Table of Contents
What is protogalactic clouds?
In physical cosmology, a protogalaxy, which could also be called a “primeval galaxy”, is a cloud of gas which is forming into a galaxy.
Why do galaxies have angular momentum?
“Till recent years, in the paradigm of galaxy formation and evolution, elliptical galaxies were thought to have formed by the merging of stellar disks in the distant Universe. Along this line, their angular momentum was thought to be the result of dissipative processes during such merging events” say the researchers.
What is the meaning of protogalaxy?
Definition of protogalaxy : a cloud of gas believed to be the precursor to a galaxy.
How did the first proto galaxies and stars form?
Astronomers believe that the first proto-galaxies formed about one billion years after the Big Bang. Around this time, dark matter began to gather in small clumps attracted by its own gravity. These clumps joined together to create larger clumps, which in turn combined to make even larger clumps.
What is a Protogalactic cloud quizlet?
Protogalactic clouds. The denser areas of gas in space originally expanded with the universe but then stopped and contracted into protogalactic clouds.
What is the difference between how elliptical galaxies form from a Protogalactic cloud and how a spiral galaxy forms?
Slowly rotating or high-density protogalactic clouds may form elliptical rather than spiral galaxies. Ellipticals may also form through the collision and merger of 2 spiral galaxies.
What is the angular momentum of the universe?
Answer. The answer is no: or at least, the total angular momentum of the universe is zero. The equations that describe our universe are predicated on the assumption that the universe is isotropic. That means there is no preferred direction in space.
Where does angular momentum come from?
Angular momentum is defined as the product of an object’s moment of inertia (the resistance of angular acceleration) with it’s angular velocity (how fast it is spinning).
What do we mean by a Protogalactic cloud quizlet?
What do we mean by a protogalactic cloud? A cloud of hydrogen and helium that contracts to become a galaxy.
Why do we think that clouds of gas and dust form stars?
Stars are born within the clouds of dust and scattered throughout most galaxies. A familiar example of such as a dust cloud is the Orion Nebula. Turbulence deep within these clouds gives rise to knots with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction.
What causes clouds of dust and gas to form a protostar?
When the force of gravity pulling in on the cloud is greater than the strength of internal pressure pushing out, the cloud collapses into a protostar.
What Protogalactic cloud would be most likely to form an elliptical galaxy?
3) A protogalactic cloud with very little angular momentum is more likely to form an elliptical galaxy than a spiral galaxy.
How do elliptical galaxies form from Protogalactic cloud?
As protogalactic clouds that had very little angular momentum evolved into galaxies, they would not have formed disks. As a result, they would have become elliptical galaxies.
What conditions in a Protogalactic cloud system might lead to an elliptical rather than a spiral galaxy?
Describe two ways in which conditions in a protogalactic cloud might lead to the birth of an elliptical rather than a spiral galaxy. If cloud had little or no angular momentum, then its gas might not collapse into a disk at all, leading to formation of elliptical galaxy.
Why does angular momentum exist?
In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important quantity in physics because it is a conserved quantity—the total angular momentum of a closed system remains constant….
| Angular momentum | |
|---|---|
| Dimension | M L2T−1 |
How do you increase angular momentum?
If you increase the force by a factor of 3 and push for the same amount of time, the angular momentum increases by a factor of three. The moment of inertia of the door does not change, so its angular velocity must increase by a factor of 3.
How did star formation likely proceed in the Protogalactic cloud that formed the Milky Way quizlet?
How did star formation likely proceed in the protogalactic cloud that formed the Milky Way? The stars that formed first could orbit the center of the galaxy in any direction at any inclination.
What are Magellanic Clouds quizlet?
The Large and Small Magellanic Clouds are two small galaxies that orbit the Milky Way at distances of some 150,000 and 200,000 light-years, respectively and they are both visible to the naked eye in the Southern Hemisphere.
How does the contraction of a gas cloud increase its temperature?
How does the contraction of a gas cloud increase its temperature? Collisions convert the inward velocities of the atoms into random motions, thus the temperature of the gas goes up. Conversion of potential gravitational energy to thermal energy.
Where do galaxies acquire most of their angular momentum?
This stage is also where galaxies acquire most of their angular momentum. A protogalaxy acquires this due to gravitational influence from neighbouring dense clumps in the early universe, and the further the gas is away from the centre, the more spin it gets. The luminosity of protogalaxies comes from two sources.
What is protogalaxy in astronomy?
Protogalaxy. It is believed that the rate of star formation during this period of galactic evolution will determine whether a galaxy is a spiral or elliptical galaxy; a slower star formation tends to produce a spiral galaxy. The smaller clumps of gas in a protogalaxy form into stars .
What do the smaller clumps of gas in a protogalaxy form?
The smaller clumps of gas in a protogalaxy form into stars . The term “protogalaxy” itself is generally accepted to mean “Progenitors of the present day (normal) galaxies, in the early stages of formation.” However, the “early stages of formation” is not a clearly defined phrase.
What causes the luminosity of protogalaxies?
The luminosity of protogalaxies comes from two sources. First and foremost is the radiation from nuclear fusion of Hydrogen into helium in early stars. This early burst of star formation is thought to have made a protogalaxy’s luminosity comparable to a present-day starburst galaxy or a quasar.