Kepler News and Results

Philw note that the original plan called for weekly checks.

Hopefully they had kept to that plan and only lost a week.

2 weeks would be devastating.

Fully 5% of yearly observation time.

Keeping fingers crossed.

Theo, you are correct. It looks like something under 7 days would be the worst case loss on the safe mode event, given the weekly check schedule.

What I do not understand is how they can defer the next download to the latter part of August.

They're probably observing now.

Gather data. Transmit. Gather data. Transmit. etc.

And now onto something a bit more theoretical... paper about the detectability of exomoons by Kepler-type missions. Apparently moon masses down to 0.2 Earth masses (roughly 8 times the mass of Ganymede) could be detected around habitable zone gas giants. The best type of planets for the detection are low-density Saturn-like planets.

Whether such moons can form around planets of this type is of course another matter...

Don't know about the possibility to detect exo-planet moons but astronomers can detect if an exo-planet has a ring-system...
I believe the science community is working on higher accuracy spectrographs; 10m Keck-HIRES Hawaii-USA, 4m20 WHT LaPalma-SPAIN with HARPS-New Earth Facility trying to achieve Dopler accuracies of 0.5m/second. At the OHP, astronomers & engineers try to upgrade SOPHIE and there're even plans to re-introduce the French ELODIE spectrograph into the astro-science community

Phill (I LOVE your avatar, by the way), thanks for that info. I'm not sure that Doppler spectroscopy would be the tool to detect exoplanet moons, at least not yet. Transit timing variations (or of course the moon transiting as well) seems to be the best bet.

Exciting time we live in... Looking forward to the 400th exo-planet, what should be a nice conclusion of the International Year of Astronomy which celebrates 400 years of the Telescope
Well the latest technology try-out involves using a fangled laser comb technique with the standard Thorium/Argon reference cell.
The 1990s detectors used Hydrogen fluoride reference cells to absorb specific wavelengths of star lights, Mayor/Queloz started to use (non-poison) Thorium/Argon...

Another interesting fact I remember:
Each year the Kepler Space Telescope moves one tenth of an Astronomical Unit away from Earth on its (Earth trailing) orbit around the Sun...

Spitzer is in a similar orbit. (We're essentially making a trail of spacecrafts that will impact Earth 30 years later SL-9 style ).

Hi,
Does anybody know whether the European teams that analysed the Corot light curves will be able to participate in analysing the Kepler light curves? Or is there more of a protection of data so only US teams analysing the results?

I just wondered since I expect there to be a lot of experience gained from Corot teams.

Thanks.

Do any of the Kepler or COROT science teams have a blog? Of course they can't pre-release discoveries, but there might be usefull general insight as to how the process is going.

Dynamics of Cats usually has the inside track to these missions.

There was hint to watch for known transiting planets in the Kepler field recently.

Also mentioned was to look for earth size planets in 1 month orbits in January 2010 (edit!).

Can't hardly wait!

Great tip! I'm seting the Wayback Machine to January 1010 as we speak!

tom wrote:

Hi,
Does anybody know whether the European teams that analysed the Corot light curves will be able to participate in analysing the Kepler light curves? Or is there more of a protection of data so only US teams analysing the results?

I just wondered since I expect there to be a lot of experience gained from Corot teams.

Thanks.

I met a Researcher working on the data of COROT and I asked her the same question.

Indeed the Americans and the European are exchanged and will always be exchanged information. The Americans are more orientated to planets and European towards stars.

What is a seeker?

Excuse me, obviously my dictionary is old. I told myself well that it was not this. I think that is "Researcher".

Here's a study of 40 'nearby' M stars that concludes that Saturn-Jupiter mass planets are rare close in around M stars. 0 for 40.

paper

This indicates that Kepler won't be detecting lots of Hot Jupiters around early M stars

Well Gliese 876 does seem to be a freakishly weird system... the only strong example of close-in giant planets around M dwarfs.

(VB 10b has a mass ratio more similar to binary star systems - may well be better regarded as a low mass brown dwarf)

Kepler downloaded the science data obtained since July the 2nd. No further resets have occurred. The source of the resets seems to be the processor but the exact cause is still unknown. Next download planned for 17-18 September.

http://kepler.nasa.gov/about/manager.html

Thanx for the note on the managers update.

Here's the wiki link to the RAD750 processor.

http://en.wikipedia.org/wiki/RAD750

It is curious that there have been no further resets in over a month.

It suggests an environmental cause, radiation perhaps?

Too early to tell.

SQL-request KIC (Kepler Input Catalog)
http://whitedwarf.org/palebluedot/KIC.txt
total number of the stars - 145516

sorting on temperature:
3000-4000 Kelivinov - 2703
4000-5000 Kelivinov - 45837
5000-6000 Kelivinov - 63803
6000-7000 Kelivinov - 29249
7000-8000 Kelivinov - 2685
8000-9000 Kelivinov - 932
9000-10000 Kelivinov - 306

