Becklin-Neugebauer Object
Encyclopedia
The Becklin-Neugebauer Object (BN) is an object visible only in the infrared
in the Orion Molecular Cloud
. It was discovered in 1967 by Eric Becklin
and Gerry Neugebauer during their near-infrared
survey of the Orion Nebula
.
The BN Object is thought to be an intermediate-mass protostar
. It was the first star detected using infrared methods and is deeply embedded within the Orion star-forming
nebula
, where it is invisible at optical wavelengths because the light is completely scattered or absorbed due to the high density of dusty material.
The BN Object is the brightest object in the sky (apart from the Sun
) at wavelengths of less than 10 micrometre
s. It is about the size of the Solar System
and has a surface temperature of only about 700 K, but deep inside, hidden from view, is a luminous star with a mass of some 15 solar mass
es and a surface temperature of some 26,000 K. Its birthing process involved the hot, bright stars of the Trapezium
whose radiation exerts pressure on the nebular material around them. In the direction toward the Sun, this pressure has already dispersed the remaining dust and gas from which the Trapezium stars formed. In the direction away from us, however, the radiation pressure continues to compress dust and gas, triggering the collapse of new stars.
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...
in the Orion Molecular Cloud
Orion Molecular Cloud Complex
The Orion Molecular Cloud Complex refers to a large group of bright nebula, dark clouds, and young stars located in the constellation of Orion. The cloud itself is between 1,500 and 1,600 light-years away and is hundreds of light-years across...
. It was discovered in 1967 by Eric Becklin
Eric Becklin
Eric E. Becklin is an American astrophysicist, best known for his pioneering study of infra-red sources at the center of our galaxy....
and Gerry Neugebauer during their near-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...
survey of the Orion Nebula
Orion Nebula
The Orion Nebula is a diffuse nebula situated south of Orion's Belt. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light...
.
The BN Object is thought to be an intermediate-mass protostar
Protostar
A protostar is a large mass that forms by contraction out of the gas of a giant molecular cloud in the interstellar medium. The protostellar phase is an early stage in the process of star formation. For a one solar-mass star it lasts about 100,000 years...
. It was the first star detected using infrared methods and is deeply embedded within the Orion star-forming
Star formation
Star formation is the process by which dense parts of molecular clouds collapse into a ball of plasma to form a star. As a branch of astronomy star formation includes the study of the interstellar medium and giant molecular clouds as precursors to the star formation process and the study of young...
nebula
Nebula
A nebula is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases...
, where it is invisible at optical wavelengths because the light is completely scattered or absorbed due to the high density of dusty material.
The BN Object is the brightest object in the sky (apart 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...
) at wavelengths of less than 10 micrometre
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
s. It is about the size of the 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...
and has a surface temperature of only about 700 K, but deep inside, hidden from view, is a luminous star with a mass of some 15 solar mass
Solar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...
es and a surface temperature of some 26,000 K. Its birthing process involved the hot, bright stars of the Trapezium
Trapezium (astronomy)
The Trapezium, or Orion Trapezium Cluster is a tight open cluster of stars in the heart of the Orion Nebula, in the constellation of Orion. It was discovered by Galileo Galilei. On February 4, 1617 he sketched three of the stars , but missed the surrounding nebulosity...
whose radiation exerts pressure on the nebular material around them. In the direction toward the Sun, this pressure has already dispersed the remaining dust and gas from which the Trapezium stars formed. In the direction away from us, however, the radiation pressure continues to compress dust and gas, triggering the collapse of new stars.
External links
- Becklin-Neugebauer object (Encyclopædia Britannica)
- Periodic Photometric Variability in the Becklin-Neugebauer Object (Astrophysical Journal)
- The Secret Inner Life of the Orion Nebula (Astronomical Society of Australia)
- The Becklin-Neugebauer Object: Circumstellar Disk Cradles Young Massive Star (Adaptiveoptics.org)
- A circumstellar disk associated with a massive protostellar object (Nature)
- The Becklin-Neugebauer Object as a Runaway B Star, Ejected 4000 Years Ago from the θ1 Orionis C System (Astrophysical Journal)