PH2

{{About|the star|other uses|Ph2 (disambiguation){{!}}Ph2}}

{{starbox begin

| name = PH2 / Kepler-86

}}

{{starbox image

| image = 250px

| caption = Artist's conception of PH2 and its planet, PH2b, viewed from a hypothetical moon of the planet.

| credit = Haven Giguere, Matthew Giguere/Yale

}}

{{Starbox observe

| epoch = J2000

| constell = Cygnus

| ra = {{RA|19|19|03.26334}}

| dec = {{dec|+51|57|45.4099}}

| appmag_v = {{val|12.699|0.010}}

}}

{{Starbox character

| type = Main sequence

| class = F9

| appmag_1_passband = J

| appmag_1 = {{val|11.501|0.023}}

| appmag_2_passband = H

| appmag_2 = {{val|11.182|0.03}}

| appmag_3_passband = K

| appmag_3 = {{val|11.116|0.022}}

| appmag_4_passband = B1

| appmag_4 = 12.34

| appmag_5_passband = R1

| appmag_5 = 12.62

| r-i =

| v-r =

| b-v = 0.072

| u-b =

| j-h =

| j-k =

| variable =

}}

{{Starbox astrometry

| radial_v = {{val|-17.79|1.88}}

| prop_mo_ra = {{val|3.427}}

| prop_mo_dec = {{val|16.047}}

| pm_footnote =

| parallax = 2.9134

| p_error = 0.0105

| parallax_footnote =

| absmag_v =

| absmag_bol = {{val|5.01|+0.12|-0.12}}Calculated based on -2.5 log₁₀ of luminosity differences.

}}

{{Starbox detail

| source =

| mass = {{val|0.958|0.034}}

| radius = {{val|0.961|0.016|0.015}}

| luminosity_bolometric = {{val|0.79|0.09|0.08}}

| gravity = {{val|4.45|0.02}}

| temperature = {{val|5711|60|59}}

| metal_fe = {{val|-0.03|0.04}}

| rotation = 22.6 days

| rotational_velocity = {{val|1.43|0.78}}

| age_gyr =

}}

{{Starbox catalog

| names = {{odlist | name=PH2 | 2MASS=J19190326+5157453 | Kepler=86 | KIC=12735740 | KOI=3663 | TIC=416279912}}

}}

{{starbox reference

| KIC = 12735740

| Simbad = KIC+12735740

}}

PH2, also known as Kepler-86, or KIC 12735740 (2MASS J19190326+5157453), is an F-type main-sequence star {{convert|1120|ly|pc|lk=on|abbr=off}} distant within the constellation Cygnus. Roughly the size and temperature of the Sun, PH2 gained prominence when it was known to be the host of one of 42 planet candidates detected by the Planet Hunters citizen science project in its second data release. The candidate orbiting around PH2, known as PH2b, had been determined to have a spurious detection probability of only 0.08%, thus effectively confirming its existence as a planet.

Located in its parent star's habitable zone, PH2b (or Kepler-86b) is a Jupiter-size gas giant which could in theory host a natural satellite suitable for hosting life. The report of the confirmed detection of PH2b was submitted on January 3, 2013. It was discovered by amateur Pole Rafał Herszkowicz using his laptop and access to the Internet project with data from the Kepler space observatory.{{cite web|url=http://forsal.pl/artykuly/693169,polski_informatyk_rafal_herszkowicz_odkryl_nowa_planete_ph2b.html |title=Polski informatyk Rafał Herszkowicz odkrył nową planete PH2b | Forsal.pl - Giełda, Waluty, Finanse |publisher=Forsal |date=2013-03-27 |access-date=2013-07-12 |language=pl}}

History of detection

Image:LombergA1024.jpg.]]PH2 b was detected, along with 42 other planet candidates, in archival data from Kepler by the Planet Hunters project, in which human volunteers analyze the light curves of Kepler target stars, searching for planetary transit signals which may be missed by computer programs. Previous work by Planet Hunters helped to confirm the existence of PH1b, a Neptune-mass planet within a four-star system.

All of the candidates in the study, including PH2b, were identified by citizen scientists Abe J. Hoekstra, Thomas Lee Jacobs, Daryll LaCourse, Hans Martin Schwengler, Rafał Herszkowicz and Mike Chopin among others, with the help of Yale University astronomers. In addition to PH2b itself, twenty other planet candidates were found which are located in the habitable zones of their host stars; however, these have a relatively high probability of spurious detection and may well come from non-planetary sources.

Although the planet's initial detection was made using Kepler data, PH2's stellar spectra, required to rule out background stars or faint companions with planets as sources for the observed transits, were collected using the HIRES instrument at the W. M. Keck Observatory. Results of observations confirmed the existence of PH2b with "99.9 percent confidence."

Planetary system

PH2 is host to one confirmed planet, PH2b, orbiting with a period of about 282 days, placing it and any possible moons in the habitable zone. The temperature in the upper atmosphere of the planet could range from {{convert|185|K|C F}} to {{convert|303|K|C F}}. A moon of PH2b would likely have "a rocky core, plus a greenhouse atmosphere of some sort that could have liquid water on its surface" in the words of the researchers, thus further improving its prospects for habitability.

