Kepler-452b Kepler Announcement 23 July

[Kryten]

It's 5 earth masses plus or minus 2. It's likely not even rocky.

[Glaran K'erman]

Shoulda figured I'd be ninja'd like a million times by now on this board...my bad.

Edit: By the way where are you getting that info Kryten, just curious?

[NFUN]

Shoulda figured I'd be ninja'd like a million times by now on this board...my bad.

Edit: By the way where are you getting that info Kryten' date=' just curious?[/quote']

The conference had the information on its mass, as did the articles published about it. Kryten is just assuming that it wouldn't be rocky, but we don't know yet. It could be Earth-like, or even a water world.

[Frida Space]

Or maybe we are Kepler-452b 2.0?

[NFUN]

Citation Needed.

Wikipedia has citations. He linked to Wikipedia. Therefore he linked to citations. QED.

[Godot]

Jep ... and the original source for all this obviously is the paper by Jenkins et al. (2015)

https://www.nasa.gov/sites/default/files/atoms/files/ms-r1b.pdf

Addendum:

This only goes for the physical characteristics of Kepler 452b ... the paper doesn´t seem to calculater the ESI as well

Edited July 24, 2015 by Godot

[Glaran K'erman]

Indeed NFUN, as I was thinking as well.

[megatiger78]

I suggest we crash Pluto into it. to deal wit h the pulto debate, and get rid of xenos.

[KerikBalm]

Based on Mass, proportionately, its closer to Uranus than Earth is to it.

Assume it is 5 Earth masses.

Then Earth is 0.2x the mass of this planet.

This planet is 0.345x the mass of Uranus.

Anyone care to calculate the escape velocity for this thing? I'm going to guess its enough for it to retain at least helium, if not hydrogen.

[AngelLestat]

Think you could see the wobble on the sides not forward and back.

And the Jupiter around Alpha centaury was just something I read about that if Pandora in avatar was plausible.

Wikipedia also says a bit that large planets would have been detected.

Yeah but it will be very small at that angle.

But well, now that I remember, the closest approach from alpha centauri A to B is 11 Au, this mean that stable orbits are inside the 3 Au for "A" and 2 Au for "B".

Jupiter is at 5 au from our sun. But well, it may be a gas giant or at least one neptune at 3 au or even close.

Here they talk about the possible planets around "B" using the wobble method, but of course, they are earth size planets at distances where their orbit period is few days for one, and 20 days for the other.

https://www.newscientist.com/article/dn27259-twin-earths-may-lurk-in-our-nearest-star-system/

[Exclipse]

It is also orbiting closer to the inside of the hab zone of it's star, more like a fat Venus?

[Vanamonde]

Merged into the existing thread for this subject. Also, the title of this thread will be edited in hopes of avoiding more duplication.

[Frida Space]

[Mitchz95]

The Habitable Exoplanets Catalog lists it as #6, with an ESI of 0.83.

[cryogen]

The Habitable Exoplanets Catalog lists it as #6, with an ESI of 0.83.

Just to be clear, there's exactly two numbers going into that calculation: the diameter and the orbit period. That's it; that's all the data we have.

It's easy to overinterpret these two numbers, when they're hyped up in this crazy way.

The other numbers are pure guesses. The density is a generic figure for rocky planets; the mass and surface gravity are derived from that (+ measured diameter) The temperature is a WAG. It's a simple toy radiative balance, like this one:

https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law#Temperature_of_the_Earth

No atmosphere is guessed at. We have no knowledge about the surface albedo, so that's a WAG as well (arbitrarily set equal to earth's albedo, 0.3).

Fun fact: if you calculate the ESI of Venus, using only the data available for 452b, the figure's about 0.95 (since all the knowledge about the greenhouse gets discarded). You can easily calculate this,

http://phl.upr.edu/projects/earth-similarity-index-esi

Edited July 29, 2015 by cryogen

[lajoswinkler]

This is obviously an attempt at making this NASA's department more popular, to get more budget. It really isn't a discovery worth of such public popularity. What New Horizons is doing is way more important.