Which planet in our galaxy is the oldest?
454222
Check this out:\n\n"NASA's Hubble Space Telescope precisely measured the mass of the oldest known planet in our Milky Way galaxy. At an estimated age of 13 billion years, the planet is more than twice as old as Earth’s 4.5 billion years. It’s about as old as a planet can be. It formed around a young, sun-like star barely 1 billion years after our universe’s birth in the Big Bang. The ancient planet has had a remarkable history because it resides in an unlikely, rough neighborhood. It orbits a peculiar pair of burned-out stars in the crowded core of a cluster of more than 100,000 stars. The new Hubble findings close a decade of speculation and debate about the identity of this ancient world. Until Hubble’s measurement, astronomers had debated the identity of this object. Was it a planet or a brown dwarf? Hubble’s analysis shows that the object is 2.5 times the mass of Jupiter, confirming that it is a planet. Its very existence provides tantalizing evidence that the first planets formed rapidly, within a billion years of the Big Bang, leading astronomers to conclude that planets may be very abundant in our galaxy."
485969
There are lots of different types of stars, all with different 'lifespans'. Ours is about 4.5 Billion years old and should 'live' to the ripe old age of about 10 Billion years old.
1176345
the earth is about 4.5 billion years old
686354
oldest human races are farthest away from cradle land
154496
Earth is the third planet from the Sun. It is the largest of the solar system's terrestrial planets, and the only planetary body that modern science confirms as harboring life. Scientific evidence indicates that the planet formed around 4.57 billion (4.57×109) years ago, and shortly thereafter (4.533 billion years ago) acquired its single natural satellite, the Moon.
526016
Humans found out that they live in a small living planet in the middle of a very-small galaxy. our galaxy is in the middle of a small super-cluster too. And they dont know more about this.
1073938
Well dear....we aren't centrally placed in our milky way galaxy.....our solar system lies at a distance of about 30,000 light years from its centre....and we don't know the extremities of our universe yet hence our position with respect to the universe can't be measured..
237723
Andromeda is just 2.5 million light years away.\nOur sun is only halfway through it's 4.6 BILLION year life.\nSolar systems closer to the Shapley Center of our Milky Way galaxy are younger.
40765
Jupiter is the largest planet in this solar system overall, but Earth is the biggest non-gas planet.
247943
A planet is classified by its size/mass.  They are currently reveiwing the catagory, which may end up in pluto being excluded from the solar system.  \nAs far as getting to another galaxy, there is a way, we just haven't figured it out yet.  The closest galaxy is andromeda (sp), which is billions of lightyears away.  And since we can't even reach the speed of light, well, intergalactic travel isn't very likely in the near future.
412196
Not in our lifetime.  It takes 1,500 years for it to complete its eliptical orbit between our Sun and a dead sun outside our galaxy.  We have a better chance meeting helpful space visitors before planet X will return.
