. Cloudy the last few nights and didnt think about it when we had a few clear nights the last few weeks
I was under the impression for years that the pleiades was Andromeda and only discovered my mistake two months ago when I took the telescope out. So I was a bit lost as to what I should be looking for with the naked eye when looking for the real Andromeda.
Will Andromeda be possible to see on a moonless clear night through telescope if I am living in a housing estate on edge of town? Its dark enough in the back garden and pleiades is clear to see with naked eye so hoping that Andromeda stands out also.
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12-12-2012, 05:43   #25
ps200306
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Sound. Cloudy the last few nights and didnt think about it when we had a few clear nights the last few weeks
I was under the impression for years that the pleiades was Andromeda and only discovered my mistake two months ago when I took the telescope out. So I was a bit lost as to what I should be looking for with the naked eye when looking for the real Andromeda.
Will Andromeda be possible to see on a moonless clear night through telescope if I am living in a housing estate on edge of town? Its dark enough in the back garden and pleiades is clear to see with naked eye so hoping that Andromeda stands out also.
"Officially", Andromeda is five times fainter than the Pleiades -- but it's hard to say what that practically means for quite different extended objects where the light is integrated across an area. However, it's not vastly different in apparent size from the Pleiades so yes, it's certainly a good deal fainter. You'll definitely be able to see it with your scope, but your problem will be getting it pointed in the right direction if you can't see it with the naked eye. I can't really say whether you'll be able to see it with the naked eye from your location -- best to just give it a shot, see what happens.

Btw, I used to think the Great Nebula in Orion's swords was Andromeda ... we live and learn.
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12-12-2012, 11:02   #26
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Justin, a good idea would be to locate it first with binoculars if you have a pair, otherwise, as ps200306 said, get a good idea of where to look using well known stars and then hunt it down using your lowest magnifaction eyepice, might be a 25mm....
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15-12-2012, 21:00   #27
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Justin, I went out and looked at the Orion nebula, Pleiades, and Andromeda through binoculars last night. Andromeda is very high overhead in the early part of the night. My nighttime eyesight isn't the greatest, but I have to say I could at best see the barest hint of Andromeda with the naked eye, whereas the Pleiades and Orion nebula were considerably brighter. Knowing where to look for it, though, I had no problem seeing it as a fuzzy patch through binoculars.
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16-12-2012, 15:39   #28
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I went out looking for it last night as I had friends down from Belfast.
Went out at 8pm and saw the W described in earlier post. Thought to myself, Grand I'll come back out in a while and be able to locate Andromeda. Went out at 11pm, then couldnt find the W again Think it might have diappeared behind house and couldnt be seen from garden. I couldnt spot any fuzzy patch for the life of me despite having new glasses during the week so my eyesight should be spot on. Some clouds started coming in after a half an hour of looking so had to abandon.

Anyway, I was happy enough to be able to show them Pleiades and Jupiter was clearest I've ever seen it ever last night. At maximum magnification 700x it appeared huge and the stripes were visible as well. Until last night it has always appeared as a ball of fuzz.

I know Andromeda should be easy to find. I'm just hopelessly unorganized.
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22-12-2012, 12:14   #29
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They are all stars within our own galaxy which is the Milky Way Galaxy. They are stars just like our sun but if you look closely some will appear orange in colour while others will be blueish or white. This difference in colour relates to how far along in it's lifecycle the star is. Our own star if viewed from space is actually white but appears orange when viewed from earth due to us having to look through our own atmospehere to see it. Also each star you see are of course different distances from us. Some are relatively close such as Sirius which is about 7 light years away and then there are others such as Deneb which are over 3000 light years away, so stars can vary vastly with regards their size and luminosity. The most luminous stars out there are tens of thousands of times brighter than our own sun, which is hard to get your head around. With regards size, some are so massive that our own sun would fit inside them millions of times over.
It's also worth pointing out that most planets are visible with the naked eye and also appear as stars. With the naked eye under good conditions you will see Mercury, Venus, Mars, Jupiter and Saturn but unless you know what you are looking at you will think they are stars. Download Stellarium to find them for youself.
As for other galaxies, they appear as faint fuzzy patches and you would not mistake them for other stars. That said, they aren't visible to the naked eye and you will need magnification to see them as they are so far away. The Andromeda galaxy is visible with binoculars and is around 3 million light years away. It is bigger than our own galaxy and contains more stars but due to how far away it is, it only appears as a fair fuzzy patch of light in the sky but well worth a look just because you know what it is and what it contains even if you can't see the details. Other galaxies are out there too but you need a telescope to see them and also need to know where in the sky to look. If you are currently viewing the sky with only your eyes, then invest in a pair of binoculars and you will be amazed at how much more you will see.
Can I ask a question?

If the Milky Way is 100,000 light years long at its longest points, and Andromeda is 3,000,000 light years away, then what's in between the Milky Way and Andromeda?

Just, empty space with no stars?
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22-12-2012, 14:16   #30
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Can I ask a question?

If the Milky Way is 100,000 light years long at its longest points, and Andromeda is 3,000,000 light years away, then what's in between the Milky Way and Andromeda?

Just, empty space with no stars?
Yes, pretty much empty space as far as we know. We and the Andromeda galaxy are part of a local group of about 30 galaxies, some of which have interacted gravitationally in the past. So it's possible that there are stars that have been flung out into intergalactic space in the same way that a planet or a spacecraft can get flung out of the solar system by an encounter with another planet. The black hole at the centre of a galaxy would be particularly efficient at flinging out stars.

So-called hypervelocity stars with speeds that would allow them to escape the Milky Way have been observed. Hypothetical stars wandering between the galaxies have been called "tramp stars". It would be extremely difficult to see them. By definition they would be dim stars because the biggest, brightest stars wouldn't live long enough to travel intergalactic distances. In principle, a star as dim as our own sun would be visible to the Hubble Space Telescope at the distance of the Andromeda Galaxy. But such intergalactic stars, if they exist, would be relatively few in number compared to the density of stars within the galaxies. So to a close approximation, the space between the galaxies is empty.

That said, there is also an extremely thin gas between the galaxies. It is about a million times less dense than the average gas inside the galaxies, in interstellar space. (And that interstellar gas is in turn ten million billion times less dense than air). But even the intergalactic gas between us and Andromeda is 200 times more dense than the most rarefied medium of all -- the gas that fills the intercluster voids between clusters of galaxies. There, there is about one atom for every cubic metre of space. That is as about as empty as the universe gets, anywhere.
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