TOI-1338 is a

binary star system A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

located in the constellation

Pictor Pictor is a constellation in the Southern Celestial Hemisphere, located between the star Canopus and the Large Magellanic Cloud. Its name is Latin for Painting, painter, and is an abbreviation of the older name Equuleus Pictoris (the "painter's ...

, about 1,320

light-years A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

from

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

. It is orbited by two known

circumbinary planet A circumbinary planet is a planet that orbits two stars instead of one. The two stars orbit each other in a binary system, while the planet typically orbits farther from the center of the system than either of the two stars. In contrast, circums ...

s, TOI-1338 b, discovered by the

Transiting Exoplanet Survey Satellite Transiting Exoplanet Survey Satellite (TESS, Explorer 95 or MIDEX-7) is a space telescope for NASA's Explorer program, designed to search for exoplanets using the transit method in an area 400 times larger than that covered by the ''Kepler' ...

(TESS) and BEBOP-1c, discovered by the Binaries Escorted By Orbiting Planets project.

Discovery and nomenclature

The circumbinary planet TOI-1338 b was found in the summer of 2019 by Wolf Cukier, a 17-year-old attending

Scarsdale High School Scarsdale High School (SHS) is a public high school in Scarsdale, New York, United States, a coterminous town and village in Westchester County, New York. It is a part of the Scarsdale Union Free School District. The school was founded in 1917. ...

in New York at the time, who joined the

Goddard Space Flight Center The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory located approximately northeast of Washington, D.C. in Greenbelt, Maryland, United States. Established on May 1, 1959 as NASA's first space flight center, GSFC empl ...

as a summer intern. The acronym TOI stands for "TESS Objects of Interest." Cukier studied data provided by volunteers of the

Planet Hunters Planet Hunters is a citizen science project to find exoplanets using human eyes. It does this by having users analyze data from the NASA Kepler space telescope and the NASA Transiting Exoplanet Survey Satellite. It was launched by a team led by D ...

citizen science project, looking through data that had been flagged as an

eclipsing binary A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

. Cukier and six of the Planet Hunter volunteers are co-authors of the publication regarding the planet. Cukier currently attends

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

as an undergraduate student in the Department of Astrophysical Sciences and is expected to graduate in 2024. The discovery of TOI-1338 b was announced in early January 2020 at the 235th

American Astronomical Society The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the adv ...

meeting in Honolulu, Hawaii. In February 2021, a petition was launched calling for TOI-1338 b to be renamed ''SOPHIE'' in honor of late Scottish musician

Sophie Sophie is a version of the female given name Sophia, meaning "wise". People with the name Born in the Middle Ages * Sophie, Countess of Bar (c. 1004 or 1018–1093), sovereign Countess of Bar and lady of Mousson * Sophie of Thuringia, Duchess o ...

. The petition was supported by

Charli XCX Charlotte Emma Aitchison (born 2 August 1992), known professionally as Charli XCX, is an English singer and songwriter. Born in Cambridge and raised in Start Hill, Essex, she began posting songs on Myspace in 2008, which led to her discovery ...

and

Caroline Polachek Caroline Elizabeth Polachek (born June 20, 1985) is an American singer, producer and songwriter. Raised in Connecticut, Polachek co-founded the indie pop band Chairlift while studying at the University of Colorado. The duo emerged from the late- ...

. The petition was unsuccessful in renaming TOI-1338 b, however, the

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreac ...

announced that the minor planet 1980 RE1 was given the permanent name Sophiexeon in June 2021. In June 2023, a second circumbinary planet within the system was announced to have been discovered, named BEBOP-1c. It was the first circumbinary planet to be found using the

radial velocity method Doppler spectroscopy (also known as the radial-velocity method, or colloquially, the wobble method) is an indirect method for finding extrasolar planets and brown dwarfs from radial-velocity measurements via observation of Doppler shifts in t ...

The stellar binary

TOI-1338 is a single-lined

spectroscopic binary A binary star is a system of two star, stars that are gravity, gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separa ...

system, consisting of an F8 star and a

red dwarf ''Red Dwarf'' is a British science fiction comedy franchise created by Rob Grant and Doug Naylor, which primarily consists of a television sitcom that aired on BBC Two between 1988 and 1999, and on Dave since 2009, gaining a cult following. T ...

of spectral type M. The system has an age of 4.4 billion years. The two stars with masses of 1.13 and 0.313 revolve around each other every 14.6 days. The red dwarf is about nine magnitudes fainter than the primary star and cannot be detected in the

spectrum A spectrum (plural ''spectra'' or ''spectrums'') is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors i ...

. The orbit of the two stars is inclined at 89.7° and both primary and secondary

eclipse An eclipse is an astronomical event that occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three ce ...

s can be observed, although the brightness changes are very small. The primary eclipse occurs when the hotter primary star is partially occulted by the cooler secondary. It lasts about five hours and the brightness decreases by about 4%. The secondary eclipses occur when the cooler star is occulted by the hotter star. They also last about five hours but the brightness drops by less than half a percent.

Planetary system

The planet TOI-1338 b is between Neptune and Saturn in size, and has an orbit that is within ~1°

coplanar In geometry, a set of points in space are coplanar if there exists a geometric plane that contains them all. For example, three points are always coplanar, and if the points are distinct and non-collinear, the plane they determine is unique. Howe ...

with the binary. It is roughly 22 times the mass of Earth. The

spin Spin or spinning most often refers to: * Spinning (textiles), the creation of yarn or thread by twisting fibers together, traditionally by hand spinning * Spin, the rotation of an object around a central axis * Spin (propaganda), an intentionally b ...

of the primary star also aligns with the orbits of the binary and the planet ( spin-orbit angle β = °). This is the second time the

Rossiter–McLaughlin effect The Rossiter–McLaughlin effect is a spectroscopic phenomenon observed when an object moves across the face of a star. Description The Rossiter–McLaughlin effect is a spectroscopic phenomenon observed when either an eclipsing binary's second ...

was measured for a star hosting a circumbinary planet.

Kepler-16 Kepler-16 is an eclipsing binary star system in the constellation of Cygnus that was targeted by the Kepler spacecraft. Both stars are smaller than the Sun; the primary, Kepler-16A, is a K-type main-sequence star and the secondary, ...

was the first system with such a measurement. The measurement of the alignment for TOI-1338 suggests that the planet formed from a single circumbinary disk. BEBOP-1c is a

gas giant A gas giant is a giant planet composed mainly of hydrogen and helium. Gas giants are also called failed stars because they contain the same basic elements as a star. Jupiter and Saturn are the gas giants of the Solar System. The term "gas giant" ...

about 65 times the mass of Earth.

References

External links

TESS – Official WebSite

NASA Telescope Discovers Its First Planet Orbiting Two StarsTOI 1338 at ExoFOP TESSThe TOI 1338 subject at Planet Hunters, as mentioned in the paper
{{Stars of Pictor Exoplanets discovered by Planet Hunters Planetary systems with two confirmed planets 1338, TOI Pictor Eclipsing binaries F-type main-sequence stars M-type main-sequence stars

Discovery and nomenclature

The stellar binary

Planetary system

See also

References

External links