Table of Contents
- 1 What is the most abundant molecule in molecular clouds?
- 2 What happens to the rotation of a molecular cloud as a collapses to form a star?
- 3 What is the greatest mass a newborn star can have?
- 4 What is most likely the cause of the spiral pattern in galaxies like the Milky Way?
- 5 What kind of light can you see behind a molecular cloud?
- 6 What happens when a cloud reaches a critical density?
What is the most abundant molecule in molecular clouds?
A molecular cloud is an interstellar cloud of gas and dust in which molecules can form, the most common of which is hydrogen (H2).
How long does the Protostellar stage last for a star like our sun?
The more massive the star, the faster everything happens. Collapse into a star like our Sun takes about 50 million years. The collapse of a very high mass protostar might take only a million years. Smaller stars can take more than a hundred million years to form.
Why do stars along the edge of a molecular cloud appear redder in color?
Answer: Short wavelength (blue) light passing through a cloud is blocked more than longer (redder) wavelengths by the dust grains. Thus starlight passing through a cloud appears redder than in the absence of a cloud.
What happens to the rotation of a molecular cloud as a collapses to form a star?
What happens to the rotation of a molecular cloud as it collapses to form a star? The rotation rate increases and results in a disk of material around a protostar.
What are the two most common molecules in such a cloud?
CO and H2 are the most common molecules in interstellar gas clouds. The deep cold also causes the gas to clump to high densities. When the density reaches a certain point, stars form. Since the regions are dense, they are opaque to visible light and are known as dark nebula.
What is star life cycle?
Massive stars transform into supernovae, neutron stars and black holes while average stars like the sun, end life as a white dwarf surrounded by a disappearing planetary nebula. All stars, irrespective of their size, follow the same 7 stage cycle, they start as a gas cloud and end as a star remnant.
What is the greatest mass a newborn star can have?
A newborn star can have the greatest mass of 150 times the solar mass.
At what point is a star born?
Terms in this set (3) At what point is a star born? When the core of a protostar has reached about 10 million K, pressure within is so great that nuclear fusion of hydrogen begins, and a star is born.
Why is it so hard to see planets around other stars and so easy to see them around our own?
Why is it so hard to see planets around other stars and so easy to see them around our own? They are very far from earth and reflect a faint light making them hard to observe. Two protostars, one 10 times the mass of the Sun and one half the mass of the Sun are born at the same time in a molecular cloud.
What is most likely the cause of the spiral pattern in galaxies like the Milky Way?
Astronomers believe that a galaxy’s spiral structure originates as a density wave emanating from the galactic center. The idea is that the entire disk of a galaxy is filled with material. The spiral arms of a galaxy mark where in the galaxy the density wave recently passed, causing new stars to form and burn brightly.
What makes a cloud to spin faster?
Angular Momentum 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: L ~ mrv. And remember that angular momentum is conserved. So if a rotating cloud collapses (r gets smaller) than it must spin faster (v gets bigger).
Where does a protostar’s energy come from?
The energy generated from ordinary stars comes from the nuclear fusion occurring at their centers. Protostars also generate energy, but it comes from the radiation liberated at the shocks on its surface and on the surface of its surrounding disk.
What kind of light can you see behind a molecular cloud?
If you wanted to observe stars behind a molecular cloud, in what wavelength of light would you most likely observe? A. visible B. gamma-ray C. X-ray D. infrared E. ultraviolet D. infrared The typical size of an interstellar dust grain is The typical size of an interstellar dust grain is A. 1 centimeter. B. 1 micrometer. C. 1 millimeter.
Which is key observational evidence that stars are born in clouds of gas and dust?
Which of the following represents key observational evidence that stars are born in clouds of gas and dust? A. Younger star clusters have hotter and bluer stars than older star clusters. B. Young star clusters are always associated with clouds of gas and dust.
How are star forming clouds the same as the whole galaxy?
B. Star-forming clouds have the same overall chemical composition as the galaxy as a whole. C. Most of the hydrogen in star-forming clouds is in the form of hydrogen molecules (H2). D. The darkness of these clouds (in visible light) is due primarily to light absorption by tiny grains of interstellar dust.
What happens when a cloud reaches a critical density?
Once the cloud reaches a critical density, the pressure becomes degenerate and independent of temperature. B. The pressure is transferred from the center of the cloud to its outer edges where it can dissipate. C. As the cloud becomes denser, gravity becomes stronger and overcomes the pressure buildup.