A nebula is a giant cloud of dust and gas in space. Some nebulae (more than one nebula) come from the gas and dust thrown out by the explosion of a dying star, such as a supernova. Other nebulae are regions where new stars are beginning to form. ... Other nebulae are regions where new stars are beginning to form.

nebula is a gaint ☁ cloud of dust and gas in space

a nebula is a formation in space which is constituted mostly of helium.

Anebula(Latinfor 'cloud' or 'fog';[2]pl.nebulae,nebulæ, ornebulas) is aninterstellar cloudofdust,hydrogen,heliumand otherionized gases. Originally, the term was used to describe any diffuseastronomical object, includinggalaxiesbeyond theMilky Way. TheAndromeda Galaxy, for instance, was once referred to as theAndromeda Nebula(andspiral galaxiesin general as "spiral nebulae") before the true nature of galaxies was confirmed in the early 20th century byVesto Slipher,Edwin Hubbleand others.

Most nebulae are of vast size; some are hundreds oflight-yearsin diameter. A nebula that is barely visible to the human eye from Earth would appear larger, but no brighter, from close by.[3]TheOrion Nebula, the brightest nebula in the sky and occupying an area twice the diameter of the full Moon, can be viewed with the naked eye but was missed by early astronomers.[4]Although denser than the space surrounding them, most nebulae are far less dense than anyvacuumcreated on Earth – a nebular cloud the size of theEarthwould have a total mass of only a fewkilograms. Many nebulae are visible due to fluorescence caused by embedded hot stars, while others are so diffuse they can only be detected with long exposures and special filters. Some nebulae are variably illuminated byT Taurivariable stars. Nebulae are often star-forming regions, such as in the "Pillars of Creation" in theEagle Nebula. In these regions the formations of gas, dust, and other materials "clump" together to form denser regions, which attract further matter, and eventually will become dense enough to formstars. The remaining material is then believed to formplanetsand otherplanetary system