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Revolutionary New View of Baby Planets Forming Around a Star
astroengine writes Welcome to HL Tauri — a star system that is just being born and the target of one of the most mind-blowing astronomical observations ever made. Observed by the powerful Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, this is the most detailed view of the proto-planetary disk surrounding a young star 450 light-years away. And those concentric rings cutting through the glowing gas and dust? Those, my friends, are tracks etched out by planets being spawned inside the disk. In short, this is the mother of all embryonic star system ultrasounds. But this dazzling new observation is so much more — it's a portal into our solar system's past, showing us what our system of planets around a young sun may have looked like over 4 billion years ago. And this is awesome, because it proves that our theoretical understanding about the evolution of planetary systems is correct. However, there are some surprises. "When we first saw this image we were astounded at the spectacular level of detail," said Catherine Vlahakis, ALMA Deputy Program Scientist. "HL Tauri is no more than a million years old, yet already its disc appears to be full of forming planets. This one image alone will revolutionize theories of planet formation."
I've always wondered who does the "Artist's impression of" things for NASA and various other agencies. Do they just employ some CG artists full time and they're basically on-call to whip something up so they can actually publish one of these articles? How accurate are they or are just going for visual impact instead of real fidelity?
When you can go to the source?
No, no, you're not thinking; you're just being logical. --Niels Bohr
What is most interesting is the nearly equal radial spacing of the half dozen most distinct rings.
That begs the question, why?
I'm privileged to get to work on a prototype antenna for this project, which was just installed on Kitt Peak and commissioned today.
The determined Real Programmer can write Fortran programs in any language.
I bet I'm not the only one who'd be chuffed if Jim Blinn did a Slashdot interview.
I really wish news articles would get their terminology right.
No.
The correct term is planetary system.
But hey, at least they didn't do what so many other publications do and incorrectly refer to exoplanetary systems as "other solar systems" as though "Solar" is a generic term and not, in actuality, a proper noun referring to our sun, Sol.
Okay I'll stop being pedantic now.
But seriously, people, use the terms correctly.
You're right, I wouldn't steal a car. But if it were possible, I sure as hell would download one!
Sadly, one of them will probably be like Pluto.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
I guess it's a good thing you're not an astronomer or a cosmologist. One of the things that we've already learned from such images is that our current model of how solar systems form needs tweaking (according to our models, this star isn't old enough to have protoplanets or vote, although it can serve in the military).
...mind blowing, powerful, my friends, mother-of-all, dazzling, awesome, astounded, revolutionize...
Or is it more like something in your spam folder?
Scientists used this one weird trick to find exoplanets... And you won't BELIEVE what happened next!
#DeleteChrome
We finally know how is babby formed!
This image is utterly astonishing. When I was young, it was assumed that we would never see any other solar system as more than a point of light, or one point of light for each star in the system. Now this stunning resolution. Therefore I need to do a reality check on the resolution.
From the wikipedia page about the Chile telescope, resolution is about 10^-7 radians. From the article, distance is about 450 light-years. From the wikipedia article about light-years, one light-year is about 10^-13 kilometres. In "bc" I get this.
10^-7 * 450 * 10^13
450000000
In other words, about 450 million kilometres resolution. That's about the diameter of the orbit of Mars, I think. (I'm too lazy to look it up.) So we should be able to resolve distances equal to about the diameter of the Mars orbit. So that image must be showing orbits that go out to about Neptune, which goes at a radius of about 4500 million kilometres. Well, that kind of makes sense. But it's still utterly astonishing resolution at that distance. I wonder what they get in the 4 to 10 light-year range. And when the next telescope comes long, it will be even more breathtaking. The following is in the wikipedia article on the Chile telescope.
"Although it is designed to have a resolution 10 times greater than that of Hubble, it will be superseded in 2024 by the Square Kilometre Array in South Africa and Australia, that will have 50 times the resolution of ALMA."
