European Southern Observatory infrared image of 2M1207 (bluish) and companion planet 2M1207b (reddish), taken in 2004. The cosmic distance ladder (also known as the Extragalactic Distance Scale) is the succession of methods by which astronomers determine the Distances to celestial A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by History The first direct measurements of an object at interstellar distances were undertaken by German Astronomer Friedrich Wilhelm Bessel in 1838 In Astronomy, stellar classification is a classification of Stars based initially on photospheric temperature and its associated Spectral characteristics A star catalogue, or star catalog, is an Astronomical catalogue that lists Stars In Astronomy, many stars are referred to simply by catalogue 2M1207b is a Planetary mass object orbiting the Brown dwarf 2M1207, in the constellation Centaurus, approximately 170 Light-years

2M1207, 2M1207A or 2MASSW J1207334−393254 is a brown dwarf located in the constellation Centaurus; a companion object, 2M1207b, is believed to be one of the first extrasolar planets to be directly imaged, and is the first exoplanet to be discovered in orbit of a brown dwarf. Brown dwarfs are sub- stellar objects with a mass below that necessary to maintain Hydrogen -burning Nuclear fusion reactions in their cores as do stars In common usage a constellation is a group of celestial bodies that are connected together in some arrangement typically stars to form a visible figure or picture Centaurus ( Centaur) is a bright constellation of the southern hemisphere. 2M1207b is a Planetary mass object orbiting the Brown dwarf 2M1207, in the constellation Centaurus, approximately 170 Light-years An extrasolar planet, or exoplanet, is a Planet beyond the Solar System, orbiting around other Stars As of September 2008 312

2M1207 was discovered during the course of the 2MASS infrared sky survey: hence the "2M" in its name, followed by its celestial coordinates. Observations for the Two Micron All-Sky Survey ( 2MASS) began in 1997 and were completed in 2001 at two Telescopes located one each in the northern and Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of It is roughly 53 parsecs away; with a fairly early (for a brown dwarf) spectral type of M8, it is very young, and a likely member of the TW Hydrae association. History The first direct measurements of an object at interstellar distances were undertaken by German Astronomer Friedrich Wilhelm Bessel in 1838 In Astronomy, stellar classification is a classification of Stars based initially on photospheric temperature and its associated Spectral characteristics TW Hydrae is an Orange dwarf Star approximately 176 Light-years away in the Constellation of Hydra (the Sea Serpent Its estimated mass is around 21 Jupiter masses and 1. 8 times the radius of Jupiter. The planet is estimated to be 5 Jupiter Masses and is still glowing red hot and will shrink to Jupiter's current size as it cools over the next few billion years.

In December 2005, American astronomer Eric Mamajek reported a more accurate distance (53+-6 parsecs) to 2M1207 using the moving cluster method^[1]. The new distance (revised downwards from 70 parsecs) results in a fainter luminosity for 2M1207A, and its mass was revised downwards from an original value of 25 Jupiter masses. Luminosity has different meanings in several different fields of science Recent trigonometric parallax results have confirmed the moving cluster distance, leading to a distance estimate of 53+-1 parsec or 172+-3 light years. History The first direct measurements of an object at interstellar distances were undertaken by German Astronomer Friedrich Wilhelm Bessel in 1838 A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by

A report in the March '07 issue of the Astrophysical Journal reports that this brown dwarf is spouting jets of material from its poles. ^[2]

2M1207's streaming jets were discovered using the European Southern Observatory's Very Large Telescope (VLT). The jets extend about 620 million miles (1 billion km) into space and are speeding away from the brown dwarf at a few kilometers per second.

"Preliminary results suggest that a brown-dwarf jet is just scaled down from what we see in a low mass star," said study leader Emma Whelan of the Dublin Institute for Advanced Physics in Ireland.

References

• Space.com - Astronomers Confident: Planet Beyond Solar System Has Been Photographed
• Space.com article on the discovery
• Extrasolar Planets Encyclopedia page on 2M1207 b
• "A Giant Planet Candidate Near a Young Brown Dwarf" (PDF) from the European Southern Observatory.
• "A Moving Cluster Distance to the Exoplanet 2M1207b in the TW Hydrae Association"
• "The Distance to the 2M1207 System"