With all the exoplanet hunting going these days, astronomers have now logged more than 500 planets orbiting other stars in the Milky Way. Detecting planets in other galaxies, however, is still beyond the reach of scientific technology. But researchers have now discovered the next best thing – a planet of extragalactic origins orbiting a star within our galaxy that was deposited there billions of years ago when the Milky Way swallowed up a smaller dwarf galaxy.
The star, known as HIP 13044, resides some 2,000 light years from Earth in a part of the galaxy known as the Helmi stream – a group of stars that belonged to a smaller galaxy that was absorbed by the Milky Way six to nine billion years ago. And the planet – HIP 13044 b, is interesting for a variety of reasons beyond the fact that it's the first extragalactic planet ever detected.
HIP 13044 b has a minimum mass of 1.25 times that of Jupiter, so it's a relatively large planet. And it is orbiting really close to its host star, making a full orbit in just 16.2 Earth days. At its closest point during its elliptical orbit, the planet comes within one solar diameter from its star.
It's hypothesized that HIP 13044 b didn't always orbit so closely. The planet is unique for study because it apparently has survived its star's red giant phase, when the star expands to massive size after using up the hydrogen supply at its core. It's one of only a few exoplanets to have survived this event, and could lend some interesting insights into the fate of our own solar system as our own sun is on pace to undergo its own red giant phase at some point in the future, likely around 5 billion years from now.
HIP 13044 b was likely pulled in closer to its host during this period, when any planets that were inside its orbit were swallowed up by the star. HIP 13044 b might not be long for this galaxy either; the star has collapsed back down as part of its evolutionary cycle, but as it nears the end of its life it will expand again, likely engulfing the planet. It's a fate our own solar system, and our own planet, likely shares.
apparently nobody proof-reads anything these days
"are from a smaller dwarf gallery that was absorbed by the Milky Way billions of years ago."
a dwarf gallery:D
yeah...planets and stars and galaxies are cool and all, but why waste our time studying anything but planets with potential life or that can be inhabititable by humans. the rest are all rocks or rocks on fire that are trillions of miles away and will never be useful for anything other than pretty pictures for computer wallpapers
A lot of the applied science we have today started as pure science at a previous stage of history. Also, it's hard not to think of knowledge as an end in itself.
I disagree with e-rock.. I think it is important to study planets that do not have life on them because they may have valuable minerals for us to use. Also, many of the greatest are made by accident, so by learning about seemingly useless things, we may find great information.
"I disagree with e-rock.. I think it is important to study planets that do not have life on them because they may have valuable minerals for us to use."
Mk, so if the planets do have valuable minerals for us to use, like the one stated in the article, we only have to travel 2000 light years to get there, then travel 2000 light years back. We probably won't posses that kind of space-traveling technology for another 100-1000 years. So, those "valuable" minerals, are kinda useless as e-rock stated.
Well, simply put, looking at this planet is a learning tool for cosmological history. It was engulfed by our galaxy FROM another galaxy, that's pretty cool. And most of this stuff can be found by using simple physical principles. So it probably didn't take many resources to figure out it's orbital path and period.
How will we ever find out about other , possibly inhabitable, planets if we never look? It can't host life, so what? Tons of other planets can't. You can't just expect astrologists to look into their telescope and bang, find inhabitable planets. If that was the case, we'd have a HUGE space program, and astrologers would be rockstars. Basically, name one other planet we've found that is inhabitable - I'm only coming up with that one they found around Gliese 581 (maybe). Even more importantly, they've only mapped out 500 planets... 500 in just our galaxy, that's basically nothing. We are merely in a discovery phase of comsological exploration - once we understand what's out there and where its at, we can start worrying about inhabitable planets. So it's pretty unfair to say that this discovery is unimportant, what have you discovered? If you want inhabitable planets, train YOUR sights on the stars and see what you come up with.
@ Haze and E-rock. yeah... and learning is dumb! why would anyone want to figure out anything new about life. its mans nature to understand everything.