730967
The earth is BILLIONS of years old. That's 4500 Million years old , (about).\n\nPeople think know this because of four ways of thinking about it.\n\n1. We know about how old the sun is. \n\nThink of a soda with ice. when we start drinking theres plenty of soda and a the ice is frozen and the soda is cold, when the soda gets "older" it is more watery because the ice has all melted, when the soda gets really "old" the soda becomes flat and doesn't taste good. \n\nIt's kinda like that with the sun, we can see other stars, some that are young and some that are old and when we look at them all we can know the sun is about 4.5 billion years old based on how it behaves. \n\nStars are also a little bit like people in how they behave. Very young sun-like stars are bright and white or yellow and very active. Adolesent stars are not as active but are still bright and usually yellow or light orange in color. Middle age stars are orange and not quite as active. Old stars are darker colors of orange and even less active,and may start to get fatter and very old stars will grow bloated , turn redish and then become more dim and evenually end up becoming nurserys for other stars or planets after they die.\n\nWe think the earth formed at the same time as the sun, so that is about 4.5 billion years ago. \n\n2. Some elements on earth "decay" at a certain rate, think of it like a rusting tool in a shed or work area. One of the metals, Uranium decays over billions of years , almost all of the Uranium on the earth is of the same "decaying" age. That age is about 4.5 billion years ago. Oxygen and other elements have other "decay" rates and these also tend to support the fact that the earth has had oxygen in the atmosphere for about 3 billion years.\n\n3. We know the earth is old because of fossils , some fossils are of shells of sea animals that are very simple. Some of these shells are found on the highest mountains in the world. So if we say these shells were once deep in an ocean "how often do earthquakes move this mountains" and "how much does the mountain move up or down up each time", if we then say ok "we've been here watching this mountain for 200 years and there were two earthquakes and each earthquake  moved the mountain 1 inch. How long would it take to move 100 miles and 3 miles up. \n\nBy answering questions like that we can figure out how old certain mountains are, by doing this all over the earth the oldest mountains/rocks are in Australia and Canada and they are were formed a little less than 4 billion years ago.\n\n4. We think the moon formed from the earth being hit by another planet about the size of the planet mars, and we think that this happened about 4 to 3.5 billion years ago based on how far the moon is moving away from the earth and the incline of the earth and the moon.\n\nSome religions, notably the evangelical movement in the US, believe the earth was formed by God in 6 days. They figure based on the Bible backwards from when someone dies or was born backwards from Jesus , to King David, to Noah, to Adam and Eve and based on that math the Earth is only 6000 years old.  \n\nThis is not supported by any scientists as a good, reasonable date as the planet's surface is too large and would still be mostly molten rock if it was only 6000 years old and there would be no oceans or life just a big molten radioactive lava ball in space like a red hot bigger version of the moon...\n\nOther religions say that the earth was the result of a giant fight amongst the Gods and almost every society of man has what is called a "creation myth" which is how primitive people explain good questions when they don't _know_ or can't figure out the answers.
604824
The astrobiology folks at NASA have calculated that there are between one and thirty billion habitable planets in our Milky Way Galaxy.  If our solar system is typical,  you can multiply that by about 10 to get total planets: between 10 and 300 billion.  \n\nSo where is everybody?
5355
No one knows.\n\nThere are about 10 planets in our solar system, depending on whom you ask.\n\nAround 100 planets have been detected in other solar systems.\n\nThere are at least 200 billion stars in the Milky Way Galaxy (ours).\n\nIf the average number of planets per star is 10, then there are 2000 billion or 2 trillion planets in our galaxy.\n\nNo one knows how many billion galaxies are in the Universe.
1123060
Maybe somewhere, we will probably never know! There is a high chance that in another galaxy though that there is another inhabitable planet similar to earth with life living on it, i cant believe that it has only happened to one planet in one galaxy in all of space! That would just be madness!
826729
its been millions of years
705988
My gut agrees with you, but I wouldn't jump to any conclusions. A sobering (and excellent) read is Rare Earth by Ward and Brownlee. One is an astronomer, the other a geologist. They make a convincing case that sentient life elsewhere in the universe is probably quite rare. At a minimum, they make minced meat out of the Drake Equation. Still, with so many possibilities ...\n\nThe other thing to remember is that first and possibly second generation of post-Big Bang stars could never have supported planets with life of any kind. It took billions of years before stars produced sufficient quantities of heavy elements that are essential for life.\n\nand, all those stars and all those galaxies don't exist simultaneously. As we look farther out into space, we are more and more likely looking at objects that no longer exist.\n\nso, having said all that, we must consider this. a) sentient beings are probably quite rare - whether you accept Ward and Brownlee's extreme argument or not. b) that life could only have existed for, say, the last 8 or 9 billion years of the universe's existence. c) the distances to other stars in our galaxy are vast, but the distances *between* the galaxies are mind boggling vast (there's a reason that even in Star Trek, with it's fantasy warp drive, the story lines are all confined to our own galaxy).\n\nJust food for thought.