Appreciation of Cosmic Distances

[Maddad]

I thought that I'd posted this earlier, but can't find any trace of it when I search *Shrugs* The project of describing to a non-scientist how incredibly far away the stars are started when I wanted to show the difference between the distance to the space station and the distance to the Moon. It snowballed from there, adding a step at a time until the numbers got beyone anyone's ability to comprehend. Many of us can provide a number, but none of us understand what those numbers mean in concrete, every-day references.<hr width="80%" noshade="" /><br /><br />It is so difficult to launch men into orbit that so far only the United States, Russia, and very recently China have done so. All of us have seen the breathtaking videos of astronauts floating 400 kilometers up near the space station as the blue marble of Earth turned below. However, many of us had not yet been born when we sent men a thousand times further to the Moon. The fact that nobody has ever duplicated that feat, even 35 years later, underscores the difficulty of that achievement.<br /><br />Some people feel that going just a little bit further from the Moon bring us to Mars. The Red Planet at its closest though is well more than a hundred times further away from us than the Moon is. Comparing the distance to the Space Station and to Mars is similar to comparing the distance across your fingernail to a kilometer.<br /><br />In class, we mentioned the definition of a lightyear, but we really did not appreciate its meaning. Light moves so fast it would zip around the world seven times in a second, and yet it must travel an entire year at that pace to cover that lightyear. Stellar distances are so vast that light would travel for four years to reach our nearest neighbor Proxima Centauri. This is 750,000 times as far away as Mars, and yet many people think of Mars as the next stepping-stone to the stars.<br /><br />Proxima Centauri is just the nearest star, so other stars in our galaxy are vastly further yet. The

 

[Maddad]

And yet Andromeda is the closest galaxy to us, like the next grain of sand on the beach.

 

[pizzaguy]

So where are all the UFO's coming from? ROFL LH!<br /><br />Gotta get that wormhole thing in the garage working... <div class="Discussion_UserSignature"> <font size="1"><em>Note to Dr. Henry:  The testosterone shots are working!</em></font> </div>

 

[Maddad]

You get a stargate operational and I'll buy the pizzas for the trip.

 

[glutomoto]

Thanks for reminding me about: Molecular expressions where, <i>"You can View the Milky Way at 10 million light years from the Earth. Then move through space towards the Earth in successive orders of magnitude until you reach a tall oak tree just outside the buildings of the National High Magnetic Field Laboratory in Tallahassee, Florida. After that, begin to move from the actual size of a leaf into a microscopic world that reveals leaf cell walls, the cell nucleus, chromatin, DNA and finally, into the subatomic universe of electrons and protons."</i><br /><br />And of course everyone knows the universe is big, really big, large, emense, enormous, and <div class="Discussion_UserSignature"> </div>

 

[Maddad]

One of my very largest images is Hubble's Deep Space view. It's something like 5,000 pixels wide. The individual points of light are galaxies, not individual stars. It's enough to make you stop dead in your tracks thinking.

 

[kmarinas86]

<font color="yellow">One of my very largest images is Hubble's Deep Space view. It's something like 5,000 pixels wide. The individual points of light are galaxies, not individual stars. It's enough to make you stop dead in your tracks thinking.</font><br /><br />I think the deeper we look into space the more we will realize that there yet billions of lightyears more gold and mature galaxies behind the blue and wild galaxies we see in Hubble Deep Field. I "screened" the exposure so that I could see the faint details more easily. It seems like that there are still more galaxies behind. Some of it "could" be noise, but I think Hubble is more optically precise than that and that they are really focused areas of light.

 

[Maddad]

Those you mentioned are dwarf satellite galaxies of our own. If you want to split hairs, then Andromeda is the closest independent galaxy to ours. Interestingly, Andromeda has a couple of satellite galaxies of its own. This is a half-sized picture because the original is just too honking huge: http://www.maddad.org/astronomy/images/andromeda01a.jpg

 

[qzzq]

Cosmic distances?<br /><br />Our entire solar system orbits around the center of the Milky Way Galaxy. It does so travelling at a speed of 220 km/s, or 792,000 km/h, or 6,937,920,000,000 meters every year. Still it takes 220 million Earth years to orbit our galaxy once, to make one cosmic year. <div class="Discussion_UserSignature"> <p> </p><p>***</p> </div>

 

[averygoodspirit]

Andromeda is not the closest galaxy to us. There are the large and small Magellanic Clouds in our local group that are closer. (Steve beat me to it)<br /><br />Andromeda is not all that independent. It’s headed right for us and will hit us eventually. <br /><br />Einstein was wrong. The universe is not infinite; it’s finite. Eventually, the universe will cease to exist. Human stupidity is also finite. One can only be ignorant to a certain level before they cease to exist. <br /><br /> Molecular expressions is really cool. It’s true too, but you can go much further than that. <br /><br />It took a million seconds of exposure or 11.57 days of exposure to make the deep field photograph. How we could keep it perfectly still and locked on for that long is a great accomplishment in itself.<br /><br />I’m all for saving the Hubble. We have better in development, but Hubble is too valuable to let it die now. We might be able to give it a twin, then separate and synchronize them. That would give us a pair of huge binoculars wouldn’t it?<br /><br />Congress appropriated some extra funds to save it, I think about 300 million dollars if I’m not mistaken. <br /><br /> <div class="Discussion_UserSignature"> </div>