HD 10647
Encyclopedia
HD 10647, also known as q1 Eridani by the extended Bayer system
, is a yellow-white dwarf
star
approximately 57 light-year
s away in the constellation
of Eridanus
(the River
). It is a relatively nearby 6th (almost 5th) magnitude
star. The star should be visible to the unaided eye under very dark skies, but with binoculars
it is an easy target. It is slightly hotter and more luminous than the Sun
. It is also younger being 1,750 million years old. As of 2003, a long-period extrasolar planet
has been confirmed to orbit around the star.
's team announced the discovery of a new planet, HD 10647 b
, in Paris at the XIX IAP Colloquium Extrasolar Planets: Today & Tormorrow. The Anglo-Australian Planet Search
team could not detect the planet, but that can be due to the poor coverage of observations. The star is also chromospherically
active, making radial velocity
observations more difficult.
The IRAS
infrared
space telescope
detected an excess of infrared
radiation from the star, indicating a possible circumstellar disk. Using this data and later observations with the Spitzer Space Telescope
, Infrared Space Observatory
and the Atacama Pathfinder Experiment
implies that the disk is located at 25 Astronomical unit
s and has a ring like structure. Because of the age of the star, the disk probably is somewhat similar to our Solar System's
Kuiper belt
instead of a protoplanetary disk
seen around young stars like Vega
.
Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name...
, is a yellow-white dwarf
Yellow-white dwarf
An F-type main-sequence star is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K., Tables VII and VIII. This temperature range gives the F-type stars a...
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...
approximately 57 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s away in the constellation
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 Eridanus
Eridanus (constellation)
Eridanus is a constellation. It is represented as a river; its name is the Ancient Greek name for the Po River. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is the sixth largest of the modern...
(the River
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
). It is a relatively nearby 6th (almost 5th) magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
star. The star should be visible to the unaided eye under very dark skies, but with binoculars
Binoculars
Binoculars, field glasses or binocular telescopes are a pair of identical or mirror-symmetrical telescopes mounted side-by-side and aligned to point accurately in the same direction, allowing the viewer to use both eyes when viewing distant objects...
it is an easy target. It is slightly hotter and more luminous than 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...
. It is also younger being 1,750 million years old. As of 2003, a long-period extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
has been confirmed to orbit around the star.
Planetary system
In 2003, Michel MayorMichel Mayor
Dr. Michel G. E. Mayor is a Swiss astrophysicist and professor emeritus at the University of Geneva's Department of Astronomy. He formally retired in 2007, but remains active as a researcher at the Observatory of Geneva...
's team announced the discovery of a new planet, HD 10647 b
HD 10647 b
HD 10647 b, also catalogued as q1 Eridani b, is an extrasolar planet approximately 57 light-years away in the constellation of Eridanus . The planet is a mid-Jovian that orbits 103% farther from the star than Earth to the Sun. It takes about 33 months to orbit with semi-amplitude of 17.9 m/s.-...
, in Paris at the XIX IAP Colloquium Extrasolar Planets: Today & Tormorrow. The Anglo-Australian Planet Search
Anglo-Australian Planet Search
The Anglo-Australian Planet Search or AAPS is a long-term astronomical survey started in 1998 and continuing to the present. It is being carried out on the 3.9m Anglo-Australian Telescope, AAT, of the Anglo-Australian Observatory in Australia. The purpose of this survey is to catalog planets around...
team could not detect the planet, but that can be due to the poor coverage of observations. The star is also chromospherically
Chromosphere
The chromosphere is a thin layer of the Sun's atmosphere just above the photosphere, roughly 2,000 kilometers deep....
active, making radial velocity
Radial velocity
Radial velocity is the velocity of an object in the direction of the line of sight . In astronomy, radial velocity most commonly refers to the spectroscopic radial velocity...
observations more difficult.
The IRAS
IRAS
The Infrared Astronomical Satellite was the first-ever space-based observatory to perform a survey of the entire sky at infrared wavelengths....
infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
space telescope
Telescope
A telescope is an instrument that aids in the observation of remote objects by collecting electromagnetic radiation . The first known practical telescopes were invented in the Netherlands at the beginning of the 1600s , using glass lenses...
detected an excess of infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
radiation from the star, indicating a possible circumstellar disk. Using this data and later observations with the Spitzer Space Telescope
Spitzer Space Telescope
The Spitzer Space Telescope , formerly the Space Infrared Telescope Facility is an infrared space observatory launched in 2003...
, Infrared Space Observatory
Infrared Space Observatory
The Infrared Space Observatory was a space telescope for infrared light designed and operated by the European Space Agency , in cooperation with ISAS and NASA...
and the Atacama Pathfinder Experiment
Atacama Pathfinder Experiment
The Atacama Pathfinder Experiment is a radio telescope located at 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert, in northern Chile, 50 kilometers to the east of San Pedro de Atacama. The main dish has a diameter of 12 meters and consists of 264...
implies that the disk is located at 25 Astronomical unit
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
s and has a ring like structure. Because of the age of the star, the disk probably is somewhat similar to our Solar System's
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
Kuiper belt
Kuiper belt
The Kuiper belt , sometimes called the Edgeworth–Kuiper belt, is a region of the Solar System beyond the planets extending from the orbit of Neptune to approximately 50 AU from the Sun. It is similar to the asteroid belt, although it is far larger—20 times as wide and 20 to 200 times as massive...
instead of a protoplanetary disk
Protoplanetary disk
A protoplanetary disk is a rotating circumstellar disk of dense gas surrounding a young newly formed star, a T Tauri star, or Herbig Ae/Be star...
seen around young stars like Vega
Vega
Vega is the brightest star in the constellation Lyra, the fifth brightest star in the night sky and the second brightest star in the northern celestial hemisphere, after Arcturus...
.