# Are there stars in intergalactic space? **URL:** \ **Category:** Factual Questions\ **Created:** [March 31, 2009, 11:28am UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408 "2009-03-31T11:28:11Z")\ **Posts on this page:** 20\ **Page:** 4
**Author:** ![ivan\_astikov](https://avatars.discourse-cdn.com/v4/letter/i/58f4c7/32.png) [@ivan\_astikov](https://boards.straightdope.com/u/ivan_astikov)\ **Post date:** [April 6, 2009, 9:29pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/61 "2009-04-06T21:29:36Z")
> [@Squink](#): > > This is incorrect. Pray tell me more! ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [April 6, 2009, 10:14pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/62 "2009-04-06T22:14:02Z")
> [@ivan\_astikov](#): > > Pray tell me more! It’s been a few years, and refs have disappeared. Meanwhile, Wikipedia isn’t so good on [false vacuums](http://en.wikipedia.org/wiki/False_vacuum) and [inflation](http://en.wikipedia.org/wiki/Inflation_(cosmology)). However, Guth’s 1991 article [Can a Man-Made Universe Be Achieved by Quantum Tunneling Without an Intial Singularity](http://www.nap.edu/openbook.php?record_id=1851&page=153), contains the relevent point in its abstract: > [@](#): > > Essentially all modern particle theories suggest the possible existence of a false vacuum state - a metastable state with an energy density that cannot be lowered except by means of a very slow transition. Inflationary cosmology, which is briefly reviewed, makes use of such a state to drive the expansion of the big bang, allowing the entire observed universe to evolve from an initial mass of only about 10 kilograms. … 10 kilograms is considerably less than all the matter currently in the universe. The rest of the matter/energy that’s around today appears as the false vacuum decays and space expands. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 6, 2009, 10:15pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/63 "2009-04-06T22:15:54Z")
> [@](#): > > Pray tell me more! The biggest problem with what you said is that the Big Bang didn’t occur at _a_ point; it occurred at _every_ point. Every point in the Universe has an equal claim to be the center. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [April 6, 2009, 10:18pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/64 "2009-04-06T22:18:55Z")
> [@Chronos](#): > > Every point in the Universe has an equal claim to be the center. :rolleyes: It really is all about you, isn’t it, **Chronos**? 😉 ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [April 7, 2009, 2:26am UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/65 "2009-04-07T02:26:49Z")
> [@Chronos](#): > > This appears to be the case, but it’s a consequence of the particular conditions of the Universe, not the way the physics operates. A decade ago, it was not known whether gravity would cause the balloon to collapse eventually or not. Imagine there were enough mass to pull the whole thing together again, would the balloon collapse or would all the dots collect at some point on the surface of the balloon? Or would the aggregation of the dots make the balloon collapse? Would enough mass just concentrate all the mass and leave space empty or would space itself shrink? ---
**Author:** ![ivan\_astikov](https://avatars.discourse-cdn.com/v4/letter/i/58f4c7/32.png) [@ivan\_astikov](https://boards.straightdope.com/u/ivan_astikov)\ **Post date:** [April 12, 2009, 11:42am UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/66 "2009-04-12T11:42:49Z")
> [@Chronos](#): > > The biggest problem with what you said is that the Big Bang didn’t occur at _a_ point; it occurred at _every_ point. Every point in the Universe has an equal claim to be the center. This doesn’t make sense! Galaxies are moving through space. If we look at them from a relatively fixed perspective, ie Earth, are they criss-crossing the heavens in random directions, or do their paths extrapolate backwards to a fixed point? It doesn’t sound as if you are suggesting the latter, and if that is the case, I’ll have to admit I had totally misunderstood the concept of the “Big Bang”. ---
**Author:** ![CC](https://avatars.discourse-cdn.com/v4/letter/c/f1d935/32.png) [@CC](https://boards.straightdope.com/u/CC)\ **Post date:** [April 12, 2009, 5:54pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/67 "2009-04-12T17:54:58Z")
> [@psychonaut](#): > > Well, to be fair, its apparent size in the sky is many times that of the moon. Here is [the Andromeda Galaxy and the Moon in collage](http://www.nhn.ou.edu/%7Ejeffery/astro/astlec/lecture.html) showing their relative sizes. The moon appears only about half a degree in diameter. Ok, I’m stuck on this. Before looking at that link, I used to believe that I had seen - on a very dark night - a tiny smudge that I took to be the Andromeda Galaxy. At least, it was where I was led to believe I should look if I wanted to see it, with binoculars. Now, if I correctly interpret this graphic, it turns out that the galaxy is considerably wider than the moon??? Can someone help me make sense of this? ---
