HR 753
Encyclopedia
HR 753 is a triple star system in the constellation
of Cetus
. It is located relatively near the Sun
at an estimated distance of less than 24 light years, but even the brightest component is too faint to see directly with the unaided eye. No planets have yet been detected around any of the star
s in this system.
The companion star B has a common proper motion
with A, and the two have an estimated separation of 1,200 AUs
. It is a BY Draconis variable
star that has been given the designation "BX Ceti".
The third companion C lies much closer to A, at a distance of approximately 24 AU. The pair A-C have an estimated orbital period of 61 years. Component C is a relatively minuscule star that lies at the low end of the mass range needed to achieve nuclear fusion
.
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
of Cetus
Cetus
Cetus is a constellation. Its name refers to Cetus, a sea monster in Greek mythology, although it is often called 'the whale' today. Cetus is located in the region of the sky that contains other water-related constellations such as Aquarius, Pisces, and Eridanus.-Ecliptic:Although Cetus is not...
. It is located relatively near the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
at an estimated distance of less than 24 light years, but even the brightest component is too faint to see directly with the unaided eye. No planets have yet been detected around any of the star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
s in this system.
The companion star B has a common proper motion
Proper motion
The proper motion of a star is its angular change in position over time as seen from the center of mass of the solar system. It is measured in seconds of arc per year, arcsec/yr, where 3600 arcseconds equal one degree. This contrasts with radial velocity, which is the time rate of change in...
with A, and the two have an estimated separation of 1,200 AUs
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
. It is a BY Draconis variable
BY Draconis variable
BY Draconis variables are main sequence variable stars of late spectral types, usually K or M. The name comes from the archetype for this category of variable star system, BY Draconis. They exhibit variations in their luminosity due to rotation of the star coupled with star spots, and other...
star that has been given the designation "BX Ceti".
The third companion C lies much closer to A, at a distance of approximately 24 AU. The pair A-C have an estimated orbital period of 61 years. Component C is a relatively minuscule star that lies at the low end of the mass range needed to achieve nuclear fusion
Nuclear fusion
Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...
.
External links
- Gliese 105 / HR 753 ABC SolStation entry.
- Hubble Spies a Really Cool Star
- Gliese 105