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Finding water anywhere is no longer a big deal. It's now known to be one of the most common substances in the universe. Hydrogen and oxygen are the first and th

by hugh3 15y ago

Finding water anywhere is no longer a big deal. It's now known to be one of the most common substances in the universe. Hydrogen and oxygen are the first and third most common elements in the universe, and forming water molecules tends to be a pretty good way for them to arrange themselves. That's not to say that it's not pretty cool to detect water vapour in a protostellar disc, just that it's not at all surprising. Another nitpick of the article: the arstechnica audience should have enough of a sense of perspective that you don't need quotes around the "only" in '"only" 175 light years away'.

Retric 15y ago
Hydrogen and Helium where generated vary soon after the big bang but oxygen is the product of stars which don't die all that fast.
- SamReidHughes 15y ago
  So are planets. Which means water is going to be fairly plentiful, relative to the amount of planetary mass we have.
  - Retric 15y ago
    Hydrogen is still a large percentage of the huge planets mass (Jupiter, Saturn, Neptune), but yea there is going to be a lot of water out there.
    - hugh3 15y ago
      Sure, but Jupiters and Saturns only form because of the heavier elements. You can't make a planet just out of hydrogen and helium (actually some models suggest you can, via some weird dynamical instability, but it's not widely believed that this is what actually happens in most cases). Instead, you form a planetary core first, out of rock and ice, and once it gets to a sufficient size (something like 20 M_earth) it's big enough to be able to hold onto hydrogen and helium, and it quickly hoovers up all the gas in its path, growing from 14 to hundreds of Earth masses in a relatively short time (less than a million years). First-generation stars are thought to be very unlikely to have planets, unless they're formed by the weird disk instability thing.
      - bediger 15y ago
        Here's a paper that seems to say that by making some reasonable assumptions about early-universe hydrodynamics, you can almost assume that life originated very early on. sdcc3.ucsd.edu/~ir118/STPA35F10/FirstLife_Sept19_JofC_arXiv.pdf That's why we see DNA fragments and possible microbial fossils in comets: DNA-based life originated well before the first planets. Weird speculation, but it does seem to hang together.
ChuckMcM 15y ago
"Finding water anywhere is no longer a big deal." Its interesting to compare this sentiment with the sentiment in the last century where the question of whether or not water was plentiful was a very real one. This is what I love about science (as opposed to dogma) which is that data can, albeit sometimes slowly, change the consensus. The notion that planets were 'common' was pure speculation, no evidence to back that up at all, but experiments like the Kepler Observatory have provided plenty of evidence that planets are quite common, even rocky ones. That Mars may have had liquid water, very controversial, now I believe pretty much everyone has bought into the notion that the 'water features' on Mars really were created by water not some other process that has the same effect as water.
- hugh3 15y ago
  Yep, that's science for you. It's an exciting time to be a planetary scientist.

by hugh3 15y ago

Retric 15y ago

Hydrogen and Helium where generated vary soon after the big bang but oxygen is the product of stars which don't die all that fast.

SamReidHughes 15y ago
So are planets. Which means water is going to be fairly plentiful, relative to the amount of planetary mass we have.
- Retric 15y ago
  Hydrogen is still a large percentage of the huge planets mass (Jupiter, Saturn, Neptune), but yea there is going to be a lot of water out there.
  - hugh3 15y ago
    Sure, but Jupiters and Saturns only form because of the heavier elements. You can't make a planet just out of hydrogen and helium (actually some models suggest you can, via some weird dynamical instability, but it's not widely believed that this is what actually happens in most cases). Instead, you form a planetary core first, out of rock and ice, and once it gets to a sufficient size (something like 20 M_earth) it's big enough to be able to hold onto hydrogen and helium, and it quickly hoovers up all the gas in its path, growing from 14 to hundreds of Earth masses in a relatively short time (less than a million years). First-generation stars are thought to be very unlikely to have planets, unless they're formed by the weird disk instability thing.
    - bediger 15y ago
      Here's a paper that seems to say that by making some reasonable assumptions about early-universe hydrodynamics, you can almost assume that life originated very early on. sdcc3.ucsd.edu/~ir118/STPA35F10/FirstLife_Sept19_JofC_arXiv.pdf That's why we see DNA fragments and possible microbial fossils in comets: DNA-based life originated well before the first planets. Weird speculation, but it does seem to hang together.

ChuckMcM 15y ago

"Finding water anywhere is no longer a big deal." Its interesting to compare this sentiment with the sentiment in the last century where the question of whether or not water was plentiful was a very real one. This is what I love about science (as opposed to dogma) which is that data can, albeit sometimes slowly, change the consensus. The notion that planets were 'common' was pure speculation, no evidence to back that up at all, but experiments like the Kepler Observatory have provided plenty of evidence that planets are quite common, even rocky ones. That Mars may have had liquid water, very controversial, now I believe pretty much everyone has bought into the notion that the 'water features' on Mars really were created by water not some other process that has the same effect as water.

hugh3 15y ago
Yep, that's science for you. It's an exciting time to be a planetary scientist.