**Author:** ![Nicest\_of\_the\_Damned](https://avatars.discourse-cdn.com/v4/letter/n/8baadc/32.png) [@Nicest\_of\_the\_Damned](https://boards.straightdope.com/u/Nicest_of_the_Damned)\ **Post date:** [April 12, 2009, 7:13pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/68 "2009-04-12T19:13:57Z")
If wikipedia can be believed: > [@](#): > > …It appears quite small without a telescope because only the central part is bright enough to be visible, but the full angular diameter of the galaxy is seven times that of the full Moon. > **[Andromeda Galaxy](https://en.wikipedia.org/wiki/Andromeda_Galaxy)** > > The Andromeda Galaxy is a barred spiral galaxy\[c\] and is the nearest major galaxy to the Milky Way. It was originally named the Andromeda Nebula and is cataloged as Messier 31, M31, and NGC 224. Andromeda has a D25 isophotal diameter of about 46.56 kiloparsecs (152,000 light-years) and is approximately 765 kpc (2.5 million light-years) from Earth. The galaxy's name stems from the area of Earth's sky in which it appears, the constellation of Andromeda, which itself is named after the princess w... According to this site, it will fill the eyepiece of most telescopes. [http://www.allaboutastro.com/M31.html](http://www.allaboutastro.com/M31.html) ---
**Author:** ![WoodenTaco](https://avatars.discourse-cdn.com/v4/letter/w/45deac/32.png) [@WoodenTaco](https://boards.straightdope.com/u/WoodenTaco)\ **Post date:** [April 12, 2009, 7:43pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/69 "2009-04-12T19:43:21Z")
> [@ivan\_astikov](#): > > This doesn’t make sense! Galaxies are moving through space. If we look at them from a relatively fixed perspective, ie Earth, are they criss-crossing the heavens in random directions, or do their paths extrapolate backwards to a fixed point? > > It doesn’t sound as if you are suggesting the latter, and if that is the case, I’ll have to admit I had totally misunderstood the concept of the “Big Bang”. All points are receding from us at velocities directly based on their distance. If we did that extrapolation, we’d find that the big bang occurred on Earth. While possible, it is far more likely that there was just an expansion of space itself; in other words, if you performed that extrapolation from _anywhere_ you’d get the same result and find that you were at the center. Another way to look at it is this: the Big Bang’s “position” is just t=0, the beginning of time. If we use a telescope to observe very distant objects, we are looking back in time since the light takes so long to get here. If we look far enough away, we can be looking 14 billion years in the past, that is, we can look at the big bang. Where do we have to point our telescope to find this? Anywhere. Since everything originated with the bang, we can find t=0 everywhere in the sky as an expanding sphere, with a distance equal to the age on the universe in light years. ---
**Author:** ![WoodenTaco](https://avatars.discourse-cdn.com/v4/letter/w/45deac/32.png) [@WoodenTaco](https://boards.straightdope.com/u/WoodenTaco)\ **Post date:** [April 12, 2009, 7:47pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/70 "2009-04-12T19:47:49Z")
Footnote: we can’t actually observe the bang itself due to some highly technical properties of the early universe. But we can come extremely close - the theoretical limit is 10^-43 seconds. The closest we have come as of now is observations of the cosmic microwave background radiation with WMAP. ---
**Author:** ![CC](https://avatars.discourse-cdn.com/v4/letter/c/f1d935/32.png) [@CC](https://boards.straightdope.com/u/CC)\ **Post date:** [April 12, 2009, 8:45pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/71 "2009-04-12T20:45:34Z")
> [@Nicest\_of\_the\_Damned](#): > > If wikipedia can be believed: > > According to this site, it will fill the eyepiece of most telescopes. This is just mind boggling. There is, in the sky, an “object” that is 6 times wider than the moon, and it’s a galaxy that’s 2+ million light years away. And it’s that big! I’m totally freaked by the notion. The scale and proportion of things has suddenly been shifted for me. I gotta think about this. ---
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [April 12, 2009, 9:39pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/72 "2009-04-12T21:39:22Z")
> [@CC](#): > > This is just mind boggling. There is, in the sky, an “object” that is 6 times wider than the moon, and it’s a galaxy that’s 2+ million light years away. And it’s that big! I’m totally freaked by the notion. The scale and proportion of things has suddenly been shifted for me. I gotta think about this. I had a similar thought when read that in this thread. However, what really boggles my mind is that I’ve never noticed it. I even did a little amateur astronomy in my youth, but mostly looked at things in our solar system. You really realize how much we lose by having all these blasted lights in our cities. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 13, 2009, 2:12am UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/73 "2009-04-13T02:12:32Z")