In 2019, the mass of the planet was measured by radial velocity, showing it to be close in mass to Saturn.

{{OrbitboxPlanet begin

| table_ref =

}}

{{OrbitboxPlanet

| exoplanet = b

| mass_earth = {{val|108.81|29.79|32.29}}

| radius_earth = {{val|9.49|0.16}}

| semimajor = {{val|0.824|0.019|0.017}}

| period = {{val|282.52540|0.00010|0.00011}}

| eccentricity = {{val|0.280|0.121|0.133}}

| inclination = {{val|89.915|0.020|0.022}}

}}

Notes

=References=

{{reflist|refs=

{{cite journal |bibcode=2022ApJS..261...26S |title=Magnetic Activity and Physical Parameters of Exoplanet Host Stars Based on LAMOST DR7, TESS, Kepler, and K2 Surveys |last1=Su |first1=Tianhao |last2=Zhang |first2=Li-yun |last3=Long |first3=Liu |last4=Han |first4=Xianming L. |last5=Misra |first5=Prabhakar |last6=Meng |first6=Gang |last7=Pi |first7=Qingfeng |last8=Yang |first8=Zilu |last9=Yang |first9=Jiawei |journal=The Astrophysical Journal Supplement Series |date=2022 |volume=261 |issue=2 |page=26 |doi=10.3847/1538-4365/ac7151 |doi-access=free }}

{{cite web|author=Staff |title=Congratulations! MT @planethunters: Our 2nd confirmed planet PH2 b has received the alternate Kepler designation of Kepler-86b. |url=http://inagist.com/all/382705708380073984/ |date=September 25, 2013 |work=inagist/@NASAKepler |access-date=September 25, 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130927173306/http://inagist.com/all/382705708380073984/ |archive-date=September 27, 2013 }}

{{cite web|url=http://irsa.ipac.caltech.edu/workspace/TMP_7aNmhU_31885/Gator/irsa/3547/tbview.html |title=Gator Cone Search Result |publisher=NASA/IPAC |work=The Two Micron All Sky Survey at IPAC |access-date=January 12, 2013 }}{{dead link|date=May 2017 |bot=InternetArchiveBot |fix-attempted=yes }}

{{cite web | url=http://archive.stsci.edu/kepler/data_search/search.php?action=Search&ktc_kepler_id=12735740 |title=Kepler Data Search Results | publisher=Space Telescope Science Institute | work=MAST | access-date=January 12, 2013}}

{{cite web | url=http://www.pas.rochester.edu/~emamajek/sun.txt | title=Basic Astronomical Data for the Sun (BADS) | publisher=University of Rochester | date=December 30, 2012 | access-date=January 12, 2013 | author=Mamajek, Eric}}

{{cite web |url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html | title=Sun Fact Sheet | publisher=National Aeronautics and Space Administration |date=March 2, 2012 | access-date=January 12, 2013 | author=Williams, David R.}}

{{cite news |url=http://www.space.com/19233-amateurs-discover-alien-planets.html | title=Amateur Astronomers Discover 42 Alien Planets | work=Space.com |date=11 January 2013 | agency=Space.com | access-date=January 12, 2013 | author=Howell, Elizabeth}}

{{cite journal |last1=Wang |first1=Ji |last2=Fischer |first2=Debra A. |display-authors=etal |date=October 2013 |title=Planet Hunters. V. A Confirmed Jupiter-size Planet in the Habitable Zone and 42 Planet Candidates from the Kepler Archive Data |journal=The Astrophysical Journal |volume=776 |issue=1 |pages=10 |doi=10.1088/0004-637X/776/1/10 |arxiv=1301.0644 |bibcode=2013ApJ...776...10W|s2cid=119241051 }}

{{cite journal |last1=Dubber |first1=Sophie C. |last2=Mortier |first2=Annelies |display-authors=etal |date=December 2019 |title=Using HARPS-N to characterize the long-period planets in the PH-2 and Kepler-103 systems |journal=Monthly Notices of the Royal Astronomical Society |volume=490 |issue=4 |pages=5103–5121 |doi=10.1093/mnras/stz2856 |doi-access=free |arxiv=1910.03518 |bibcode=2019MNRAS.490.5103D}}

}}

=Footnotes=

External links

[https://web.archive.org/web/20131105082102/http://www.nasa.gov/mission_pages/kepler/main/index.html Kepler Mission] - NASA.
[https://archive.today/20130215193638/http://www.cthreepo.com/stars/viewK.php?KIC=12735740 KIC-12735740 Star on Star Finder/cthreepo]
[https://www.youtube.com/watch?v=qHvb9mewXJo Video (00:52) - Journey To Exoplanet "PH2 b"]

Category:F-type main-sequence stars

Category:Cygnus (constellation)

3663

J19190326+5157453

Category:Planetary transit variables

Category:Planetary systems with one confirmed planet

PH2