TrES-2b

Last updated
TrES-2b / Kepler-1b
Exoplanet Comparison TrES-2 b.png
Size comparison of TrES-2b with Jupiter
Discovery [1]
Discovered by O'Donovan et al.
Discovery site California & Arizona, USA
Discovery dateAugust 21, 2006
confirmed September 8, 2006
Transit
Orbital characteristics
0.03556±0.00075 AU
Eccentricity 0
2.47063±0.00001 d
Inclination 83.62±0.14 [2]
Star GSC 03549-02811 A [2]
Physical characteristics
Mean radius
1.272±0.041 [2] RJ
Mass 1.199±0.052 [2] MJ
3.284±0.016 [2] g
Albedo 0.0136
Temperature 1885+51
66
K. [3]

    TrES-2b ( Kepler-1b) is an extrasolar planet orbiting the star GSC 03549-02811 located 750 light years away from the Solar System. The planet was identified in 2011 as the darkest known exoplanet, reflecting less than 1% of any light that hits it. Reflecting less light than charcoal, on the surface the planet is said to be pitch black. [4] The planet's mass and radius indicate that it is a gas giant with a bulk composition similar to that of Jupiter. Unlike Jupiter, but similar to many planets detected around other stars, TrES-2b is located very close to its star and belongs to the class of planets known as hot Jupiters. This system was within the field of view of the Kepler spacecraft. [1]

    Contents

    This planet continues to be studied by other projects, and the parameters are continuously improving. A 2007 study improved stellar and planetary parameters. [5] A 2008 study concluded that the TrES-2 system is a binary star system. This significantly affects the values for the stellar and the planetary parameters. [2]

    Discovery

    The radial velocity of GSC 03549-02811 over time, caused by the presence of TrES-2 b. TrES-2 b rv.svg
    The radial velocity of GSC 03549–02811 over time, caused by the presence of TrES-2 b.

    TrES-2b was discovered on August 21, 2006 by the Trans-Atlantic Exoplanet Survey (TrES) by detecting the transit of the planet across its parent star using Sleuth (Palomar Observatory, California) and PSST (Lowell Observatory, Arizona), part of the TrES network of 10–cm telescopes. The discovery was confirmed by the W. M. Keck Observatory on September 8, 2006, by measuring the radial velocity of the star that hosts TrES-2b. [1]

    Spin-orbit angle

    In August 2008 more details of the relationship between the parent star and the orbit of the planet were published. The orbit was determined to be tilted by −9±12° from the stellar equator. The orbital direction was determined to be in the same direction as the star's rotation (prograde). [6]

    Kepler mission

    NASA launched Kepler in March 2009. The spacecraft is dedicated to the discovery of extrasolar planets by the transit method from solar orbit. In April 2009 the project released the first light images from the spacecraft, and TrES-2b was one of two objects highlighted in these images. Although TrES-2b is not the only known exoplanet in the field of view of this spacecraft it is the only one identified in the first light images. This object is important for calibration and check-out. [7]

    The GSC 03549-02811 system as seen from the Kepler spacecraft. (Celestial north is toward the lower left corner and the subject is in the center of the photograph as seen clearly in the enlarged view.) Kepler First Light Detail TrES-2.jpg
    The GSC 03549-02811 system as seen from the Kepler spacecraft. (Celestial north is toward the lower left corner and the subject is in the center of the photograph as seen clearly in the enlarged view.)

    The Kepler mission also managed to detect the mass of the planet from Kepler data alone through the analysis of the light curve of the host star. In addition to detecting the planet directly, the planet was also detected by analysis of the star brightness caused by the gravitational tug of TrES-2b by shape distortion of the host star and by light variations due to Doppler beaming. [8]

    Physical characteristics

    Albedo

    An artist's impression of TrES-2b Jkv.TrES-2b.png
    An artist's impression of TrES-2b

    The first important result from the Kepler Mission about TrES-2b is an extremely low geometric albedo measured in 2011, making it the darkest known exoplanet. [4] If the entire day–night contrast were due to geometric albedo, it would be 2.53%, but modeling suggests that much of this is dayside emission and the true albedo is much lower. It is estimated to be less than 1% and for best-fit model it is about 0.04%. This makes TrES-2b the darkest known exoplanet, reflecting less light than coal or black acrylic paint. [9] It is not clear why the planet is so dark. One reason could be an absence of reflective clouds such as those which make Jupiter so bright, due to TrES-2b's proximity to its parent star and the consequent high temperature. Another reason could be the presence in the atmosphere of light-absorbing chemicals such as vaporized sodium, potassium, or gaseous titanium oxide; [10] however, Kipping and Spiegel excluded heavy oxides of titanium and vanadium from their models, as it seems unrealistic that condensed, heavy compounds be present in the upper atmosphere. They also note that in general, hot Jupiters are expected to be dark, because "absorption due to the broad wings of the sodium and potassium D lines is thought to dominate their visible spectra", and, apart from that of Kepler-7b (38±12%), albedo measurements for hot Jupiters have generally given only upper limits. [4]

