Andromeda galaxy has how many stars

We can easily see it with the naked eye since it has an apparent magnitude of 3. In fact, it is one of the few distant objects that we can see without using any optical aid. Not only is this galaxy large, but it is also very massive. Its diameter is around , light-years and its mass equals the mass of 1, billion Suns! There are about one trillion stars in the Andromeda Galaxy.

This spiral galaxy lies 2. Since it is easily visible to the naked eye on dark nights, the Andromeda Galaxy has been observed many times in the past. The earliest known record of this galaxy was that of Abd al-Rahman al-Sufi. He was a Persian astronomer around the 10th century. Simon Marius, a German astronomer, also gave it a description in the early s.

Before Andromeda became known as the spiral galaxy that we know it today, it was actually thought of as a nebula at first. This so-called nebula was thought to have been part of the Milky Way. At the time, it was believed that our own galaxy is the largest and that it contained everything in it. The first supernova observed outside the Milky Way was S Andromedae. Also, it remains the only supernova event that was ever observed in the Andromeda Galaxy.

It is also called Supernova after the year it was seen. At the time, the distance of the Andromeda Galaxy was not yet fully known. Charles Messier gave the designation M31 to Andromeda in And even by then, astronomers had given it some interesting descriptions.

One of the earliest photographs of Andromeda was taken by Isaac Roberts in For a long time, this galaxy was called the Great Andromeda Nebula. Because of this, the Great Debate was held to tackle the real nature of such an object and the universe as a whole. In , astronomers Harlow Shapley and Heber Curtis laid their facts to support their theories. This memorable event took place at the Smithsonian Museum of Natural History.

And because they are just within our home galaxy, they are relatively small when compared to the Milky Way. He compared different novae from the galaxy and observed that they are much fainter than the ones seen in other areas of the sky. This might mean that they are from somewhere farther than the Milky Way. The Shapley—Curtis Debate opened up different ideas and possibilities of the nature of the universe. Hubble was able to do so through Cepheid variable stars.

These pulsating stars can be used to measure the distance of objects. Through this, Hubble calculated the distance of the Andromeda Galaxy which is 2. Also, he was able to prove that the Milky Way is just one of the billions of galaxies out there. The most probable explanation of the origin of the Andromeda Galaxy involved a merger of protogalaxies. These primeval galaxies were smaller than Andromeda now. They probably collided and merged around 10 billion years ago.

During the time of formation, Andromeda most likely experienced a very high rate of star formation. This activity of stellar formation declined about 2 billion years ago to nearly a level of inactivity.

These concentrations are designated P1 and P2. P2, or the dimmer concentration, is situated at the center. It contains the central black hole in the galaxy. These two nuclei are 4. This discovery was made by a group of researchers headed by Robin Barnard of the Harvard-Smithsonian Center for Astrophysics. Images from different telescopes show that it has a normal spiral structure.

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Travel A road trip in Burgundy reveals far more than fine wine. Travel My Hometown In L. Subscriber Exclusive Content. Why are people so dang obsessed with Mars? By knowing the pulsation rate of a star and using some complex math, we can calculate its intrinsic luminosity of that star and its distance from the Earth. Edwin Hubble did just that, calculating the distance to astonishing 2. With the technological advancements over time, we were able to calculate something called transverse velocity, which indicates a colossal smash with our own galaxy in about 4 billion years.

A team of researchers at the Space Telescope Science Institute were able to create a computer simulation depicting the process and the result of this collision.

The results of these simulations were similar to those we observed in other galactic collisions, e. Less than a years after we proved it was, in fact, a galaxy, we were able to identify an exoplanet in the Andromeda galaxy. Given the diameter which is more than twice as long as in the Milky Way, we have thought it was at least twice as massive as our galaxy. But in , a group of researchers from Australia concluded that it might be as massive as the Milky Way, despite its size and number of stars.

In we observed a microlensing event, a type of cosmic event where excessive gravity bends the light and magnifies it to reveal otherwise obscure details. This allowed us to detect the first exoplanet in a distant galaxy that is approximately 6. Unlike other galaxies in our cosmic neighborhood that move away from us at an increasing rate due to the cosmic expansion, the Andromeda is set to collide with the Milky Way in about 4. This monumental collision will most likely result in a bigger spiral galaxy some 6 billion years from now.

The two supermassive black holes at the center of each galaxy will fall towards the center of the newly formed galaxy and merge to possibly produce a powerful quasar that shoots high-energy particles perpendicular to the plane of the galaxy.

The shock wave of the two black holes merging might cause an increase in new star formation. Whether the Solar system will survive this violent head-on collision is hard to calculate and predict. With the average distance between stars being billion times larger than the average size of a star, there might be some gravitational disruptions between the stars within the two galaxies, but direct collisions are unlikely. This means that our Sun will probably survive the collision.

Astronomy Day. The Complete Star Atlas. The Andromeda Galaxy is a giant swirl of around a trillion stars just down the street from the Milky Way. But billions of years from now, it will collide with our home galaxy. Newly forming stars glow fiery bright in this infrared image of the Andromeda Galaxy taken by the European Space Agency's Herschel spacecraft. The galaxy's spiral structure, which is similar to that of the Milky Way, will morph into one large elliptical galaxy once it merges with the Milky Way.

Fritz, U. Pietsch, MPE. If you look toward the constellation Andromeda on a clear night far from city lights, you can barely make out a long, fuzzy blob called the Andromeda Galaxy. However, the oldest known discovery of the Andromeda Galaxy dates to A. The great galaxy debate In the decades ahead, other astronomers started noticing supernovae exploding in Andromeda, too. One astronomer in particular, Heber Curtis, used the known brightness of these explosions to calculate the distance to Andromeda.

Billions of years from now, the night sky will glow with stars, dust, and gas from two galaxies: the Milky Way, in which we live, and the encroaching Andromeda Galaxy M Milkomeda: the Milky Way and Andromeda collide We now know the Andromeda Galaxy truly is an island universe distinct from our own. Snapshot : Hubble spies a galactic jack-o'-lantern. Arp 91 showcases a cosmic union in deep space. Neutron stars: A cosmic gold mine. What would this cyclic model of the universe mean for the Big Bang?

Snapshot : Looking at a peculiar piece of the universe.