Kepler News and Results (Thread 2)

KOI-152's planets are extremely low in density. KOI-152 d specifically looks like a lower-density analogue of Kepler-87c.
http://arxiv.org/abs/1310.2642

NASAWatch: Confusion Over NASA's Policies That Ban Certain People

What a mess.

Sirius_Alpha wrote:

KOI-152's planets are extremely low in density. KOI-152 d specifically looks like a lower-density analogue of Kepler-87c.
http://arxiv.org/abs/1310.2642

http://talk.planethunters.org/discussions/DPH101z4nz

KOI-152 = Kepler-79.

They seem confirmed since aeons, but they aren't listed anywhere as such.

Low-density planets in tightly-packed systems seems to be a recurring theme.

Where are the terrestrials hiding? Detection biases or are they actually relatively rare?

Well, all of the low density planets discovered or confirmed recently have radii well over 3 earths look at kepler 20 c is dense considering its radius 3.1 earth.Hd 97658 b is smaller but significantly heavier than those planets.I would not be surprise if planets with radii less than 2 earth have similar massess like koi 152 planets.

NASAWatch: Now The Shutdown Is to Blame for Kepler Meeting Problems

Quote :

We have just learned that the efforts of NASA's Ames Research Center to ensure that our Chinese astronomer colleagues will be able to attend the Second Kepler Science Conference have been halted by the fact these approvals must be entered into a computer system at NASA HQ in Washington DC. Because of the ongoing federal government shutdown, there is no one at NASA HQ who can complete the approval process. Of course, if the federal shutdown continues much longer, the conference will not be able to begin as scheduled on November 3, 2013. We fear that the meeting may have to be cancelled as a result, or delayed. The ability of scientists to attend an open scientific meeting about the spectacular results produced by NASA's Kepler Space Telescope is another likely fatality of the failure of the U.S. Congress to enact a federal budget for FY2014. Alan Boss, SOC Co-Chair, KSC II

Isn't politics wonderful?

Kepler Finds First Signs of Other Earths

Looks like a few Earth analogues are starting to come out of the data.

[url="http://carnegiescience.edu/news/found_planets_skimming_star%E2%80%99s_surface"]Planets Skimming a Star’s Surface[/url]

On litterature: http://arxiv.org/pdf/1308.1379v1.pdf

Edited URL
 
 
Found: Planets Skimming a Star’s Surface

But "found" what? I don't think they've been confirmed. Or are they?  

No. Fourth paragraph:

Quote :

If confirmed...

Sirius_Alpha wrote:

No. Fourth paragraph:

Quote :

If confirmed...

As I thought. I don't get the reason for such press releases.

Since the false positive probability is low, and the fact that we already have an example of such a planet, it may be reasonable to state that they have been found.

Late at night here, but the media outlets reported the shutdown finally ended tonight.

So hopefully R&D can resume soon.

KOI-142 = Kepler-88.
Reference:
http://exoplanetarchive.ipac.caltech.edu/cgi-bin/DisplayOverview/nph-DisplayOverview?objname=KOI+142+b&type=CONFIRMED_PLANET

A seventh planet candidate at KOI-351.

Planet Hunters VI: The First Kepler Seven Planet Candidate System and 13 Other Planet Candidates from the Kepler Archival Data
http://arxiv.org/abs/1310.5912

Quote :

We report the discovery of 14 new transiting planet candidates in the Kepler field from the Planet Hunters citizen science program. None of these candidates overlap with Kepler Objects of Interest (KOIs), and five of the candidates were missed by the Kepler Transit Planet Search (TPS) algorithm. The new candidates have periods ranging from 124-904 days, eight residing in their host star's habitable zone (HZ) and two (now) in multiple planet systems. We report the discovery of one more addition to the six planet candidate system around KOI-351, marking the first seven planet candidate system from Kepler

Nice.I knew they will find 7 transiting planets, maybe is more(non transiting) between 9 days and 59 or beyond currently farthest in this system

A planet candidate only slightly larger than Earth in a 757-day orbit... around an A-type star! Even if it is too hot to be habitable, that's impressive if it can be confirmed.

tommi59 wrote:

Nice.I knew they will find 7 transiting planets, maybe is more(non transiting) between 9 days and 59  or beyond currently farthest  in this system

Indeed rumours are there may be and ttvs are being scrutinised, but can't say more for now.

Lazarus wrote:

A planet candidate only slightly larger than Earth in a 757-day orbit... around an A-type star! Even if it is too hot to be habitable, that's impressive if it can be confirmed.

Yeah that's one of the ones I found  , very sneaky indeed as it was hidden in poorly-calibrated data. Clear in the raw data though.

Densities and Eccentricities of 163 Kepler Planets from Transit Time Variations
http://arxiv.org/abs/1310.7942

Quote :

We extract densities and eccentricities of 163 sub-Jovian planets by analyzing transit time variations (TTVs) obtained by the {\it Kepler} mission through Quarter 12. We partially circumvent the degeneracies that plague TTV inversion with the help of an analytical formula for the TTV. From the observed TTV phases, we find that most of these planets have eccentricities of order a few percent. More precisely, the r.m.s. eccentricity is 0.018+0.004−0.008, and planets smaller than 3R⊕ are around three times as eccentric as those bigger than 3R⊕. We also find a best-fit density-radius relationship ρ≈2.2 g/cm3×(R/3R⊕)−1.8 for the 64 planets that likely have small eccentricity and hence small statistical correction to their masses. Planets larger than 3R⊕ are mostly less dense than water, implying that their radii are largely set by a massive hydrogen atmosphere.

Looks like there's several planets in the 20 - 50 Earth-mass range that have densities greater than pure iron. Chthonian planets?

Does this paper have… any detection criteria? Because there are a lot of 1σ (as in, the error is the same as the value) TTV values listed… which dutifully provide meaningless values for masses. I think that explains those rather outlandish densities.

NASA Hosts Media Briefing To Discuss Kepler Results
http://www.nasa.gov/press/2013/october/nasa-hosts-media-briefing-to-discuss-kepler-results/#.UnK5AflwqSo

Quote :

NASA will video stream a news briefing at 10:15 a.m. PST (1:15 p.m. EST) Monday, Nov. 4, to announce new results from the agency's Kepler mission. The briefing, taking place during the Kepler Science Conference, will be in building 152 at NASA Research Park in Moffett Field, Calif.

Shellface wrote:

Does this paper have… any detection criteria? Because there are a lot of 1σ (as in, the error is the same as the value) TTV values listed… which dutifully provide meaningless values for masses. I think that explains those rather outlandish densities.

Bonus points for omitting the error values from the machine-readable table.

And converting between the given nominal masses and true masses depends on the eccentricity:

Quote :

If planets in a pair have very low eccentricities (e ≪ |∆|), the nominal masses are the true masses, whereas if the eccentricities are much higher than that (e ≫ |∆|), the nominal masses are overestimates of the true masses. For intermediate eccentricities (e ~ |∆|), the nominal and true masses differ by an order unity factor—they can be either smaller or larger depending on the phase of Z_free. Note that, as shown in Section 3.1, many systems have intermediate eccentricities.

At least the planets in the high-density region of figure 3 are represented by the diamond symbols that indicate the nominal densities are overestimates of the true density.

New Kepler designation for confirmed Kepler Objects of Interests (KOIs): Kepler-89 for KOI-94 and Kepler-90 for KOI-351 systems.