    Temperature

    The planet is likely to be tidally locked to the parent star. In 2015, the planetary nightside temperature was estimated to be equal to 1885+51
    66
    K. [3]

    See also

    Related Research Articles

    <span class="mw-page-title-main">Exoplanet</span> Planet outside the Solar System

    An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of the detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. As of 1 December 2023, there are 5,550 confirmed exoplanets in 4,089 planetary systems, with 887 systems having more than one planet. The James Webb Space Telescope (JWST) is expected to discover more exoplanets, and also much more about exoplanets, including composition, environmental conditions and potential for life.

    <span class="mw-page-title-main">TrES-1b</span> Hot Jupiter orbiting TrES-1 in the constellation of Lyra

    TrES-1b is an extrasolar planet approximately 523 light-years away in the constellation of Lyra. The planet's mass and radius indicate that it is a Jovian planet with a similar bulk composition to Jupiter. Unlike Jupiter, but similar to many other planets detected around other stars, TrES-1 is located very close to its star, and belongs to the class of planets known as hot Jupiters. The planet was discovered orbiting around GSC 02652-01324.

    <span class="mw-page-title-main">Hot Jupiter</span> Class of high mass planets orbiting close to a star

    Hot Jupiters are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods. The close proximity to their stars and high surface-atmosphere temperatures resulted in their informal name "hot Jupiters".

    The Trans-Atlantic Exoplanet Survey, or TrES, used three 4-inch (10 cm) telescopes located at Lowell Observatory, Palomar Observatory, and Teide Observatory to locate exoplanets. It was made using the network of small, relatively inexpensive telescopes designed to look specifically for planets orbiting bright stars using the transit method. The array used 4-inch Schmidt telescopes having CCD cameras and automated search routines. The survey was created by David Charbonneau of the Center for Astrophysics, Timothy Brown of the National Center for Atmospheric Research, and Edward Dunham of Lowell Observatory.

    <span class="mw-page-title-main">Methods of detecting exoplanets</span>

    Any planet is an extremely faint light source compared to its parent star. For example, a star like the Sun is about a billion times as bright as the reflected light from any of the planets orbiting it. In addition to the intrinsic difficulty of detecting such a faint light source, the light from the parent star causes a glare that washes it out. For those reasons, very few of the exoplanets reported as of April 2014 have been observed directly, with even fewer being resolved from their host star.

    <span class="mw-page-title-main">WASP-2b</span> Extrasolar planet in the constellation Delphinus

    WASP-2b is an extrasolar planet orbiting the star WASP-2 located about 500 light years away in the constellation of Delphinus. It was discovered via the transit method, and then follow up measurements using the radial velocity method confirmed that WASP-2b was a planet. The planet's mass and radius indicate that it is a gas giant with a similar bulk composition to Jupiter. Unlike Jupiter, but similar to many other planets detected around other stars, WASP-2b is located very close to its star, and belongs to the class of planets known as hot Jupiters. A 2008 study concluded that the WASP-2b system is a binary star system allowing even more accurate determination of stellar and planetary parameters.

    HD 147506, also known as HAT-P-2 and formally named Hunor, is a magnitude 8.7 F8 dwarf star that is somewhat larger and hotter than the Sun. The star is approximately 419 light-years from Earth and is positioned near the keystone of Hercules. It is estimated to be 2 to 3 billion years old, towards the end of its main sequence life. There is one known transiting exoplanet, and a second planet not observed to transit.

    <span class="mw-page-title-main">TrES-3b</span>

    TrES-3b is an extrasolar planet orbiting the star GSC 03089-00929. It has an orbital period of just 31 hours and nearly twice the mass of Jupiter.

    <span class="mw-page-title-main">TrES-4b</span> Super Jupiter orbiting TrES-4

    TrES-4b is an extrasolar planet, and one of the largest exoplanets ever found, after WASP-12b, WASP-17b, CT Chamaeleontis b, GQ Lupi b and HD 100546 b. It was discovered in 2006, and announced in 2007, by the Trans-Atlantic Exoplanet Survey, using the transit method. It is approximately 1,400 light-years (430 pc) away orbiting the star GSC 02620-00648, in the constellation Hercules.

