Andromeda Definition and 66 Threads

I asked a similar question on Quora not that long...

Hi all, I'm a bit nervous about the implications of relativity, not the block universe stuff I can work with that.. What worries me regards planes of simultaneity, when I'm walking away from you my plane of simultaneity will contain you from your past, so the you in my reference frame...

What happens first Sun Red Giant or Andromeda collision?

Hi If the universe is expanding, then why does the Andromeda Galaxy approach us? Does not it contradict Hubble's law?

Hi ! My question is the following: If there is a redshift in astronomical observations with other galaxies, as our Milky Way galaxy is approaching with the Andromeda galaxy, they must surely be in an accelerated approach due to the force of gravity between the two galaxies, and as our galaxy...

Has their been any explanations found for why the Andromeda galaxy is so much bigger in diameter than the MW, yet at the same time it's lighter? Is the Andromeda a type of Low-Surface Brightness (LSB) galaxy? Also maybe somewhat related, why is the Andromeda's central black hole so much...

Hi, I recently learned that if you can travel at the speed of light, or nearly, you can reach the Andromeda Galaxy within 30 years, due to time dilation and bypassing 2.5 million years on Earth. Is this true?

Hi, and thanks for reading. I asked this question in another forum too. If we agree that Andromeda is 2.5 million light years away, and its diameter around 220,000 light years, I don't see how it just appears as a regular point of light like any other star in the unaided eye. Something that so...

Hi Folks, I've read that by the time mankind is ready for intergalactic travel, our nearest galactic neighbour will be too far to even travel to. But I've also read that Andromeda is on a collision course with the Milky Way. Which is correct? And if the universe is expanding and everything is...

I do not understand how (in few bilion years) Milky Way and Andromeda will collide? If the universe is expanding and these objects which are far away have bigger speeds than those who are closer, than Milky Way and Andromeda will just be far away every moment... (?) Could someone help? :-)

https://en.m.wikipedia.org/wiki/Rietdijk%E2%80%93Putnam_argument Is the Andromeda Paradox accepted in physics? It seems to be based on the concept of relative simultaneity, but it seems quiet nonsensical. Wouldn't every observer seeing a different time period violate causality?

I understand that andromeda is blue shifted because it is moving towards us, but do we see any kind of redshift because of the expansion of the universe. Is andromeda less blue shifted than it should be because of cosmological redshift?

Do some scientists think that Andromeda won't collide with our galaxy?

Hi, I am new to this forum and I signed up because I am having difficulty working something out. I am no expert whatsoever when it comes to astrophysics so please be kind. We can measure the distance of galaxies using the speed of light, so we know that a galaxy 8 billion light years away for...

If everything in the universe is moving away from everything else in the universe, how can Andromeda collide in the distant future with the Milky Way?

Hi, this is my first post on here. Let's say I departure from Earth in a spaceship and reach a speed very close to c, as I go faster time would run slower and I would feel as if I was going faster and faster with no speed limit, even though I'm not going faster than c. Because my time is...

Dear PF Forum, Just out of curiosity :smile: Can we (through telescope or HST for example) see stars in Andromeda Galaxy? Is the Andromeda Galaxy the closes galaxy to us. Can we really be sure that there is no other galaxy across Milky Way because our line of sight is blocked by clusters of...

I've always read that the proof of the expanding universe is the red shift in all observable stars/galaxies showing velocity away from Earth observation. I've also read that the Andromeda galaxy is on a collision course with our galaxy. Would'nt that mean the stars in Andromeda would be green...

According to what I've read, the andromeda galaxy is approaching the milky way galaxy. Also, I've just recently discovered (on the net) that andromeda has a much larger subtended angle than the moon or sun. Hence, as it approaches it's angle subtended will keep increasing. I've also known that...

Using the Hubble Space Telescope, astronomers have discovered that the immense halo of gas enveloping the Andromeda galaxy is about six times larger and 1,000 times more massive than previously thought. http://scitechdaily.com/halo-around-the-andromeda-galaxy-is-larger-than-previously-thought/...

I just recently got a dobsonian reflector telescope, (Orion SkyQuest XT8 PLUS Dobsonian Reflector Telescope) and I was wondering what the best way to see the andromeda galaxy would be using the telescope? Of these, which would be the best eye piece for that sort of thing?: Orion 2" 28mm...

Homework Statement This is from chapter 1 (2nd edition) of Taylor and Wheeler's 'Spacetime Physics.' It's a four part problem, and I didn't have any troubles with parts a, b, or c. I'm stuck on part d. I'm supposed to determine if we could make it to Andromeda within a lifetime. Assume that...

Article: https://en.wikipedia.org/wiki/Rietdijk–Putnam_argument

As many are aware, the announced detection of primordial gravity waves by BICEP 2 was heavily criticized based on dust emission modeling. Today, Planck XXV was released which mapped out the dust emissions of Andromeda. Assuming Andromeda is representative of the Milky Way in most relevant ways...

Suppose I have a spaceship that can accelerate to c in one month of acceleration/deceleration of month and I want to travel to Andromeda. From my frame of reference wouldn't my total travel time be two months?

Tonight was an amazing night for stargazing so I drove about 10 minutes to a nice countryside road with barely any lights. It was really dark, and you could see a faint glow of the milky way. I had some apps to help me locate various galaxies and etc. and I wanted to see Andromeda but I...

