0
Why do astronomers propose that the Milky Way Galaxy contains a lot of dark matter?
Wiki User
∙ 11y ago
Oh, well this is an interesting question, and a fun one to answer!
Basically, dark matter is proposed to exist because of the observations of interacting masses both within and between galaxies. (Note that it is not just the Milky Way that is proposed to contain dark matter; rather, 84% of the universe is hypothesized to be made of dark matter.) Basically, the total mass of all the stars and planets and other celestial objects should not be enough to cause the effects of gravitational lensing, solar revolution, etc. that are observed. Therefore, dark matter is proposed to exist; a type of matter that only interacts with gravitons and W bosons (only interacts with gravity and the weak force) and that is entirely undetectable.
Wiki User
∙ 11y ago
Add your answer:
Earn +20 pts
What is found in the Milky Way galaxy's galactic halo?
"The halo primarily contains individual old stars and clusters of old stars ("globular clusters"). It may be over 130,000 light years across. The halo also contains "dark matter," which is material that we cannot see but whose gravitational force can be measured." to shorten the answer - individual stars, clusters, and dark matter.
What have Astronomers have been unable to prove that what exist?
'Dark matter' and 'dark energy' have not been observed or proven yet.
Are there planets that life can be on in the Andromeda Galaxy?
The Andromeda Galaxy is the largest galaxy in the local cluster. This means that it contains more stars than the Milky Way and more stars mean more planets. Considering that scientist estimate that there could be thousands on planets with intelligent life in our own galaxy it would be logical to assume the same about the Andromeda Galaxy.
Is the sun matter?
Yes. In fact the sun contains the vast majority of the matter in the solar system.
What is the sun's period of revolution around the center of the galaxy?
The sun is one of hundreds of billion of stars in our galaxy, the Milky Way. The galaxy is composed of gaseous interstellar medium, neutral or ionized, sometimes concentrated into dense gas clouds made up of atoms molecules, and dust. All of the matter -- gas, dust, and stars -- rotate around a central axis perpendicular to the galactic plane. The centrifugal force caused by the rotation balances out the gravitational force, which draw all the matter toward the center. The mass is located within the circle of the Sun's orbit through the galaxy is about 100 billion times the mass of the Sun. Because the Sun is about average in mass, astronomers have concluded that the galaxy contains about 100 billion stars within its disk. All stars in the galaxy rotate around a galactic center but not with the same period. Stars at the center have a shorter period than those farther out. The Sun is located in the outer part of the galaxy. The speed of the solar system due to the galactic rotation is about 220 km/s. The disk of stars in the Milky Way is about 100,000 light years across and the sun is located about 30,000 light years from the galaxy's center. Based on a distance of 30,000 light years and a speed of 220 km/s, the Sun's orbit around the center of the Milky Way once every 225 million years. The period of time is called a cosmic year. The Sun has orbited the galaxy, more than 20 times during its 5 billion year lifetime. The motions of the period are studied by measuring the positions of lines in the galaxy spectra.
The Milky Way galaxy contains instellar matter may?
The Milky Way Galaxy contains interstellar matter that may form new stars.
Why do astronomers theorize that most of the matter in galaxies and clusters of galaxies is dark matter?
most of the mass in a cluster of galaxies is invisible, which provides astronomers with the strongest evidence that the universe contains a great amount of DARK MATTER
Why do astronomers theorize that most of matter in galaxies and clusters of galaxies is dark matter?
most of the mass in a cluster of galaxies is invisible, which provides astronomers with the strongest evidence that the universe contains a great amount of DARK MATTER
What do you know about dark matter?
Astronomers can infer the mass of a galaxy from the rate at which it rotates. The visible, glowing matter in galaxies (i.e., the stars) do not account for the amount of matter which we know must be there, hence we conclude that there is some additional matter which we do not see because it does not glow, or in other words is dark. Beyond that, we don't know very much about dark matter.
What is thev connection between universestar and galaxy?
The universe comprises all matter in space. This includes a very large number (200 billion to 2 trillion) galaxies. Each galaxy comprises a very large number of stars: our contains 100 thousand million stars.
Why do astronomers think there is dark matter in the universe?
That is because the dark matter attracts normal matter through its gravitation.
Why do astronomers study the sun?
There is an very dangerous matter in the sun named Black Matter. If the astronomers can get some of that matter, they can let a rocket fly to Jupiter and the austronauts will survive. Excuse me if my English is bad, I'm Dutch.:D
Why are most galaxies formed like a disk?
A galaxy is formed when a nebula collapses under the force of gravity of the matter that it contains. The process of collapsing imparts a rotational momentum to the galaxy. It is this rotational motion which gives galaxies their characteristic disk shape.
Where do matter come from?
It came from galaxy.
Does a baseball bat contain matter?
Yes, it contains matter. in this universe there will be no such a thing which does not contains matter
What was the basic idea about matter that leucippus and democritus propose?
eliot whalen
How could the astronomers from Cardiff University seen a galaxy made entirely of dark matter?
Dark Matter has yet to be actually "seen" by anyone, but its existence can be inferred using several methods, including gravitational lensing (effect on light produced by extreme gravity from galaxies and other celestial objects), and gravitational attraction, which can be observed and measured. The Cardiff team discovered in 2005 what they believe to be a Dark Matter Galaxy in the Virgo Cluster (VIRGOHI21). A mere 50 million light years away, it does not appear to have any visible stars, and it was observed using radio frequency observations of hydrogen. Based on subsequent galaxy rotation profiles, it is believed that the galaxy contains 1000 times more dark matter than hydrogen, and a total mass of about 1/10 that of the Milky Way, which is comprised of about 10 times more dark matter than ordinary matter. Theoretical models of the Big Bang and Large Structure Formation (observable distributions of matter and light on the largest scales (billions of light years) suggest that Dark Matter Galaxies should be very common, but until the Cardiff discovery, none had been actually observed.
