What is the net effect of the star-gas-star cycle?

Over time, what is the net effect of the star-gas-star cycle in the Milky Way? The total mass in the galaxy’s interstellar medium is gradually reduced, and the remaining gas is continually enriched in heavy elements.

Besides, What kinds of objects lie in the halo of our galaxy?

The Milky Way’s stellar halo contains globular clusters, RR Lyrae stars with low metal content, and subdwarfs. Stars in our stellar halo tend to be old (most are greater than 12 billion years old) and metal-poor, but there are also halo star clusters with observed metal content similar to disk stars.

Keeping this in mind, What determines a star’s life cycle? A star’s life cycle is determined by its mass. The larger its mass, the shorter its life cycle. A star’s mass is determined by the amount of matter that is available in its nebula, the giant cloud of gas and dust from which it was born. … As the gas spins faster, it heats up and becomes as a protostar.

How did we measure the mass of Sagittarius A * Sgr A *)?

From examining the Keplerian orbit of S2, they determined the mass of Sagittarius A* to be 4.1±0.6 million solar masses, confined in a volume with a radius no more than 17 light-hours (120 AU). … This black hole of 1,300 solar masses is within a cluster of seven stars.

What evidence supports the theory that there is a black hole at the center of our galaxy?

What evidence supports the theory that there is a black hole at the center of our galaxy? The motions of the gas and stars at the center indicate that it contains a million solar masses within a region only about 1 parsec across.

What is in the halo of the Milky Way?

A halo is a large region filled with hot gas that surrounds a galaxy, also known as a “circumgalactic medium.” The heated gaseous halo around the Milky Way was the incubator for the Milky Way’s formation some 13 billion years ago and could help solve a longstanding puzzle about where the missing matter of the universe …

What kind of star is most likely to be found in the halo?

Old stars with few heavy elements are referred to as population II stars and are found in the halo and in globular clusters. Population I stars contain more heavy elements than globular cluster and halo stars, are typically younger and found in the disk, and are especially concentrated in the spiral arms.

Which of these objects are not found in the galactic halo?

Which of these objects have not been found in the Galactic Halo? barred spiral galaxy. Which is the correct description for the Sun’s location in the Galaxy?

What two factors determine how long a star stays on the main sequence?

The rate at which they do this and the amount of fuel available depends upon the mass of the star. Mass is the key factor in determining the lifespan of a main sequence star, its size and its luminosity. Stars on the main sequence also appear to be unchanging for long periods of time.

Do all stars have the same life cycle?

All stars begin life in the same way. A cloud of dust and gas, also known as a nebula , becomes a protostar, which goes on to become a main sequence star. Following this, stars develop in different ways depending on their size.

How is the main sequence stage of a star’s life defined when does it start when does it end?

When the stars go out

Eventually, a main sequence star burns through the hydrogen in its core, reaching the end of its life cycle. At this point, it leaves the main sequence. Stars smaller than a quarter the mass of the sun collapse directly into white dwarfs.

How do you calculate the mass of a Sagittarius?

It has a period of about 15.56 years and a semi-major axis of about 1,000AU. Putting the figures into Kepler’s equation 10003=15.562M . This gives the value of M=4,130,000 solar masses. Current estimates for the mass of Sagittarius A* are 4,300,000 solar masses.

What is the mass of Sagittarius A *?

Sagittarius A

What is Sagittarius A * quizlet?

Sagittarius A. is a bright and very compact astronomical radio source at the center of the Milky Way Galaxy, It is believed to be the location of a supermassive black hole, which is now generally accepted to be at the centers of many spiral and elliptical galaxies. Shapley-Curtis debate.

What evidence supports the existence of black holes?

The best evidence of stellar-mass black holes comes from binary star systems in which (1) one star of the pair is not visible, (2) the flickering X-ray emission is characteristic of an accretion disk around a compact object, and (3) the orbit and characteristics of the visible star indicate that the mass of its …

What observational evidence supports the existence of black holes?

The first is observational. For small (stellar mass) black holes, the best evidence is through micro-quasars, also known as x-ray binaries. These objects emit strong x-rays from an Earth-sized region in space.

What is the best evidence for supermassive black holes existing in the centers of other galaxies?

What is the best evidence for supermassive black holes existing in the centers of other galaxies? Detailed observations of stars and gas clouds very near the centers of galaxies show that they are rapidly orbiting a very massive object that we can’t see.

Is the sun in the halo of the Milky Way?

Bottom line: The sun is about 1/3 the distance from the center of the Milky Way galaxy to its outer edges. It’s located in a smaller spiral arm, between two large arms, called the Orion Arm.

Is Earth destroyed in Halo?

The Insurrection and the Human-Covenant war

Over the next twenty-seven years, humanity would wage a brutal war for survival, losing hundreds of colonies, including all of the Outer Colonies in 2536; and on 31 August 2552, the UNSC’s largest military installation, the planet Reach, was destroyed by the Covenant.

How many stars are there in the Milky Way halo?

Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe.

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What population of star is found in the halo?

Population II stars are metal poor stars; they contain about 0.1 percent metals. They are found in the spherical component of the Galaxy (the halo and the bulge).

What are halo stars?

A stellar halo is an essentially spherical population of stars and globular clusters thought to surround most disk galaxies and the cD class of elliptical galaxies. … These ages are similar to those of bulge and globular cluster stars, meaning that stars in the halo were probably among the first Galactic objects to form.

What does the type of stars found in the halo and bulge indicate?

The bulge and halo of the Milky Way (and other Sa and Sb galaxies) are composed mostly of old stars. This indicates that the bulges and halos of spiral galaxies probably formed through the primordial collapse of individual gas clouds early in the history of the Universe.