Live data from Hacker News

Astronomers Discover Potentially Earthlike Planet Orbiting Binary Star

technologyreview.com

1–10 of 32 posts

Re: Astronomers Discover Potentially Earthlike Planet Orbiting Binary Star

#4
Sensationalist headline. Actually just a candidate for supporting liquid water (and then only for some of it's fairly elliptic orbit).

And it's pretty damn big, so not likely to be a rock, more like a gas giant (If it _doesn't _ have a large gaseous atmosphere it would I think be the biggest rock planet ever discovered.)

So "habitable exo-planet" is stretching things............... a lot.

Re: Astronomers Discover Potentially Earthlike Planet Orbiting Binary Star

#5
post #4

Sensationalist headline. Actually just a candidate for supporting liquid water (and then only for some of it's fairly elliptic orbit). And it's pretty damn big, so not likely to be a rock, more like a gas giant (If it _doesn't _ have a large gaseous atmosphere it would I think be the biggest rock planet ever discovered.) So "habitable exo-planet" is stretching things............... a lot.

This has become a common pattern with exo-planet reporting.

Often they are reported to be "earth like" or "habitable" when they only have potential for liquid water.

Also, some of these planets that are reported may not actually exits. See http://en.wikipedia.org/wiki/Gliese_581_g.

Re: Astronomers Discover Potentially Earthlike Planet Orbiting Binary Star

#6
post #5
post #4

Sensationalist headline. Actually just a candidate for supporting liquid water (and then only for some of it's fairly elliptic orbit). And it's pretty damn big, so not likely to be a rock, more like a gas giant (If it _doesn't _ have a large gaseous atmosphere it would I think be the biggest rock planet ever discovered.) So "habitable exo-planet" is stretching things............... a lot.

This has become a common pattern with exo-planet reporting. Often they are reported to be "earth like" or "habitable" when they only have potential for liquid water. Also, some of these planets that are reported may not actually exits. See http://en.wikipedia.org/wiki/Gliese_581_g .

Yeah well it's an unfortunate by-product of a) research institutions feeling the pressure to spin their output in a way which is consumer-friendly and b) the publishing industry turning that spin into an absurd attention-grabbing headline.

Re: Astronomers Discover Potentially Earthlike Planet Orbiting Binary Star

#8
A red dwarf from 1000 au would only look like a moderately bright star, won't it?

On the other hand, it would be close enough that if aliens inhabited, they could send a probe with present-day human level of technology. That is, the nearby star would serve as a stepping stone and an excuse to bridge the gap to interstellar space. Compare it to our Alpha Centauri, which lies just shy of 300K au, a relatively costly cosmic barrier to entry.

But for our neighbourhood, there is still the possibility of a brown dwarf or Jupiter-sized world lurking in the depths of our Oort cloud. Alternative destinations are 500-750au which would be good spots to place a telescope (exploiting the Sun as a gravitational lens) http://www.centauri-dreams.org/?p=10123 . You need intermediary objectives to make interstellar exploration a more realizable goal.

Re: Astronomers Discover Potentially Earthlike Planet Orbiting Binary Star

#10

In the habitable zone 74% of its orbit? Although it sounds great, I'm left skeptical: to support life, wouldn't that need to be 100%?

It doesn't need to be 100% if the atmosphere of the planet could keep enough heat for the remaining 26% of the time, which is entirely likely.

This find is awesome, but it's not what the headline describes. The planet is no "ExoEarth". It's a fantasticly cool exoplanet that could very probably support life that vaguely resembles life on Earth (not humans, though).

Post reply on HN