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Astrophysicists Find "Impossible" Planet
SpuriousLogic writes "Scientists have discovered a planet that shouldn't exist. The finding, they say, could alter our understanding of orbital dynamics, a field considered pretty well settled since the time of astronomer Johannes Kepler 400 years ago.
The planet is known as a 'hot Jupiter,' a gas giant orbiting the star Wasp-18, about 330 light years from Earth. The planet, Wasp-18b, is so close to the star that it completes a full orbit (its "year") in less than an Earth day, according to the research, which was published in the journal Nature.
Of the more than 370 exoplanets — planets orbiting stars other than our sun — discovered so far, this is just the second with such a close orbit.
The problem is that a planet that close should be consumed by its parent star in less than a million years, say the authors at Keele University in England. The star Wasp-18 is believed to be about a billion years old, and since stars and the planets around them are thought to form at the same time, Wasp-18b should have been reduced to cinders ages ago."
This study does demonstrate that either the measurements are wrong or our understanding of orbital dynamics is wrong. Knowing the former is important because it tells us we have to alter how we make the measurements and knowing the latter is important because it tells us we have to alter our understanding of physics. So it's the very antithesis of hubris.
No kidding!!! What do you say at this point?
Perhaps it was thrown from a different solar system and captured by its star.
Free Martian Whores!
Not necessarily. Maybe something knocked it out of its regular orbit and it's spiraling into the star. Maybe we're just witnessing its death.
Why do you think physicists need to visit a planet to be able to make reliable measurements about them? I would expect that they can have confidence in their measuring equipment in the same way that you can have confidence that the sun will rise in the morning. After all, you have never been there, how can you know anything about how it works?
perhaps it's spiraling to its demise after billions of years in a decaying orbit.
Interesting how in the article, they never use the word "impossible". Infact, they actually put forward a handful of possible (although unlikely)ways that this may have occurred.
There's bazillions of things that are unlikely to happen, but the universe is a big place. While we can't predict which particular weird thing we might observe next time, we shouldn't be all that surprised that weirdness is out there.
One time I threw a brick at a duck.
That would fall under "our understanding of orbital dynamics is wrong".
No kidding!!! What do you say at this point?
Perhaps instead of a hot Jupiter what they have found is a cold sun?
This is the problem with science journalism...it tries to jazz up stories to make them more interesting to the layperson, but in the process ends up making scientists look like idiots. I seriously doubt these astrophysicists discovered this planet and immediately ran to the nearest reporter, and breathlessly declared that 400 years of accumulated knowledge in orbital dynamics is wrong because they just discovered an "impossible" planet.
What probably happened is something more like this:
An astrophysicist and a journalist sit at a bar after a long day's work looking through telescopes/making shit up.
Journalist: Anything interesting happen today?
Astrophysicist: Actually, yes. We discovered a planet orbiting around another star.
Journalist: Another one? I said interesting, not yet another stupid gas-ball orbiting around another star...that's page H12 at best.
Astrophysicist: Well, the funny thing is, this star is orbiting closer to its star than it ought to be able to...so it's kind of weird.
Journalist: (rolling eyes) So what?
Astrophysicist: The orbit its in should be unstable...it should eventually fall into the star and burn up.
Journalist: Okay, so we have some planet that might be about to burn up...okay, we're probably page 5C with that one.
Astrophysicist: Sure, that's probably what will happen. Of course, if the orbit its in is somehow stable, which is impossible, that would mean 400 years of understanding in orbital dynamics is wrong...(chuckles)...but of course that's ridiculous.
Journalist: 400 years of physics wrong? Impossible planet? I smell a Pulitzer! To the presses!
Astrophysicist: Hey, wait! Come back! That's not what I said...Oh well, at least I can use his article in my next grant application.
Aaaaaand...scene!
Absolutely. However, scientists get nervous when they see something this unlikely, especially with such a small sample of similar systems to date. Often, such weirdness means something else is going on that we didn't consider, so the nervousness is justifiable in the general case.
Actually, I thought about your point when the show aired. In fact, it is impossible for that planet to exist. You can't form a long-term stable orbit around a black hole. From a two-body, Newtonian point-mass analysis, yes the planet can exist. However, a planet that close to a black hole will be affected by Einstein's General Relativity, which predicts a collapsing orbit. Additionally, the planet would be experiencing severe gravitational stresses and magnetic stresses, causing it to break up or its orbit to decay. The other matter collapsing into the black hole would disrupt the "stable" orbit, also causing the planet's orbit to decay or it to break up. In short, I don't think that it is possible to have a long-term stable orbit around an black hole when it is consuming matter.
If you want a bigger plot "hole", think about where the magic gravity beam came from. Why would it come from a black hole? If it came from the planet, then why was it pointed in space? If the evil creature could create a gravity beam big enough to save a planet, then why couldn't he make a slightly bigger one and take over the universe? Maybe, we need to accept that any Sci-Fi plot will have its weak points, and suspend our disbelief.
The Satan Pit / Impossible Pit were really great Doctor Who episodes. Maybe we should appreciate them for that, instead of taking apart the physics?
It's almost certain that the journalists never talked to the scientists at all... Nature comes out weekly and there is an embargoed press release that is sent out to media outlets with a short synopsis/blurb of this weeks articles. Science journalists look it over and see whether there is anything particularly cool for the science section this week (i.e. nothing too abstract like particle physics) and then write up something quick for that weeks science section often just based on the press release (they may or may not read the actual article, which are often aimed at specialists and can be a difficult read at times). Longer form articles in the week-end paper usually include actually contacting the guys who did the study, but if there is no direct quote from the actual scientist who wrote the paper in the newspaper story then chances are high there was no scientist-journalist contact at all, and chances are almost as high that the journalist did not read the actual study, just the press release from Nature (after all the study was just published today).
...there's only a 1 in 1000 chance it would be observable now. We've found less than 1000 exoplanets, so the math doesn't work.
That's not how it works. Suppose I pick a number between 1 and 1000 at random. Then, suppose I roll a 1000 sided die. Odds are 1 in 1000 that those numbers will match, but that doesn't mean I can't roll the die and match those two numbers with less than 1000 throws. I might match the numbers on the very first throw! It just means I probably shouldn't bet my retirement on matching those numbers on any given throw.
Similarly, if the odds of discovering a planet such as Wasp18b are 1 in 1000, that doesn't mean that, "we've found less than 1000 planets, so we couldn't possibly have found such a planet yet." It just means that if I observe 1000 planets, most likely only one of them will be like Wasp18b. It could be the first one I observe, the 99th, the 1000th or any one in between.
MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?