"...proves that our theoretical understanding about the evolution of planetary systems is correct."
"...will revolutionize theories of planet formation."
Well, which is it? Is it proving that we're right, or proving that we've been wrong?
I expect the answer is that it confirms general aspects of the theory, but challenges specific details. As written, though, the summary seems to contradict the quote.
Bull !
Interplay with some of the close moons of Saturn: Daphnis
You're right that we're not going to be making interstellar colonies anytime soon - the only realistic option with known physics is a generation ship, and we're nowhere near experienced enough with self-contained ecosystems to build something with a decent chance of surviving the centuries or millenia an interstellar voyage would take.
Keeping people alive on the moon though? That we've got pretty well licked, so long as occasional supply runs are included in your plans. Biosphere 2 had issues, but still lasted two years as a sealed environment. Radiation shielding would complicate things, but bury it underground with natural-spectrum artificial lights and there's no reason we couldn't do at least as well on the moon, if we decided to do such a thing for some reason. Plenty of solar power available on the Peaks of Eternal Light, or we could take a compact nuclear reactor.
Where the moon would present difficulties is in growing to self-sufficiency. Not a lot of readily accessible resources there, without having ever had a water cycle there may not even be ore veins and the like. We'd pretty much need full industrial capacity to mine moon dust for raw materials before the colony could even begin to be self-sufficient - and we don't really have the technology to do that yet, to say nothing of the expense of shipping it all to the moon. Maybe an outpost could produce rocket fuel cheaply enough to drive up demand so that the profit margins would be sufficient to pay for supplies from Earth, but that's a pretty high-risk and long-term business plan. Still, it might work, and with another decade or three of unremarkable rocketry advances the shipping costs should be down to the point where you might be able to build a viable business model around it.
And then on the other side of the spectrum there's Mars - shipping costs are higher, and there's not really any promising business models I'm aware of that would make it appealing, but thanks to the plentiful CO2 and water on the doorstep a colony could conceivably supply most of the resources for growth and self-sufficiency themselves. After all CO2+water+trace elements = oxygen + food + biomass. And it's not terribly difficult to convert cellulose-rich biomass to nanocellulose - an aluminum-strong, gas-impermeable plastic that could be used for making the majority of large-scale (aka expensive to ship from Earth) equipment. And thanks to Mars' wet history we can be almost certain that there are Earthlike veins of ore in the crust, once things grow to the point that mining becomes viable.
TLDR: Earth-dependent space colonies are technically viable with today's technology - it's just the business case that doesn't (yet) make sense. Look at the ISS for evidence - its environment is far more hostile than anything on the moon or Mars, yet it has been operating continuously for over 14 years.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
" One of the things that we've already learned from such images"
TFA suggests that this is a unique image from a new telescope. Are you saying that there are others? Who is this 'we' you are referring to? You say 'according to our models'- are you saying that you are one of the scientists involved? You seem to be suggesting that I should have been able to understand all this from looking at the picture, and yet you have not said how this new image will inform myself and other slashdot readers of anything.
Have you even looked at the image or are you just copying the text of the article?
...omphaloskepsis often...
It's not realistic to expect it to throw a sodding gas giant out.
Leaving aside the fact that the executive officer for the week that stupid rule was invented is an asshat & it was never ratified by a 2/3 majority of the villagers.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Mindless troll.
We've been seeing things like protoplanetary discs since the late 1980s (Beta Pictoris, IIRC, I haven't checked it). A decade later we were seeing the protoplanetary discs distinctly from their stars. Now we're seeing multiple gaps within the discs, which allows us to do (or infer) certain Keplerian relationships about those systems.
New instruments lead to higher resolution both by direct observation and by interferometric combination of new and old instruments. And our understanding of these structures and events doesn't start from scratch, but builds on pre-existing observations and models (e.g. the Keplerian relationships I mentioned above, which are based on observations in our own stellar system).
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"