Jump to content
  • entries
    188
  • comments
    492
  • views
    70,879

NASA Press Conference


Letagi

1,109 views

 Share

That was slightly underwhelming, but cool nonetheless.

 

The new Kepler discovery was exactly what I and most others expected it to be - the most habitable exoplanet found to date, but with no signs of life.

 

The planet, Kepler-452b, is the only planet found so far in the Kepler-452 system, 1400 light years from Earth. It was discovered using the transit method, where the apparent brightness of a distant star decreases slightly (usually by about one part in 10,000) when an orbiting planet passes between it and Earth. If this happens at regular intervals, then further methods of analysis are used to determine whether it is in fact a planet (since the same effect can be caused by binary star systems and other phenomena).

 

Kepler-452b has a mass of 5±2 Earth masses, a radius 60% larger than Earth and a corresponding surface gravity of about 2g (with an error margin related to the error margins for mass and size, but I'm too lazy to calculate that). Its orbit is 5% larger in radius than that of Earth and lasts 385 Earth days, but its star is older and thus more active, and so the planet receives 10% more solar radiation than Earth. This would cause an Earth-size planet at the same location to be undergoing a runaway greenhouse effect, similar to Venus, but Kepler-452b's larger mass means that won't happen for another 500 million years or so (if our observations are correct; there's a possibility we're slightly off somewhere, and it is indeed happening now).

 

Currently, the technology for analysis of atmospheric composition of exoplanets doesn't exist. It's not beyond our current capabilities - we just haven't built a big enough telescope yet. Thus, we have no idea what the atmosphere of Kepler-452b is made of. If future findings show it to have dioxygen and/or methane in significant quantities, it will be an excellent candidate for life as we know it.

 

-Letagi

  • Upvote 3
 Share

6 Comments


Recommended Comments

 

 

Currently, the technology for analysis of atmospheric composition of exoplanets doesn't exist. It's not beyond our current capabilities - we just haven't built a big enough telescope yet.

Read: Seriously guys give NASA money

  • Upvote 2
Link to comment

 

 

 

Currently, the technology for analysis of atmospheric composition of exoplanets doesn't exist. It's not beyond our current capabilities - we just haven't built a big enough telescope yet.

Read: Seriously guys give NASA money

 

The Extremely Large Telescope (39.3-metre-diameter primary mirror) will be big enough to image exoplanets and analyze their atmospheres, but it's not a NASA venture. It will be built by the European Southern Observatory, to be finished in 2024.

 

And yes, they're actually calling it the Extremely Large Telescope. We physicists aren't known for coming up with imaginative names; we use up all our imagination doing science. :P

 

All that said though, NASA could definitely use more money. Their annual budget is only around 0.5% of the total US federal budget.

 

-L

  • Upvote 3
Link to comment

What I really hope NASA does is one of those distributed lens designs like in the book Blue Remembered Earth where you have a whole bunch of satellites that all photograph the same star at the same moment and then build a hi-res picture.

  • Upvote 2
Link to comment

Those are already in use, but they're ground-based. I'm not sure if NASA owns or operates any of them, but there are fields of radio telescopes that all work together. They do the same thing with larger optical telescopes; there's a project going on right now that aims to directly image Sagittarius A* (the black hole at the centre of the Milky Way) which involves several major telescopes around the world. There's also a project in the beginning stages called the Colossus Telescope, which is an array of 60 eight-metre telescopes that together yield a 74-metre effective resolution.

 

-L

Link to comment
Guest
Add a comment...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...