HD 173416 b
Encyclopedia
HD 173416 b is an extrasolar planet
located approximately 440 light years away in the constellation
of Lyra, orbiting the 6th magnitude
G-type giant star
HD 173416
. This is planet has at least 2.7 times the mass of Jupiter and was discovered on January 10, 2009 by Liu et al. HD 173416 b orbits at 1.16 AU
from the star. However despite the fact that the planet orbits 16% further from the star than Earth
does from the Sun
, it has orbital period of only 323.6 days, compared to 365.25 days for Earth. This inverse relationship is caused by the parent star having twice the mass of our Sun, which increases the strength of its gravitional field. This evidence implies that when this star was on the main sequence
, it was an A-type star.
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...
located approximately 440 light years 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 Lyra, orbiting the 6th 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...
G-type giant 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...
HD 173416
HD 173416
|- bgcolor="#FFFAFA"HD 173416 is an intermediate-mass giant star in the constellation Lyra. It is a 6th magnitude star, relatively bright for its distance of about 440 light years from Earth.-Planetary system:...
. This is planet has at least 2.7 times the mass of Jupiter and was discovered on January 10, 2009 by Liu et al. HD 173416 b orbits at 1.16 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
from the star. However despite the fact that the planet orbits 16% further from the star than Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
does from 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 has orbital period of only 323.6 days, compared to 365.25 days for Earth. This inverse relationship is caused by the parent star having twice the mass of our Sun, which increases the strength of its gravitional field. This evidence implies that when this star was on the main sequence
Main sequence
The main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell...
, it was an A-type star.