3. The ideal tracer would be in the outer halo, Bonaca notes, out beyond 300,000 light-years. The outer halo is thought to be slightly older, after all, and the most ancient galaxy clusters suggest that the Milky Way's building blocks began … That is because the center of the galaxy has a galactic bulge filled with stars, gas and dust — as well as a supermassive black hole. More because some massive objects do not emit light and, therefore, cannot be seen In the Milky Way's case, the number of stars is roughly 400 billion. Therefore we conclude that the gravitational mass is more than 10 times more massive than the luminous mass. Herschel reasoned that if the Milky Way was a sphere, we should see numerous stars in all directions. The Milky Way’s mass of 1.5 trillion solar masses is fairly normal for a galaxy of its brightness. No more than 30-50% of mass in the disk is DM, visible matter dominates. Most spiral galaxies show flat rotation curves out as far as we can trace them, even where no more stars are visible. that which we can see with the naked eye or a telescopes – makes up less than 10% of the mass of the Milky Way. Our galaxy is a whole lot bigger than it looks. The Milky Way is not wider than it's thickness. The Southern Milky Way is far more spectacular than the Milky Way that those of us situated north of the equator can ever see.
Mass of the Milky Way While dark matter dominates the universe, it's distribution within and around the Milky Way is more complicated. How do we know that there is much more mass in the halo of our galaxy than in the disk? In optical images, star view blocked by dust. False. There’s still work to be done, though. It's thought to be more diffuse than the visible matter, so that the disk is actually mostly baryonic mass.

The black hole has a mass of 6.5 billion suns, and it is as big as our whole solar system. Previously thought - 100,000 light years! In the case of our Milky Way Galaxy, we can see about 200 billion solar luminosities worth of light.

We know dark matter is there because of the rotation curve of the galaxy; if the mass was concentrated at the center, the velocity of the outer regions would be slower than the inner regions. The Milky Way is approximately 890 billion times the mass of the Sun. For now, astronomers know less about the shape and mass of the Milky Way than of many other galaxies.
The Milky Way is composed of three main parts: a central bulge, a relatively flat disk and a roughly spherical surrounding halo. Is there more or less mass in the Milky Way's disk and halo than we can see?

At all halo masses, there is a marked tendency for halos with higher spin to be in denser regions and thus to be more strongly clustered. In far IR (FIR), dust emission is dominating. That way we can't see a black hole, all we see is darkness. For a long time, we thought that Andromeda was larger, more … If the Milky Way were made of ordinary stars like the Sun, we would expect it to have roughly 200 billion … Select the correct statements. Taken from La … The Milky Way’s major mergers (in which the Milky Way accretes a smaller galaxy with mass greater than a tenth of the Milky Way’s) can deposit stars in our galaxy’s disk. The Milky Way is much wider than it's thickness. Explain your reasoning. Our Milky Way galaxy is a glorious beast, with several hundred billion stars moving together in the immense spiral disk that defines it. Black hole, bulge, disk and halo of the Milky Way. Stars in the outskirts of the Milky Way orbit the galaxy at much higher speeds than we would expect if all the mass were concentrated in the disk The Milky Way is the second-largest galaxy in the Local Group (after the Andromeda Galaxy), with its stellar disk approximately 170-200 000 light years in diameter and, on average, approximately 1,000 ly (0.3 kpc) thick. That means that all of the “luminous matter” – i.e. In the rotation curve decomposition in the Milky Way, the following components have been assumed : The central black hole with mass M BH = 4 × 10 6 M ⊙, An innermost spheroidal component with exponential-sphere density profile, or a central massive core, They found that there were more stars in the directions of the band of the Milky Way than above and below. If they exist, MACHOs are expected to be found only in the disk of the Milky Way, whereas WIMPs would be found only in the halo.

We also review recent observations and derived results. In the inner 20 kpc, stars more metal poor than [Fe/H]< 3 have less than 10 per cent chance, on aver-age, of being deposited from dwarf galaxies with lower mass than 107 M .