sorting [M/N] (estimated logarithm of heavy element abundance relative to Sun
)
-2.60 - -2.50 15
-2.50 - -2.40 36
-2.40 - -2.30 0
-2.30 - -2.20 2
-2.20 - -2.10 7
-2.10 - -2.00 24
-2.00 - -1.90 60
-1.90 - -1.80 41
-1.80 - -1.70 54
-1.70 - -1.60 59
-1.60 - -1.50 187
-1.50 - -1.40 127
-1.40 - -1.30 106
-1.30 - -1.20 159
-1.20 - -1.10 208
-1.10 - -1.00 590
-1.00 - -0.90 865
-0.90 - -0.80 1047
-0.80 - -0.70 1570
-0.70 - -0.60 3149
-0.60 - -0.50 7713
-0.50 - -0.40 10330
-0.40 - -0.30 15205
-0.30 - -0.20 21896
-0.20 - -0.10 28083
-0.10 - 0.00 24926
0.00 - 0.10 12772
0.10 - 0.20 7947
0.20 - 0.30 4261
0.30 - 0.40 1956
0.40 - 0.50 1282
0.50 - 0.60 833
0.60 - 0.70 5

sorting on brightness scale Mag
V=07.0 - 08.0 56
V=08.0 - 09.0 354
V=09.0 - 10.0 1004
V=10.0 - 11.0 2823
V=11.0 - 12.0 7189
V=12.0 - 13.0 17033
V=13.0 - 14.0 38257
V=14.0 - 15.0 78796

http://obswww.unige.ch/Instruments/harps_north/science/White_Paper.txt

Quote :

3.1 Main project goals:
Our main project has three broad scientific goals that can be achieved
by delivering planetary masses of certain precision:
(a) confirming an Earth-twin planet in the habitable zone of a G5V star
or later - 30% in mass;
(b) characterizing Earth-like planets of 2-5 M_Earth ("Super-Earths") in
different orbits: distinguishing between water-rich and dry planets - 10% in
mass;
(c) characterizing the transition between Super-Earths and Ice Giants (hot
Neptunes, for example) near 10 M_Earth - 5% in mass, or better.

For planet classes in goals (b) & (c), Kepler will determine planetary radii
of 5% or better, for stars in the "sweet spot" around V=12 mag. For the
Earth-like planets in goal (a), Kepler could provide 15% in radius precision.
All these estimates improve considerably for M-stars, but the probability
of discovery is assumed low. These values: 5% in radius, and (a),(b),& (c) in
mass, allow achieving our goals, as shown by the theoretical models
(Valencia,Sasselov,O'Connell 2006,2007; Fortney et al.2007). Note that
achieving goal (b) is essential, in a boot-strapping sense, to achieving
confidence in completing goal (a), and hence - of Kepler's legacy as whole.
HARPS-NEF in the Doppler domain is a true match to Kepler in the photometric
domain, thus providing vastly improved planetary mean densities for a
meaningful comparison to interior models.

3.2 Main project observing time requirements:
HARPS-NEF on a 4-m class telescope in the Northern hemisphere (e.g. WHT) can
achieve the above tolerances in mass determination with certain number of Doppler
measurements. That number of observations can be evaluated under the following
set of conditions. First, the Kepler light curve constrains the period and phase
of the planet's orbit. Second, we select targets of V=12 mag or brighter, for
which HARPS-NEF should achieve 1.0 m/s in 1 hour. This has been demonstrated with
the HARPS in Chile. We illustrate our estimate of required number of observations
to achieve 10% in planet mass at a 0.10 AU orbit in the table below:

Star/Planet 5 M_Earth 10 M_Earth
---------------------------------------------------
F0 (1.60 M_s) 158 40
G0 (1.05 M_s) 104 26
K0 (0.79 M_s) 78 20
M0 (0.51 M_s) 50 13
---------------------------------------------------

With such estimates in hand, we have determined the number of effective
clear observing nights (HARPS-NEF on WHT) required to accomplish the three goals
of our Main Project:
(a) for 2 planets (over 3 years) - 160 h = 16 nights per year;
(b) for 20 planets in different orbits - 250 h = 25 nights per year;
(c) for 20 planets in different orbits - 210 h = 20 nights per year.

3.3 Main project scheduling:
The 60 clear nights per year estimated above fall within the season of about
six months - April through October, when the Kepler field is accessible from
WHT. They do not have to be consecutive or time critical; queue scheduling would
work fine. We expect planets that orbit stars of different brightness and with
different periods, we can fill efficiently observing nights regardless of seeing
conditions. We anticipate having Kepler targets for goals (b) & (c) during year 1
and can begin work on them immediately - in summer 2009. For goal (a), we may have
to wait until year 3, i.e. begin in 2011, and continue until 2014.

The observing time estimates and scheduling make use of the expectation that
Kepler will provide a very large number of good targets in each of the categories
of planets. This will allow our team to select the best ones for follow-up, and
avoid parent stars that show high activity or with other problems. For example,
we estimate that about 50% of the initial targets will show intrinsic variations
which are too high for efficient HARPS-NEF follow-up.

I was wondering when a transit search mission would turn up a circumbinary planet...

Niiice!!!...

Looking at some of those light curves "WHAT is THAT?"
About that possible circumbinary planet, I'm not very convinced. The "planet"-transit signal occurs half as often as either of the stellar-transits. The binary stars appear to have a mutual period of about 4 days, but the "planet" signal occurs regularly every two days.

Though perhaps I'm not looking at it right. It seems to me to be less of a circumbinary planet, and more of a circumplanetary binary. I would reject the planet-hypothesis.

But yet I haven't a clue what could produce that little dip. With a binary orbital period of 4 days, nothing could be in a stable orbit of 2 days around anything there. (I am assuming that each little transit is made by a single object)