    This page describes exoplanet orbital and physical parameters.

    <span class="mw-page-title-main">HAT-P-7b</span> Super Jupiter orbiting HAT-P-7

    HAT-P-7b is an extrasolar planet discovered in 2008. It orbits very close to its host star and is larger and more massive than Jupiter. Due to the extreme heat that it receives from its star, the dayside temperature is predicted to be 2,630–2,880 K K, while nightside temperatures are 2,211–2,238 K. HAT-P-7b is also one of the darkest planets ever observed, with an albedo of less than 0.03—meaning it absorbs more than 97% of the visible light that strikes it.

    <span class="mw-page-title-main">GSC 03549-02811</span> Main sequence - star in the constellation Draco

    GSC 03549-02811 is a yellow main-sequence star similar to the Sun. This star is located approximately 704 light-years away in the constellation of Draco. The apparent magnitude of this star is 11.41, which means it is not visible to the naked eye but can be seen with a medium-sized amateur telescope on a clear dark night. The age of this star is about 5 billion years.

    <span class="mw-page-title-main">Kepler-7b</span> Hot Jupiter orbiting Kepler-7

    Kepler-7b is one of the first five exoplanets to be confirmed by NASA's Kepler spacecraft, and was confirmed in the first 33.5 days of Kepler's science operations. It orbits a star slightly hotter and significantly larger than the Sun that is expected to soon reach the end of the main sequence. Kepler-7b is a hot Jupiter that is about half the mass of Jupiter, but is nearly 1.5 times its size; at the time of its discovery, Kepler-7b was the second most diffuse planet known, surpassed only by WASP-17b. It orbits its host star every five days at a distance of approximately 0,06 AU. Kepler-7b was announced at a meeting of the American Astronomical Society on January 4, 2010. It is the first extrasolar planet to have a crude map of cloud coverage.

    <span class="mw-page-title-main">Kepler-8b</span> Extrasolar planet

    Kepler-8b is the fifth of the first five exoplanets discovered by NASA's Kepler spacecraft, which aims to discover planets in a region of the sky between the constellations Lyra and Cygnus that transit their host stars. The planet is the hottest of the five. Kepler-8b was the only planet discovered in Kepler-8's orbit, and is larger than Jupiter. It orbits its host star every 3.5 days. The planet also demonstrates the Rossiter–McLaughlin effect, where the planet's orbit affects the redshifting of the spectrum of the host star. Kepler-8b was announced to the public on January 4, 2010 at a conference in Washington, D.C. after radial velocity measurements conducted at the W.M. Keck Observatory confirmed its detection by Kepler.

    <span class="mw-page-title-main">Discoveries of exoplanets</span> Detecting planets located outside the Solar System

    An exoplanet is a planet located outside the Solar System. The first evidence of an exoplanet was noted as early as 1917, but was not recognized as such until 2016; no planet discovery has yet come from that evidence. What turned out to be the first detection of an exoplanet was published among a list of possible candidates in 1988, though not confirmed until 2003. The first confirmed detection came in 1992, with the discovery of terrestrial-mass planets orbiting the pulsar PSR B1257+12. The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi. Some exoplanets have been imaged directly by telescopes, but the vast majority have been detected through indirect methods, such as the transit method and the radial-velocity method. As of 1 December 2023, there are 5,550 confirmed exoplanets in 4,089 planetary systems, with 887 systems having more than one planet. This is a list of the most notable discoveries.

    <span class="mw-page-title-main">Kepler-11</span> Sun-like star in the constellation Cygnus

    Kepler-11, also designated as 2MASS J19482762+4154328, is a Sun-like star slightly larger than the Sun in the constellation Cygnus, located some 2,150 light years from Earth. It is located within the field of vision of the Kepler spacecraft, the satellite that NASA's Kepler Mission uses to detect planets that may be transiting their stars. Announced on February 2, 2011, the star system is among the most compact and flattest systems yet discovered. It is the first discovered case of a star system with six transiting planets. All discovered planets are larger than Earth, with the larger ones being about Neptune's size.

    <span class="mw-page-title-main">Kepler-42</span> Red dwarf star in the constellation Cygnus

    Kepler-42, formerly known as KOI-961, is a red dwarf located in the constellation Cygnus and approximately 131 light years from the Sun. It has three known extrasolar planets, all of which are smaller than Earth in radius, and likely also in mass.

