Up There

[terryc]

Hi all

A little Saturday morning question:

Can you ever comprehend what's ''out there''. You know the planets, the Stars, the distances!!

I am only just getting back to learning and I think I have scrambled my brain (what I have) already.

[Stu]

12 minutes ago, terryc said:

Hi all

A little Saturday morning question:

Can you ever comprehend what's ''out there''. You know the planets, the Stars, the distances!!

I am only just getting back to learning and I think I have scrambled my brain (what I have) already.

The answer to that for me is 'NO'!! I can't even begin to comprehend the distances and extent of what is out there, but that's the fascinating thing about observing the stars. Knowing that photons that have travelled for millions of years are hitting the back of your eye is pretty mind blowing!!

[Scott]

I was talking to my wife about this a couple of nights ago. when we travel to Australia, after 24 hrs of listening to the drone of the engine we're ready to get off... and we've covered 12000 miles if I wanted to do that 20 times I'd just about make the moon.

No,I  don't think anyone can really comprehend distances away from our little rock.

[terryc]

Hi scott.

Just been looking at your pics on flickr. Fantastic pics!! What part of the solar system did you find that Yamaha, lovely old bike!!

[ronin]

Lots of hydrogen, some helium, assorted buts of nuclear waste from old stars - carbon, oxygen and things.

Quite a few stars, some a bit odd but still stars, remains of stars that have gone bang and died leaving assorted nuclear waste, white dwarfs, neutron stars, and the occasional black hole.

Some of the stars have collected together into galaxies, would appear "normal" for them to collect into a galaxies, hopefully makes them feel happy. These galaxies can be of assorted sizes and shapes, and some of the galaxies collect together into clusters, occasionally one "bumps" into another. We are it would seem in an "average" galaxy of about 100,000,000,000 stars.

Between them all is varying amounts of "space". And it would appear that the space is increasing.

Apparently some "matter" we cannot (yet) see, measure or detect directly, although I have noticed that more references are asking "Is there really dark matter?" At one talk the term used was "The observation showed there was less gravity then expected." Not less "matter". Sheffield Uni is having a series of talks on DM in July for anyone in the area.

We don't know what is causing the "space" to increase and in keeping with convention we have said it is getting bigger owing to "dark energy" causing the increase in what is in effect nothing. "Dark" apparently being the prefix for "we haven't a clue."

Seems pretty simple.

 

[Gina]

Oh no it isn't

[bejay1957]

Space is big. Really big..

[terryc]

Aaaahhhh That makes it seem much better. Ronin, I understand everything now!! Whats next!!

 

[astro mick]

I cant get my around the Universe is expanding."The old proverbial,What is it expanding into".

Does it create Space and Time as it does this.

Outside my box I,m afraid.

Mick.

[terryc]

I only asked after reading last week about sending a ''chip'' with lasers being fired at it, into outer space, some 25 trillion miles away. I am no good at maths but that is a long long way!!

[ajk]

25 trillion miles on a scale of the Universe is nothing, it's just a wee tiny hop.

[LukeSkywatcher]

The scale of the universe is way too much for us mere humans to comprehend. Even those of us that can do maths and work out distances,size etc, i dont think even fully comprehend it as we are talking about sizes and distances that we simply do not,have not,can not experience here on Earth. Probably the furthest distance i have walked here on Earth is about 3 miles......so i understand exactly how long a 3 mile distance is. Ive flown thousands of miles on a flight and know how long it takes, so i understand that distance.

To understand sizes and distances in astro terms is something i never will comprehend.

I once heard that if the Orion Nebula was as close to Earth as the Moon is, that it would fill the whole of the sky in all directions when viewed from any position on the planet. It would be all we ever saw when we look upwards be it during the day or the night. The Orion nebula isnt even big in the grand scheme of things. Its probably microscopic in relation to most of the rest of the objects in the universe.

[johnfosteruk]

 it's funny how everyone's brain works isn't it. I kind of comprehend the scale and mechanics of the universe but its the small stuff I can't even begin to make sense of. No matter how much I read I can't Understand particles, forces at that scale, how it all behaves etc. It seems like a load of paradoxes to me. 

[John]

This version of the Hubble Ultra Deep Field imaging beings home the scale of the Universe to me. It's quite a big image (4.3mb) so you can zoom into it and find all sorts of different shaped galaxies, each with billions of stars in of course. If you zoom out, down at the lower left there is a superimposed image of the moon with the total size of the Hubble Ultra Deep Field next to it for scale - all that and it's just a tiny patch of what is out there

 

[Joe12345]

Perhaps if our retinas were 3d it would be easier.....but until some university manages to build one, no, I doubt anyone could imagine such large distances. Our problem is that we only see angles, so we can only guess sizes, and no one would naturally guess anywhere near the reality.

[LukeSkywatcher]

6 hours ago, John said:

This version of the Hubble Ultra Deep Field imaging beings home the scale of the Universe to me. It's quite a big image (4.3mb) so you can zoom into it and find all sorts of different shaped galaxies, each with billions of stars in of course. If you zoom out, down at the lower left there is a superimposed image of the moon with the total size of the Hubble Ultra Deep Field next to it for scale - all that and it's just a tiny patch of what is out there

 

John, the Hubble deep field image is without doubt the greatest image mankind has EVER taken of the universe. I watched the show on tv about the history of the telescope and it said that in that single image of a blank area of the night sky that there are only 3 single stars in the image. Every other point of light in that image is a GALAXY.

Mind blowing.

[symesie04]

On 16/04/2016 at 00:37, LukeSkywatcher said:

John, the Hubble deep field image is without doubt the greatest image mankind has EVER taken of the universe. I watched the show on tv about the history of the telescope and it said that in that single image of a blank area of the night sky that there are only 3 single stars in the image. Every other point of light in that image is a GALAXY.

Mind blowing.

Sure ive spotted at least 4

 

Of course we cant grasp the scale of whats out there, even astrophysicists that spend their life on it cant. Thats why they have to convert the scales into more manageable quoto (lightyears and parsecs) but even then they can only apply it to "local" studies. But the question is is the universe immense or are we just really tiny?

[Gina]

"It's all relative"

[LukeSkywatcher]

On 17/04/2016 at 10:16, symesie04 said:

Sure ive spotted at least 4

 

Of course we cant grasp the scale of whats out there, even astrophysicists that spend their life on it cant. Thats why they have to convert the scales into more manageable quoto (lightyears and parsecs) but even then they can only apply it to "local" studies. But the question is is the universe immense or are we just really tiny?

I agree. Stars show diffraction spikes. I spot 5 in the image.

[KenG]

Okay, just to put everything in scale - this by the way is from Burnhams Celestial Handbook.

If the radius of the Solar System was 7' 0'', then on this scale the distance from the Sun to the Earth would be one inch and one mile would equal one light year, therefore the distance to the Pleiades which are 410 light years distant, would be 410 miles.

Earth would be smaller than a full stop on this post and the Moon would be microscopic. The nearest star would be about five miles away.

[majer]

Some time ago I've seen a short movie, where there was a Solar System scale described, using a jet, flying with 1000 km/h speed. And with this jet one can fly around the Earth within 40 hours, but to fly around the Sun, one will need over half a year, and a journey from the Earth to the Sun would last over 17 years. My calculator says, that  a journey to the nearest star with such a speed will last over 4.6 million years.

The fastest manmade thing so far is the Voyager 1 spacecraft, which is moving with a speed of 17 km/s. And its hypothetic journey to the nearest star would take almost 76000 years.