Messier 78 or M78, also known as NGC 2068, is a
reflection nebula in the
constellation Orion. It was discovered by
Pierre Méchain
Pierre François André Méchain (; 16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep-sky objects and comets.
Life
Pierre Méchain was bo ...
in 1780 and included by
Charles Messier in his catalog of
comet
A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or Coma (cometary), coma, and sometimes also a Comet ta ...
-like objects that same year.
[
M78 is the brightest diffuse reflection nebula of a group of nebulae that includes NGC 2064, NGC 2067 and NGC 2071. This group belongs to the Orion B molecular cloud complex and is about distant from Earth.][ M78 is easily found in small ]telescope
A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to obse ...
s as a hazy patch and involves two stars of 10th and 11th magnitude. These two B-type stars, and , are responsible for making the cloud of dust in M78 visible by reflecting their light.[
The M78 cloud contains a cluster of stars that is visible in the ]infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from aroun ...
.[ Due to gravity, the molecular gas in the nebula has fragmented into a hierarchy of clumps,][ whose cores have masses ranging from to .][ About 45 ]variable star
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as e ...
s of the ''T Tauri'' type,[ young stars still in the process of formation, are members as well. Similarly, 17 Herbig–Haro objects are known in M78.][
]
Gallery
VISTA views Messier 78.jpg, VISTA image of Messier 78.
Making a Spectacle of Star Formation in Orion.jpg, Spitzer image of Messier 78.
See also
* List of Messier objects
References
External links
*
SEDS: Starforming Nebula M78
*
NightSkyInfo.com – M78
* Astronomy Picture of the Day
Astronomy Picture of the Day (APOD) is a website provided by NASA and Michigan Technological University (MTU). According to the website, "Each day a different image or photograph of our universe is featured, along with a brief explanation written ...
*
M78 Wide Field
2009 November 26
*
2010 March 2
*
{{Sky, 05, 46.7, 00, +, 00, 03, 00, 1600
Messier 078
Messier 078
Orion–Cygnus Arm
Messier 078
078 78 may refer to:
* 78 (number)
* one of the years 78 BC, AD 78, 1978, 2078
In contemporary history, the third millennium of the anno Domini or Common Era in the Gregorian calendar is the current millennium spanning the years 2001 to 3000 ( 21 ...
Messier 078
Astronomical objects discovered in 1780
Discoveries by Pierre Méchain