In what direction is the universe expanding?

[The Silverdale Phantom]

Mosaic of the Large Magellanic Cloud.


Cheers!

 

[Dark Corner]

What ever happened to 31/Atlas as load of stuff all over the net last year then nothing from December onwards ?

 

[Nuke]

It's moving further away now. December was its closest point to Earth, which even that wasn't particularly close, and it's now continuing on its merry way. Ne'er to return.

 

[Fangs]

Unrelated technically. But I'm a big fan of this channel. Astrum has some really good content.

 

[Dark Corner]

It's moving further away now. December was its closest point to Earth, which even that wasn't particularly close, and it's now continuing on its merry way. Ne'er to return.

Wasn't many photos or footage of it ?

 

[Nuke]

Too far away, I guess. It went closer to Mars than us, and I think the better images of it were captured by the spacecraft orbiting Mars.

 

[Fangs]

I should answer the thread. Where are we headed? Nowhere really.

We are a shitty little extremely lucky planet. A speck of dust caught up in whatever other force is pulling us along. And in around 100 years from now none of us will be here to post about it (I hope this forum lives past 100 years from now to quote myself and others to confirm this truth).

It honestly puts our version of God in perspective. We have a primitive understanding of our own human history here on earth. We will never truly understand what is beyond us. Philosophy and God is our attempt to understand something we will never know. And we all need to get comfortable with it.

 

[BossyC]

I was going to ask @Everlovin' Antichrist or anyone else who is astronomical.

So Hubble said the whole show is expanding and the expansion is speeding up.

I was trying to work out where they said it started relative to our Sun?

Also, is the acceleration a constant or do different chunks of the universe go faster?

Also, If we accept the Big Bang, how could something come from nothing? Surely there was something at the start of the mess?

It just doesn’t make any sense to me that a couple of atoms or whatever just materialises from the void.

I know stranger things have happened like the signing of Packer for $850k, and I’m not putting up anything creationist, but I’m a tad uncomfortable with this explanation.

Any insights appreciated.

Thanks.

As a new member yet to comment on my team the mighty Sydney Roosters, I found this question up my alley, as being a member of a science forum also and an interest in cosmology. Firstly, the evidence that the universe is expanding, was first discovered by Edwin Hubble, with the redshift of distant galaxies. While this is a cosmological redshift, (spacetime expanding rather then galaxies physically moving away) It is also the same reason Doppler redshift works, and is put in practise with Police speed cameras. The opposite of course is blue shift. A car moving towards a speed camera, is doppler blue shifted. we do not see that with cosmology and galaxies moving towards us over large scales. Over smaller scales though, our galaxy, our group of galaxies and even the wall of galaxies to which we belong, then gravity overcomes the spacetime expansion rate.eg: Andromeda, M31, is moving towards our galaxy the Milky Way and will merge with us in around 2 billion years. Other evidence for the expansion of the universe over large scales, is the abundance of lighter elements, like hydrogen and helium, and the CMBR, or Cosmic Microwave Background radiation, or the left over heat of the big bang, which sits at this time at 2.7 Kelvin. The abundance of lighter elements is due to their manufacture just after the big bang itself. All other elements were synthesised when the hydrogen and helium collapses under gravity, ignited at their cores, with the creation of our first stars. When stars go nova, or supernova, they create great pressures and temperatures that go into manufacturing all the other elements. All the elements in your body was manufactured in the belly of stars, that went supernova and spewed their guts into the cosmos. The other query I noticed asked, was where did the big bang come from. To that question, the answer is we don't know. The big bang itself is a scientific theory of the universe/spacetime evolving, (not an explosion as the name may suggest) from a hot dense state, and from 10-45 seconds after the actual event. The third point worth mentioning is a scientific theory. A scientific theory is not an idea or theory you or I may pull out of one's arse. A scientific theory is based on evidence and is our best idea at any specific time. It always remains a scientific theory, so that if further data and evidence, may see that theory re-enforced, added to, modified some, or even scrapped. Scientific theories while many held in high regard, are never set in stone.

 

[BossyC]

And I near forgot, while the universe/spacetime has no boundary that we know of, it does have an observational limit, called our observable universe. This observable universe is around 94 billion Light years in diameter, or 47 billion light years radius. But the big bang happened only 13.83 billion years ago, I hear someone say? yes, but in the meantime, the light from the edge of our observable universe, travelling at light speed, has been travelling through spacetime that is expanding. hence the much larger figure of 94 billion light years.

