What are the characteristics of Andromeda galaxy?

In the vast universe, there are stars of all sizes. What do you know about galaxies? Everyone knows a lot about the solar system and the Milky Way, so do you know the Andromeda galaxy? Next, we use constellation knowledge to look at the characteristics of Andromeda galaxy. Galaxy characteristics Andromeda galaxy approaches the sun at a speed of about 300 kilometers per second (per second 180 miles), so it is one of the few blue-shifted galaxies. Considering the speed of the solar system in the Milky Way, we will find that the speed of Andromeda approaching the Milky Way is100 ~140km/s (62 _ 87mph/s). Even so, this does not mean that it will collide with the Milky Way in the future, but according to the latest observation data of 20 15, the Milky Way may be approaching M3 1 at a speed of 200 kilometers per second. Even if there is a collision, it will be 3 billion years later (10). In this case, the two galaxies will merge into a larger galaxy. This kind of event often happens in galaxy clusters. At least three methods are used to measure the distance of M3 1. In 2004, the distance was estimated to be 251130,000 light years (7.704 million parsec) by Cepheid Variable Star Method. The distance of Andromeda galaxy is close enough to be estimated by the method of Red Giant Branch (TRGB). In 2005, the distance measured by this method was 2.56 8 million light years (7.85 2.5 thousand parsec). On average, the estimated distance of these measurements is 253 70,000 light years (775 22 thousand parsec). According to the above distance, the widest point of the diameter of M3 1 is estimated to be 220,000 4000 light years. The estimated mass of the Andromeda galaxy (including dark matter) is about1.23x10/2m _ (or1.23million solar mass), which is equivalent to the mass of the Milky Way (5.8x10/kloc-). Although the error range is too large to be completely confirmed, it can be confirmed that the mass of M3 1 is larger than that of the Milky Way, the volume of M3 1 is larger than that of the Milky Way, and it contains more stars than the Milky Way. M3 1 seems to have more ordinary stars than the Milky Way, and its estimated brightness is twice that of the Milky Way. However, the rate of star formation in the Milky Way is much higher. M3 1 can only produce 1 star with solar mass every year, while the Milky Way has 3-5 solar masses. The appearance rate of nova in the Milky Way galaxy is also twice that of M3 1. This shows that M3 1 has passed the stage of star formation, while the Milky Way is in the stage of star formation. This means that in the future, there will be as many stars in the Milky Way as those observed in M3 1.