Can somebody explain the implications of the well known Andromeda paradox in a metaphysical sense? First, does it state that all events are determined? If one observer already knows what happens on the Andromeda galaxy, could it be possible that that event still happened in an indeterministic...

Homework Statement A traveller with mass m = 66,5 kg travels with a velocity of 0,82 c to the Andromeda galaxy which is a distance of 2,55·106 lightyears away. Light with the wavelength 459,4 nm is emitted from the galaxy. assume the galaxy doesn't move and use the exact speed of light. How...

If the galaxies are moving away from each other.

Since black-holes are the catalyst of galaxies and black-holes nomnomnom galaxies; wouldn't it be true that the Milkyway galaxy is shrinking, taking Earth (our solar-system) with it, NOT the holamola entire universe expanding? So, wouldn't the Milkyway galaxy implode before it would collide...

where is andromeda? I know that when i look at the andromeda galaxy i am seeing it as it was 2.5 million yrs ago. what i want to know is am i seeing it where it is physically in space now or has it moved closer to us in the 2.5 million yrs that the light has taken to reach us...

"A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy" Published in Nature 3 days ago. Rodrigo A. Ibata, Geraint F. Lewis, Anthony R. Conn, Michael J. Irwin, Alan W. McConnachie, Scott C. Chapman, Michelle L. Collins, Mark Fardal, Annette M. N. Ferguson, Neil G...

I have calculated the wavelength of a line that would be observed in a spectrum from Andromeda where speed and λ0 were known, using the formula z =∆λ/λ0 and z=v/c. I obtained a value smaller than λ0 because Andromeda display a blue shift. After I calculated the same wavelength pretending that...

Homework Statement We are not allowed to use any videos from youtube. They have to be a realiable source. We are having difficulty copying the embeded link to the power point presentation. Homework Equations The Attempt at a Solution First, we right click on the video to copy it...

The frequency of supernovas in our galaxy is about one per century. Has there been a supernova in the Andromeda Galaxy in the last 200 years?

A HST team measure the sideways motion of Andromeda so they can be definite about the collision.Here is a movie. http://hubblesite.org/newscenter/archive/releases/2012/20/video/a/ Here are the technical papers that the movie and press releases are based on: http://arxiv.org/abs/1205.6865 The...

If an observer on the Andromeda galaxy looked back at us, how would the Milky Way galaxy look to him? Edge-on, spiral face on, or in between?

Two thoughts on this. If the Milky Way is one hundred light years in diameter and Andromeda is 2.5 million light years away that means Andromeda is 25 times the diameter of the Milky Way distant from us. That's not much. When will they merge? And I wonder how long it will take for the...

Hi... Just wondering... Will the Andromeda galaxy really collide with the Milky Way in 3-5 billion years? I've seen a supercomputer-generated video, but is there any actual proof other than the theories of various scientists? Even though it was NASA who came up with it...

Excuse my ignorance. I don't know much about this subject, but there's something I've read about that I don't understand. If space is expanding and everything is getting further away from everything else, how is Andromeda heading towards us?

I was recently asked a few questions about these galaxies. As I was by no means sure of my responses (apart from the last :biggrin: ) I am posting the questions and answers in the hope that someone will either confirm or better them. In an expanding Universe, why are Andromeda and the Milky...

i just realized, Andromeda paradox is flawed. I feel good, as compared with penrose, I am really just started in this subject. it is flawed becuase penrose mistakendly consider the"each day" for the person in moving (although very slow) and the person are the same. They are not same. the...

hi, if i travels at 0.99999c, i will measure time between andromeda and I (events happens in andromeda) shrink to only 0.00447 x 2 millions yrs compared with a person in rest on earth? Is this right, from t' = t x (1-v^2/c^2)^0.5 So if i travels to 0.99999999999999999999...c, then i can see...

Hello, Can someone explain the http://demonstrations.wolfram.com/TheAndromedaParadox/" ? What does it mean, philosophically/etc? Local and non-local events. Time? Was this paradox an invitation for an explanation of the unknown concept at the time called "spooky action at a distance"? Which we...

What features of Andromeda Galaxy can you make out with an Amateur Telescope?? With an amateur telescope, (field of view of 2 degrees) what features can see you see in and around the andromeda galaxy? Just curious.

I am doing a project on Andromeda, just doing a big write up about it, and draw some pictures of it by hand and so on. Anyone have some facts on it that may not be so well known, and maybe some interesting facts about it that the average stargazer might not know that I can write about. ...

Can we "use" the Andromeda Paradox? Perhaps the term I should be using is "relativity of simultaneity"... anyway :) Usually I see the Andromeda Paradox stated in terms of a stationary observer and another who is moving toward the galaxy. I did find one source that said the reverse effect...

Homework Statement Paraphrase: A Transporter can reduce a person to data and transmits the data by light or radio signal to another location. A person is beamed from Earth to the planet Zircon orbiting a star in the Andromeda Nebula, two million light-years from Earth. Neglect any relative...

So it's often said that the Andromeda galaxy is much wider than the moon, if you count all of its outer regions as well. Yet, you can clearly see much of the Andromeda's spiral structure in the small region that the visible-to-naked-eye region occupies. So what do the outer regions of it look...

I read that Andromeda galaxy is moving towards our galaxy at a speed of 200,000 miles per hour. Does it mean that Andromeda galaxy has increased mass and slowed time in comparison to us (or the opposite is true or no effect on its mass or time is there)? No mathematical answers please (I am...