    <span class="mw-page-title-main">Kepler-69c</span> Super-Earth orbiting Kepler-69

    Kepler-69c is a confirmed super-Earth extrasolar planet, likely rocky, orbiting the Sun-like star Kepler-69, the outermore of two such planets discovered by NASA's Kepler spacecraft. It is located about 2,430 light-years from Earth.

    <span class="mw-page-title-main">Kepler-438b</span> Super-Earth orbiting Kepler-438

    Kepler-438b is a confirmed near-Earth-sized exoplanet. It is likely rocky. It orbits on the inner edge of the habitable zone of a red dwarf, Kepler-438, about 472.9 light-years from Earth in the constellation Lyra. It receives 1.4 times our solar flux. The planet was discovered by NASA's Kepler spacecraft using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. NASA announced the confirmation of the exoplanet on 6 January 2015.

    Kepler-13 or KOI-13 is a stellar triple star system consisting of Kepler-13A, around which an orbiting hot Jupiter exoplanet was discovered with the Kepler spacecraft in 2011, and Kepler-13B a common proper motion companion star which has an additional star orbiting it.

    References

    1. 1 2 3 O'Donovan, Francis T.; et al. (2006). "TrES-2: The First Transiting Planet in the Kepler Field". The Astrophysical Journal Letters. 651 (1): L61–L64. arXiv: astro-ph/0609335 . Bibcode: 2006ApJ...651L..61O . doi: 10.1086/509123 .
    2. 1 2 3 4 5 6 Daemgen, S.; Hormuth, F.; Brandner, W.; Bergfors, C.; Janson, M.; Hippler, S.; Henning, T. (2009). "Binarity of transit host stars — Implications for planetary parameters" (PDF). Astronomy and Astrophysics . 498 (2): 567–574. arXiv: 0902.2179 . Bibcode:2009A&A...498..567D. doi:10.1051/0004-6361/200810988. S2CID   9893376.
    3. 1 2 A Comprehensive Study of Kepler Phase Curves and Secondary Eclipses:Temperatures and Albedos of Confirmed Kepler Giant Planets
    4. 1 2 3 David M. Kipping & David S. Spiegel (2011). "Detection of visible light from the darkest world" (PDF). Monthly Notices of the Royal Astronomical Society . 417 (1): L88. arXiv: 1108.2297 . Bibcode:2011MNRAS.417L..88K. doi:10.1111/j.1745-3933.2011.01127.x. S2CID   119287494. Archived from the original on March 17, 2012. Retrieved 2011-08-12.{{cite journal}}: CS1 maint: unfit URL (link)
    5. Alessandro Sozzetti; Torres, Guillermo; Charbonneau, David; Latham, David W.; Holman, Matthew J.; Winn, Joshua N.; Laird, John B.; o’Donovan, Francis T. (August 1, 2007). "Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2". The Astrophysical Journal. 664 (2): 1190–1198. arXiv: 0704.2938 . Bibcode:2007ApJ...664.1190S. doi:10.1086/519214. S2CID   17078552.
    6. Winn, Joshua N.; Johnson, John Asher; Narita, Norio; Suto, Yasushi; Turner, Edwin L.; Fischer, Debra A.; Butler, R. Paul; Vogt, Steven S.; et al. (2008). "The Prograde Orbit of Exoplanet TrES-2b". The Astrophysical Journal. 682 (2): 1283–1288. arXiv: 0804.2259 . Bibcode:2008ApJ...682.1283W. doi:10.1086/589235. S2CID   14857922.
    7. "Kepler Eyes Cluster and Known Planet". NASA. 2009-04-16. Retrieved 2009-05-09.
    8. Photometrically derived masses and radii of the planet and star in the TrES-2 system: Thomas Barclay, Daniel Huber, Jason F. Rowe, Jonathan J. Fortney, Caroline V. Morley, Elisa V. Quintana, Daniel C. Fabrycky, Geert Barentsen, Steven Bloemen, Jessie L. Christiansen, Brice-Olivier Demory, Benjamin J. Fulton, Jon M. Jenkins, Fergal Mullally, Darin Ragozzine, Shaun E. Seader, Avi Shporer, Peter Tenenbaum, Susan E. Thompson
    9. Charles Q. Choi (2011-08-11). "Coal-Black Alien Planet Is Darkest Ever Seen". Space.com. Archived from the original on 2012-06-24. Retrieved 2014-12-26.
    10. Baldwin, Emily (2011-08-11). "Exoplanet blacker than coal". Astronomy Now. Archived from the original on 2011-09-18. Retrieved 2011-08-12.