 

[BossyC]

Cheers.

Is the Milky Way also orbiting around something?

Yep sure does! The Milky way orbits about the center of gravity, or barycenter of our local group of galaxies which include M31 or Andromeda.

 

[BossyC]

. The other query I noticed asked, was where did the big bang come from. To that question, the answer is we don't know. The big bang itself is a scientific theory of the universe/spacetime evolving, (not an explosion as the name may suggest) from a hot dense state, and from 10-45 seconds after the actual event. The third point worth mentioning is a scientific theory. A scientific theory is not an idea or theory you or I may pull out of one's arse. A scientific theory is based on evidence and is our best idea at any specific time. It always remains a scientific theory, so that if further data and evidence, may see that theory re-enforced, added to, modified some, or even scrapped. Scientific theories while many held in high regard, are never set in stone.

While we have no real evidence of anything before 10-45th seconds post big bang, (this is called the quantum/Planck level and is where all our laws of physics and general relativity fail us) we do have some educated speculation. This can be explained by the big bang being the evolution of spacetime, as we know them. Before that was spacetime at the quantum level or as known 'QUANTUM FOAM". This may have been what has always existed (near virtually nothing) and from whence the big bang arose, due to a quantum fluctuation in the quantum foam. But again, essentially speculation rather then a scientific theory.

 

[BossyC]

Yep its orbiting around a huge black hole called Sagittarius A. There is documentary about on Netflix Black Holes The Edge of what we know.

​

And our galaxy including Sag: A of course, is orbiting about a barycenter of our local group of galaxies, including M31 or Andromeda.

 

[Mojo]

To quote The HebeeJebees:

The world is very very large
And butter is better than marge
And love is better than hate
The world is very very big
And bacon comes from a pig
But it's you I really want on my plate
So I'll sing you

 

[Mojo]

 

[The Silverdale Phantom]

@Generalzod any Jupiter for my iPhone?

 

[BossyC]

Carl Sagan, in my opinion, the greatest educator of our time. The pale blue dot narrative should be compulsory learning in school, everywhere.

 

[Mojo]

Carl Sagan, in my opinion, the greatest educator of our time. The pale blue dot narrative should be compulsory learning in school, everywhere.

The numinous - sense of wonder - where science and poetic prose combine …. I love it …. In small doses.

Just in case the video link doesn’t work:

Pale Blue Dot

Carl Sagan

Look again at that dot. That's here. That's home. That's us. On it everyone you love,

everyone you know, everyone you ever heard of, every human being who ever was, lived

out their lives. The aggregate of our joy and suffering, thousands of confident religions,

ideologies, and economic doctrines, every hunter and forager, every hero and coward,

every creator and destroyer of civilization, every king and peasant, every young couple in

love, every mother and father, hopeful child,

inventor and explorer, every teacher of

morals, every corrupt politician, every

"superstar," every "supreme leader," every

saint and sinner in the history of our species

lived there--on a mote of dust suspended in a

sunbeam.

The Earth is a very small stage in a vast

cosmic arena. Think of the rivers of blood

spilled by all those generals and emperors so

that, in glory and triumph, they could become

the momentary masters of a fraction of a dot.

Think of the endless cruelties visited by the

inhabitants of one corner of this pixel on the

scarcely distinguishable inhabitants of some

other corner, how frequent their

misunderstandings, how eager they are to kill

one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged

position in the Universe, are challenged by this point of pale light. Our planet is a lonely

speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no

hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in

the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not,

for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is

perhaps no better demonstration of the folly of human conceits than this distant image of

our tiny world. To me, it underscores our responsibility to deal more kindly with one

another, and to preserve and cherish the pale blue dot, the only home we've ever known.

— Carl Sagan

 

[Generalzod]

@Generalzod any Jupiter for my iPhone?

My telescope isn't for planetry photos you can see it but it way to small.

 

[Generalzod]

Carl Sagan, in my opinion, the greatest educator of our time. The pale blue dot narrative should be compulsory learning in school, everywhere.

The movie Contact is awesome.

 

[BossyC]

The movie Contact is awesome.

I'll tell you one thing about the universe, though. The universe is a pretty big place. It's bigger than anything anyone has ever dreamed of before. So if it's just us... seems like an awful waste of space. Right? Ellie Arroway: