Messier 78 or M78, also known as NGC 2068, is a reflection nebula in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

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 warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

-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 (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using len ...

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 that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

. 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 systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

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. On May 23, 2024, the

European Space Agency The European Space Agency (ESA) is a 23-member International organization, international organization devoted to space exploration. With its headquarters in Paris and a staff of around 2,547 people globally as of 2023, ESA was founded in 1975 ...

released an initial set of images from their Euclid mission. This included an unprecedented image of the region including M78. It showed hundreds of thousands of new objects including sub-stellar sized ones for the first time.

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. Euclid’s new image of star-forming region Messier 78 ESA497237.jpg,

Euclid Euclid (; ; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of geometry that largely domina ...

image of star-forming region Messier 78

Gallery

See also

References

External links