> [@](#): > > The closest we have come as of now is observations of the cosmic microwave background radiation with WMAP. To expand on this: The light we see in the CMB was emitted about 300,000 years after the Big Bang. A cosmological neutrino detector could push that back to around 200,000 years after the Bang. A gravitational wave observatory, however, could in principle look back to around 10[sup]-32[/sup] seconds after the Bang. It’d take an instrument several generations more advanced than anything we have right now, but it could be done. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [April 14, 2009, 6:51am UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/74 "2009-04-14T06:51:14Z")
> [@Chronos](#): > > To expand on this: The light we see in the CMB was emitted about 300,000 years after the Big Bang. A cosmological neutrino detector could push that back to around 200,000 years after the Bang. A gravitational wave observatory, however, could in principle look back to around 10[sup]-32[/sup] seconds after the Bang. It’d take an instrument several generations more advanced than anything we have right now, but it could be done. What we’re going to get in the meantime is [Planck](http://en.wikipedia.org/wiki/Planck_(spacecraft)), a spacebourne observatory which will look at polarization in the CMB. Said polarization may have been caused by those graviational waves. There’s an article in the May 2009 Sky&Telescope about it, but it doesn’t seem to be available on the S&T web site. ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [April 14, 2009, 1:11pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/75 "2009-04-14T13:11:01Z")
Could someone help an ignorant here finding Andromeda. My location can be dark enough at some times (We are about to enter blackout season) and I would love to see that. Can it be seen with the naked eye?. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [April 14, 2009, 1:41pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/76 "2009-04-14T13:41:00Z")
> [@Sapo](#): > > Could someone help an ignorant here finding Andromeda. My location can be dark enough at some times (We are about to enter blackout season) and I would love to see that. Can it be seen with the naked eye?. Yes, but is BEST seen with low power binoculars generally. Run of the mill 7X by 50’s are about perfect. Even then, its nothing spectacular. The WOW factor (as in most visual astronomy) comes more from realizing what you are looking at rather than said thing looking like something from a modern Sci Fi movie. What part of the world do you live in? And how far away from/in how big a city are you? ---
**Author:** ![ivan\_astikov](https://avatars.discourse-cdn.com/v4/letter/i/58f4c7/32.png) [@ivan\_astikov](https://boards.straightdope.com/u/ivan_astikov)\ **Post date:** [April 14, 2009, 1:42pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/77 "2009-04-14T13:42:39Z")
I’ve just been reading the bit in the wikipedia link about the Andromeda galaxy and blue shift, and was wondering whether if someone who was observing our galaxy from within Andromeda would see a red or blue shifting galaxy? If we are both blue shifting relative to each other, does this suggest a future cataclysmic collision? Is it possible that the Andromeda galaxy is moving towards us but because we are moving away it will never catch up to us? How would we be able to determine this? ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [April 14, 2009, 1:57pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/78 "2009-04-14T13:57:15Z")
> [@billfish678](#): > > Yes, but is BEST seen with low power binoculars generally. Run of the mill 7X by 50’s are about perfect. > > Even then, its nothing spectacular. The WOW factor (as in most visual astronomy) comes more from realizing what you are looking at rather than said thing looking like something from a modern Sci Fi movie. > > What part of the world do you live in? And how far away from/in how big a city are you? I am in Puerto Rico, in a very small town but still some light pollution. Although as I said, summertime is blackout season so I do get plenty of opportunities to look at the sky surrounded by pure darkness. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [April 14, 2009, 2:40pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/79 "2009-04-14T14:40:30Z")
> [@Sapo](#): > > finding Andromeda… Find Cassiopia by looking for a big W in the sky up to the north. The W is comprised of two triangles, the sharper of the two, on the right, points almost directly at the galaxy in Andromeda. The galaxy is shown as M31 on this chart: > **[The Constellation Cassiopia - by Astronomy Net](http://www.astronomy.net/constellations/cassiopia.html)** > > The Constellation Cassiopia - by Astronomy Net ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [April 14, 2009, 4:24pm UTC](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408/80 "2009-04-14T16:24:36Z")
So for this time of year, better by dawn looking north-east, right? [Previous page](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408.md?page=3) [Next page](https://boards.straightdope.com/t/are-there-stars-in-intergalactic-space/491408.md?page=5)