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Smaller Than Earth-Sized Exomoon Discovered?
astroengine writes "Through the technique of microlensing, a candidate exomoon has been discovered in orbit around a free-floating planet about 1,600 light-years away toward the galactic bulge. The microlensing event, MOA-2011-BLG-262, was detected by the MOA-II telescope at Mt. John University Observatory (MJUO) in New Zealand and it appears to have a mass of approximately half that of Earth. The host planet is around 4 times the mass of Jupiter. Unfortunately there cannot be further studies of his particular exoplanet-exomoon pair (as microlensing events are transient and random), so the astronomers who made the discovery are remaining cautious and point out that although the exoplanet-exomoon model fits the data the best, there's a possibility that the lensing object may have been a more distant star with a massive exoplanet in tow. Microlensing surveys are, however, sensitive to low mass exoplanets orbiting massive free-floating planets, so this is a tantalizing first-detection. The study's pre-print publication has been uploaded to the arXiv."
OK, proceed to normal discussions.
How do we know it's there? Sure they told us, but it's not like we can check it ourselves. It's not like we have a spaceship, which can take us there and see for ourselves. With all the NSA talk it could actually be healthy to think wider and more generally who can be trusted? This is specially interesting with claims nobody else can test for themselves.
Having said that I have to say that it is entirely possible that this is the truth and I have no reason not to believe their reported find. I think it is interesting, but to be honest it is of little use. We kind of knew other planets could have moons and it isn't like we will start to mine this one or anything,
offended Some
...except Europa. Attempt no landing there. Use them together in peace.
Free floating planets give me hope. There are use cases for free floating planets. Stars explode. It's nice to know there are some places out there we can have low-maintenance long-term storage options deep inside, safe from cosmic rays or exploding stars -- We might not have to build them from scratch, or worry about how to power EM shields indefinitely. We ever make it off this wet rock before the sun explodes the Andromeda Galaxy will be merging with ours. That's a whole new galaxy full of resources, and it's heading our way. We'll probably need new stars and planets to harvest eventually, so that's a good thing.
Unfortunately it doesn't look like life on Earth will be able to survive the sun's explosion, and we can't tow the planet in enough time to sling it away for posterity's sake -- Sure would be nice if we could though, maybe it's not impossible, but who can say what a few billion years of new technology will bring. It would be cool to visit the free floating frozen origin of our species rather than let it be fried to a crisp, and/or re-liquefied. The crust just isn't thick enough to burrow down in thanks to our large moon-making collision. C'est la vie.
"... mass of approximately half that of Earth"
How many moon units would that be?
how truly pointless this stuff is? Sure, there are a few astronomy geeks who are able to make a living (from grants, rather than productive economic activity) studying this stuff, but it has ZERO potential to actually produce any benefit and therefore generate value in the economy - it will always be a charity or a hobby.
Only one nation has even managed to put a man on the MOON (orbiting THIS planet) and that nation is not now even capable of putting a CHIMP into orbit (something it COULD do 50 years ago). It's unlikely that we will put a man on even the NEAREST planet orbiting THIS star in the next 20 years. At the current rate of progress, it may be CENTURIES before we put a man on any of the interesting moons of even the big planets orbiting THIS star.
Even if we were ready to go now, it would take a spaceship thousands of years to get from here to ANY of the "promising" exoplanets - so the people who pay for the trip would never get any return on their investment, the people who embarked would die of old age having never gotten out of our solar system (the voyagers have taken 40+ years to just reach the edge). By the time any human got to any exoplanet and sent word back to Earth, it's possible life here could be extinct or the people here could be so introverted they do not care and are not even listening. Anybody from the exoplanet making a return to earth would die en-route and his descendents (generations later and arriving thousands of years later) might well be considered "aliens" rather than triumphant returning explorers. The distances mean that there is no possibility for commerce or other interactions between humans here and humans there.
It's fascinating to contemplate distant worlds, but it's simply not a productive activity and will not be until we first find a way to travel faster than light. Every dollar spent looking for other worlds orbiting other stars is a dollar wasted that COULD have been spent getting man back to the moon, getting man to Mars, or doing basic research on faster spacecraft propulsion.
They gonna call it "Endor"?
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Or
"That's no moon"
Silence is a state of mime.
There was this one time, when like, I thought this one thing was a bug, but when I got closer it was a pebble.
Did I ever tell you about this one time when I thought I seriously fucked my toe up, but I only stubbed it?
I remember once when I walked a long time, like it felt like tons of hours and miles, but it was only an hour and it was only like three miles. I dunno I guess I was tired.
"Stratigraphically the origin of agriculture and thermonuclear destruction will appear essentially simultaneous" -- Lee