Galaxies

The Milky Way Galaxy is the second largest galaxy, after Andromeda, in the Local Group. The Triangulum Galaxy (a.k.a., the Star Wars galaxy) is the third largest.

The Local Group contains about 30 galaxies, including dwarf galaxies.

Stars in the middle of galaxies are usually found in the galactic disk, where there is a higher concentration of gas and dust that is conducive for star formation. Stars on the outside of galaxies are often located in the galactic halo, which is a more diffuse region that contains older stars and is further away from the dense center of the galaxy. The distribution of stars within a galaxy is influenced by factors such as gravitational interactions and the history of star formation in that region.

it has existed since the beginning of life no one crated earth as far as we know it.

Far or near, all galaxies were thought to be formed in the first half billion years of the formation of the universe ... that is, about 13 billion years ago.

Note that we're seeing the distant ones in a younger stage of development.

Andromeda was the daughter of Cepheus and Cassiopeia in Greek mythology.

NGC 3370 is a barred spiral galaxy in the constellation Leo. It contains stars, gas, dust, and possibly planets within its structure. Comets are not typically found within galaxies, but rather in the outer reaches of the solar system.

The teacher's manual answer is that mass warps space. But the real answer is "Just Because" it's what mass does. == It's interesting in this day and age when we're on the threshold of discovering the very basic nature of the universe by virtue of our understanding of matter and spacetime that we don't know more about gravity. For as long as I can remember, the best answer for the question "what is gravity?" is this one: We don't really know. It's still true. Accept it. Say it with me: we don't really know. See? It didn't stop working just because we made that admission. We know what gravity does. There is a wonderful history associated with its quantification. We can sure measure its effects, can't we? Those elegant sets of calculations for, say, the music of the spheres, are nothing short of breathtaking. But what is it that is accessible to the rest of us that lets us get a handle on gravity? There really isn't too much. Let's review. Matter has mass and occupies space. By virtue of just existing, matter warps spacetime. It puts a dent in it. But that doesn't provide too much extra help. Spacetime is (hold on to your seat) a mathematical construct. Darn it! That ain't any help! Perhaps an experiment would help. Try something that's been passed along to teachers here and there. The necessary equipment list includes a bed sheet and two modestly heavy balls like croquet balls. Lighter balls like tennis balls won't work as well, but a bit of creative thinking and experimenting will allow one to make a good substitute for the wooden spheres. Four students hold a bed sheet by the corners and stretch it out. Hold it steady! Put a ball in near the middle. See the dent? That's what mass (the ball) does to spacetiime (the sheet). This is a two-dimensional model, but it is really quite good. Now add the second ball near the first one. (A bit of practice might be required because there are limits on what the bed sheet will allow. Try short sheeting the setup from one or from two adjacent sides.) The second ball makes a dent like the first one, but the space between them is deformed, and the balls will roll together. If they are placed too far apart, the demonstration breaks down, but that's where the practice comes in. Lastly, it's absolutely wonderful and exciting that we don't know more about gravity! We know all this other stuff. All this other science and technological stuff. And yet here is gravity! It is so big, so broad in its effect, that it is the large scale organizer of the whole universe itself! We have spent our entire lives in it, and we react to it without thinking when we move. And yet it stands in defiance of our understanding! Hey! Anybody wanna Nobel prize? Wanna become world famous? Wanna have hotties asking you for your phone number? We have this little problem that needs solving....

Nebulas are found in all types of galaxies, including spiral galaxies like the Milky Way, elliptical galaxies, and irregular galaxies. They are regions of dense dust and gas where new stars are formed. The variety of shapes and sizes of nebulas contribute to the diversity of galaxies in the universe.

Lunar mare

A person who studies planets and galaxies is called an astronomer. Astronomers observe and analyze celestial bodies such as planets, stars, and galaxies to understand their composition, behavior, and evolution. They use telescopes and other instruments to gather data and make scientific discoveries about the universe.

The diameter of the Milky Way galaxy is about 100,000 light-years. If the Sun and Earth were at the edge of the disk, we would still be within the galaxy's boundaries, so the diameter would remain around 100,000 light-years.

Both comets and Earth are celestial bodies located in our solar system. Comets are composed of ice, dust, and rocky material, similar to the materials present on Earth. Additionally, both comets and Earth experience gravitational forces from the sun that affect their orbits and movements.

They can merge, to combine into a single, larger, galaxy. Or, they can separate again.

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"Collide" is a misnomer because of the vast distances between stars in a galaxy, the odds of a stellar collision are extremely small.

The Andromeda Galaxy and the Milky Way Galaxy are on a collision course. If you're around when they begin to "collide" in about 4-Billion years, don't expect to see any fireworks in the sky. Except for an increase of the number of observable stars in the night sky, it will largely be a non-event.

No, although it could be recognised as going in 11 remainder 4 times, or 11 and 2/3 times

Yes, galaxies at very large distances can appear distorted due to gravitational lensing effects caused by the bending of light by massive objects. This distortion can elongate or warp the images of distant galaxies, altering their perceived shapes.

You are looking at the light that that star made 10 billion years ago. Since it takes that many years for the light to reach earth, you would not notice if that star died for 10 billion years, just like you wouldn't notice by looking at it that the sun suddenly died for 8 minutes (The amount of time it takes for its light to reach the earth). We are constantly looking at the sun 8 minutes ago!

The recessional velocity of a galaxy at a distance of 1 billion light years would be calculated using Hubble's Law by multiplying the Hubble constant (H0) with the distance.

Recessional velocity = H0 x distance = 22 km/s/Mly x 1,000 Mly = 22,000 km/s

Therefore, the recessional velocity of a galaxy at 1 billion light years would be 22,000 km/s.

That sounds like the Magellanic Clouds. Two galaxies that are satellites of our galaxy, visible in the Southern Hemisphere. They may be confused with clouds, but they are always in the same part of the sky (including in the apparent rotation of the sky around the Earth, of course).

This type of galaxy is categorized as a spiral galaxy. The bulge at the center contains older stars, while the spiral arms consist of younger stars and gas and dust regions where new star formation occurs. The Milky Way is an example of a galaxy with a bulge and spiral arms.

Yes, the Saptarishi are a group of seven prominent stars in Hindu astronomy that are part of the Ursa Major constellation. The Saptarishi are believed to be seven sages who are a vital part of Hindu mythology and are associated with guiding principles in Hindu cosmology.

Yes, this is due to the redshift effect in cosmology where the wavelength of light from distant galaxies is stretched as the universe expands, causing the light to appear redder. This redshift is proportional to the distance of the galaxy, helping astronomers estimate how far away it is.

Yes its called the Local Cluster or Local Group, we have many minor Globular or Cluster Galaxies orbiting our own.