What is molecular cloud in astronomy?

A molecular cloud is an interstellar cloud of gas and dust in which molecules can form, the most common of which is hydrogen (H2).

Are molecular clouds the same as nebula?

molecular cloud, also called dark nebula, interstellar clump or cloud that is opaque because of its internal dust grains. The form of such dark clouds is very irregular: they have no clearly defined outer boundaries and sometimes take on convoluted serpentine shapes because of turbulence.

Why are molecular clouds so important to astronomers?

Star formation takes place exclusively within molecular clouds and observations have shown that they are located primarily in the disk of spiral galaxies and the active regions of irregular galaxies. Since molecular clouds are cold and dark, we cannot observe them directly in visible light.

How do astronomers detect molecular clouds?

Using radio observations to identify the chemical makeup of dust clouds. The National Radio Astronomy Observatory’s Green Bank Telescope (GBT) is particularly suited to studying molecular clouds that are opaque to visible light.

How molecular cloud is formed?

Molecular clouds are expected to be formed in limited regions where the mean magnetic field is parallel to the direction of shock wave propagation or in regions where an excessive number of shock wave sweepings are experienced. Therefore, molecular clouds can only be found in limited regions in shells.

Is the Orion Nebula A molecular cloud?

Orion B. Orion B is also a giant molecular cloud that is around 1370 light years (420 parsec) away from Earth. It has a size of about 1.5 kpc² and a mass around 105 times that of the Sun. Orion B is home to several star forming regions, including the Flame Nebula and the Horsehead Nebula.

What are the 2 reasons molecular clouds are the perfect place for star formation?

Molecular clouds are favorable locations for star formation for two reasons: low temperature and high density. Their low temperature keeps their pressures about the same as other interstellar clouds, despite the higher density.

Where do molecular clouds come from?

Is the Orion nebula A molecular cloud?

Why is the Orion Molecular Cloud important?

Orion A. The giant molecular cloud Orion A is the most active star-forming region in the local neighbourhood of the Sun. In the last few million years about 3000 young stellar objects were formed in this region, including about 190 protostars and about 2600 pre-main sequence stars.

Why is it important for a molecular cloud to be cold for star formation?

In the colder, denser areas, and under the right conditions, stars are formed. Theoretically, in molecular clouds at temperatures of 10 Kelvin, all molecules except hydrogen and helium should be locked into ice on the surface of dust, not freely floating around.