HD 70642
Encyclopedia
HD 70642 is a yellow dwarf
Yellow dwarf
A G-type main-sequence star , often called a yellow dwarf, is a main-sequence star of spectral type G and luminosity class V. Such a star has about 0.8 to 1.2 solar masses and surface temperature of between 5,300 and 6,000 K., Tables VII, VIII...

 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...

 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 Puppis
Puppis
Puppis is a constellation in the southern sky. Its name is the Latin word for the poop deck of a ship, and Puppis represents the deck of the ship and its deckhouses...

 located 93.8 light years away. This star has about the same mass and radius as 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...

, is slightly cooler and less luminous, and is richer in abundance of iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 relative to hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

.

Planetary system

A long period planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...

 companion to HD 70642 was announced in 2003. This planet orbits in a circular orbit (e=0.034) at 3.232 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

. The star is so like to Sol that its habitable zone is in the same place (~ 1 AU). The jovian ensures the stability of an Earth-mass planet at 1 AU. This system is one of the most similar in conditions to our solar system
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...

 than any other currently known planetary systems.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK