CVSO 30 (PTFO 8-8695) is a suspected binary

T Tauri T Tauri is a Trinary star, trinary variable star in the constellation Taurus (constellation), Taurus, the prototype of the T Tauri stars. It was discovered in October 1852 by John Russell Hind. T Tauri appears from Earth amongst the Hya ...

star, located in constellation Orion at 1200 light years from Earth with one candidate planet called CVSO 30 c. The candidate planet is a

gas giant A gas giant is a giant planet composed mainly of hydrogen and helium. Jupiter and Saturn are the gas giants of the Solar System. The term "gas giant" was originally synonymous with "giant planet". However, in the 1990s, it became known that Uranu ...

. The star is named after the CIDA Variability Survey of Orion (CVSO) and the

Palomar Transient Factory The Palomar Transient Factory (PTF, obs. code: I41), was an astronomical survey using a wide-field survey camera designed to search for optical transient and variable sources such as variable stars, supernovae, asteroids and comets. The projec ...

(PTF) and is within the 25 Ori group.

Planetary system

CVSO 30 may have one planet called CVSO 30 c. CVSO 30 c is calculated to have a period of 27,000 years and a semimajor axis of 660 AU. Direct imaging of the suspected CVSO 30 c, with a calculated mass equal to 4.7 Jupiter's, has been achieved through photometric and spectroscopic high contrast observations carried out with the

Very Large Telescope The Very Large Telescope (VLT) is an astronomical facility operated since 1998 by the European Southern Observatory, located on Cerro Paranal in the Atacama Desert of northern Chile. It consists of four individual telescopes, each equipped with ...

located in Chile, the

Keck Observatory The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have aperture primary mirrors, and, when c ...

in Hawaii and the

Calar Alto Observatory The Calar Alto Observatory (Centro Astronómico Hispano en Andalucía or "Spanish Astronomical Centre in Andalusia") is an astronomical observatory located in Almería province in Spain on Calar Alto, a mountain in the Sierra de Los Filabre ...

in Spain. However, the colors of the object suggest that it may actually be a background star, such as a K-type giant or a M-type

subdwarf A subdwarf, sometimes denoted by "sd", is a star with luminosity class VI under the Yerkes spectral classification system. They are defined as stars with luminosity 1.5 to 2 magnitudes lower than that of main-sequence stars of the same ...

By 2020, the phase of "dips" caused by suspected planet CVSO 30 b had drifted nearly 180 degrees from the expected value, thus ruling out the existence of the planet. Instead, a rare type of stellar starspot activity with very large starspots is now suspected. Also, CVSO 30 is suspected to be a stellar binary, with the previously reported planetary orbital period equal to the rotation period of the companion star. Further investigation of "dips" by 2022 led to hypothesis of a large gas cloud close to synchronous orbit, dust would likely sublimate.

Planetary system

References

Further reading