Interesting Space Facts.
Discussion
227bhp said:
annodomini2 said:
227bhp said:
The Moon gets 38mm further away from The Earth every year, one day it will just be a speck in the sky like a star.
It will only move out another ~2900 km before the Earth is swallowed by the Sun, so it will never be a speck in the sky.
There're as many cells in a human* as stars in a galaxy, yet take the entire human race and compress it to neutrino density you'd fit everything into a sugar lump.
At black hole density the human race would fit into a proton sized event horizon.
(*Double the number of cells if you count the microbiota... :shudder: )
[/roughly]
At black hole density the human race would fit into a proton sized event horizon.
(*Double the number of cells if you count the microbiota... :shudder: )
[/roughly]
Voyager 1 spacecraft, launched by NASA from Florida in 1977, is the furthest manmade object from Earth.
It is currently in interstellar space, roughly the middle of our Milky Way Galaxy, traveling at 38k mph, some 21 billion km from its launchpad.
You can monitor Voyager 1 in real-time here:
http://voyager.jpl.nasa.gov
It is currently in interstellar space, roughly the middle of our Milky Way Galaxy, traveling at 38k mph, some 21 billion km from its launchpad.
You can monitor Voyager 1 in real-time here:
http://voyager.jpl.nasa.gov
annodomini2 said:
227bhp said:
The Moon gets 38mm further away from The Earth every year, one day it will just be a speck in the sky like a star.
It will only move out another ~2900 km before the Earth is swallowed by the Sun, so it will never be a speck in the sky.jmorgan said:
annodomini2 said:
227bhp said:
The Moon gets 38mm further away from The Earth every year, one day it will just be a speck in the sky like a star.
It will only move out another ~2900 km before the Earth is swallowed by the Sun, so it will never be a speck in the sky.Waaaaay back in Oct 2012
Nom de ploom said:
next summer - all being well my honeymoon will be an arctic cruise.
I cannot wait for perfectly clear skies just o be able to sit there and well... look up basically.
I've got a Nikon D40 so I hope (with a bit of learning beforehand) to be able to use it to capture some nice images.
So when are we going to see them?I cannot wait for perfectly clear skies just o be able to sit there and well... look up basically.
I've got a Nikon D40 so I hope (with a bit of learning beforehand) to be able to use it to capture some nice images.
Yipper said:
It is currently in interstellar space, roughly the middle of our Milky Way Galaxy, traveling at 38k mph, some 21 billion km from its launchpad.
It is only just into interstellar space, and nowhere near the middle of the MW (25000+ light years away) unless it just popped through a wormhole.Yipper said:
Voyager 1 spacecraft, launched by NASA from Florida in 1977, is the furthest manmade object from Earth.
It is currently in interstellar space, roughly the middle of our Milky Way Galaxy, traveling at 38k mph, some 21 billion km from its launchpad.
You can monitor Voyager 1 in real-time here:
http://voyager.jpl.nasa.gov
Quite scary really to think that on the scale of things that the spacecraft has not even got off the backdoor step into the garden yet.It is currently in interstellar space, roughly the middle of our Milky Way Galaxy, traveling at 38k mph, some 21 billion km from its launchpad.
You can monitor Voyager 1 in real-time here:
http://voyager.jpl.nasa.gov
These numbers are approximate and I got them from Googling while reading about the Fermi Paradox, but I find them interesting anyway...
There are approximately the same number of galaxies in the observable universe as there are stars in the Milky Way (300 billion / 300,000,000,000). Assuming the Milky Way is average, that makes about 90,000,000,000,000,000,000,000 stars in total. Around 12,000 stars for every grain of sand on Earth.
On the clearest nights, you can see approximately 2,500 stars in the sky - that is 0.000000008% of the stars in the Milky Way or 0.00000000000000000003% of all the stars in the observable universe.
Approximately 10% of stars observed so far have properties similar to our Sun. This means the number of stars in the observable universe similar to our Sun is 9,000,000,000,000,000,000,000.
It is thought that approximately 25% of these stars have rocky planets orbiting at a similar distance to Earth, (which could potentially support water/life). If this is true, then there are approximately 2,250,000,000,000,000,000,000 planets similar to Earth.
Now we're just guessing... But let's be conservative and say that only 1% of those planets have developed any kind of life, and only 0.1% of planets with life eventually evolve into intelligent life.
That gives us 22,500,000,000,000,000 planets with intelligent life in the observable universe. Or 75,000 in the Milky Way alone.
Some of those planets are billions of years older than Earth. Think of the scientific advances that humans have made in the last 1,000 years... Now imagine what would be possible in billions! They should have been able to colonise every part of the galaxy by now, if not the universe.
So where are they?
There are approximately the same number of galaxies in the observable universe as there are stars in the Milky Way (300 billion / 300,000,000,000). Assuming the Milky Way is average, that makes about 90,000,000,000,000,000,000,000 stars in total. Around 12,000 stars for every grain of sand on Earth.
On the clearest nights, you can see approximately 2,500 stars in the sky - that is 0.000000008% of the stars in the Milky Way or 0.00000000000000000003% of all the stars in the observable universe.
Approximately 10% of stars observed so far have properties similar to our Sun. This means the number of stars in the observable universe similar to our Sun is 9,000,000,000,000,000,000,000.
It is thought that approximately 25% of these stars have rocky planets orbiting at a similar distance to Earth, (which could potentially support water/life). If this is true, then there are approximately 2,250,000,000,000,000,000,000 planets similar to Earth.
Now we're just guessing... But let's be conservative and say that only 1% of those planets have developed any kind of life, and only 0.1% of planets with life eventually evolve into intelligent life.
That gives us 22,500,000,000,000,000 planets with intelligent life in the observable universe. Or 75,000 in the Milky Way alone.
Some of those planets are billions of years older than Earth. Think of the scientific advances that humans have made in the last 1,000 years... Now imagine what would be possible in billions! They should have been able to colonise every part of the galaxy by now, if not the universe.
So where are they?
Eric Mc said:
Distance.
I'm not sure that answer actually solves the conundrum although (on the face of it) it appears to.Using the stepping-stone analogy if there are hundreds of thousands of races more advanced than our own then one race ought to have colonised the galaxy by now (albeit slowly) but hasn't.
http://www.sentientdevelopments.com/2012/01/new-ma...
Not even Von Neumann probes.
Now I'm only quoting this for giggles but "So, the next time somebody smugly shrugs off the Fermi Pardox by suggesting that "it takes too long to colonize the Galaxy" or that "there hasn't been enough time," or that "the Galaxy is too big," tell them to shut-up and read this paper."
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