HD 181720
Encyclopedia
HD 181720 is an 8th 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 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 Hertzsprungā€“Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell...

 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...

 located approximately 190 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....

 Sagittarius
Sagittarius (constellation)
Sagittarius is a constellation of the zodiac, the one containing the galactic center. Its name is Latin for the archer, and its symbol is , a stylized arrow. Sagittarius is commonly represented as a centaur drawing a bow...

. This star is larger, hotter, brighter, and less massive than our Sun. Also its metal
Metallicity
In astronomy and physical cosmology, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium...

 content is three-tenths as much as the Sun. In 2009, a gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...

 planet was found in orbit around the star.
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