Dust and gas
primarily in the form of hydrogen molecules are the main constituents of the coldest, densest clouds in the interstellar medium.
What is the most common element in giant molecular cloud?
A molecular cloud is an interstellar cloud of gas and dust in which molecules can form, the most common of which is
hydrogen (H2)
.
Which of the following might be found in a giant molecular cloud?
Giant molecular clouds are vast cosmic objects, composed primarily of
hydrogen molecules and helium atoms
, where new stars and planets are born. These clouds can contain more mass than a million suns, and stretch across hundreds of light years.
What are giant molecular clouds quizlet?
A large cloud of
interstellar gas and dust
in which temperatures are low enough and densities high enough for atoms to form into molecules.
What are giant molecular clouds and where are they found what role do they play in star formation?
Star Formation. Stars
form inside relatively dense concentrations of interstellar gas and dust
known as molecular clouds. These regions are extremely cold (temperature about 10 to 20K, just above absolute zero). At these temperatures, gases become molecular meaning that atoms bind together.
Why do molecular clouds spin?
All clouds rotate, at least a little,
due to gravitational shearing in the galaxy’s disk
. And if a cloud rotates, it has angular momentum: And remember that angular momentum is conserved. So if a rotating cloud collapses (r gets smaller) than it must spin faster (v gets bigger).
Why do molecular clouds exist?
Molecular clouds are so important because
they are the raw material of stars and planets
. A dark nebula (or dark cloud) is a very dense part of a bigger molecular cloud; the light extinction is caused by the high density and the presence of interstellar dust in these clouds.
Where are most of the giant molecular clouds in our galaxy?
The most massive collection of molecular clouds in the galaxy forms an asymmetrical ring about the galactic center at a radius of 120 parsecs; the largest component of this ring is
the Sagittarius B2 complex
.
What are interstellar clouds called?
Molecular cloud, also called
dark nebula
, interstellar clump or cloud that is opaque because of its internal dust grains.
What gases are in a nebula?
The roots of the word come from Latin nebula, which means a “mist, vapor, fog, smoke, exhalation.” Nebulae are made up of
dust, basic elements such as hydrogen and other ionized gases
. They either form through clouds of cold interstellar gas and dust or through the aftermath of a supernova.
What are giant molecular clouds and where are they found?
Giant molecular clouds are
vast cosmic objects
, composed primarily of hydrogen molecules and helium atoms, where new stars and planets are born. These clouds can contain more mass than a million suns, and stretch across hundreds of light years.
What happens to a giant molecular cloud as it forms into a protostar quizlet?
Gravity is stronger in a high-mass gas cloud, so it is easier for gravity to overcome pressure. Molecular clouds are lumpy and turbulent; clumps move at different speeds; these smaller, dense clumps can shrink on their own. …
The clump of gas then
becomes a protostar; the first stage of star formation.
Why do H II regions glow quizlet?
The H II region glows
red because of a specific emission line in hydrogen
. blue light, preferentially scattered by tiny dust grains. thermal energy emitted as a continuous spectrum by very hot gas, much like that emitted by a hot body on Earth.
How are star formed?
Stars form from
an accumulation of gas and dust
, which collapses due to gravity and starts to form stars. The process of star formation takes around a million years from the time the initial gas cloud starts to collapse until the star is created and shines like the Sun.
What stars form the slowest?
What stars form the slowest?
infrared spectrum
.
How is energy of star produced?
Stars produce energy from nuclear reactions,
primarily the fusion of hydrogen to form helium
. These and other processes in stars have lead to the formation of all the other elements. On the basis of scientific evidence, the universe is estimated to be over ten billion years old.
