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Thanks to missions like Gaia, we will take one step closer to a more reliable estimate of this frequently asked question: “How many stars are there in the universe?”
Are you one of those dreamers who watch the sky a lot and start counting the stars until they get tired or someone or something interrupts them? Have you ever wondered how many stars there can be in the sky?
According to astronomers, if you look at the sky on a clear day, you will see thousands of stars, around 6,000. But that’s only a tiny fraction of all the stars there; The rest is far out of your general field of vision.
It’s easy to ask the number of stars in the universe, but it’s hard to answer this question (NASA)The question that confused scientists
So; How many stars are there in the universe? According to The Conversation, it’s easy to ask this question, but it’s hard for scientists to give a fair answer. This question has intrigued scientists, philosophers, musicians and dreamers throughout the ages.
If we want to know the number of stars in the universe, we must first define the meaning of the universe, according to David Kornreich, an assistant professor at Ithaca College in New York state, told Space.com . The visible universe goes back in time about 13.8 billion years, and our universe may extend beyond this time, but we cannot see it, as some astronomers believe we can live. in a “multiverse” where there will be other universes such as ours contained in some sort of The greater entity.
Kornreich says that even if we limit the definition of the universe to the “visible” universe that we can see, estimating the number of stars within it requires knowing the size of the universe, and the size of the universe. the first complexity we are faced with here is that the universe itself is expanding, and the second complexity is that “space-time” can be folded.
Despite all of these complexities, this is perhaps the simplest answer to the question “How many stars are there in our universe?” This is about estimating the number of stars in a typical galaxy and then multiplying it by the estimated number of galaxies in the universe, but even that is difficult, and there are hurdles to overcome for the estimation. .
To calculate the number of stars in the universe, astronomers must first estimate the number of galaxies (NASA)number of galaxies
It can be said that the stars are not scattered randomly in space, but rather gather in large groups called galaxies, then before calculating the number of stars in the universe, astronomers must first estimate the number of galaxies.
They do this by taking very detailed photos of small portions of the sky, counting all the galaxies they see in those images, and then multiplying that number by the number of images needed to represent the entire sky.
In October 2016, a Science article suggested, based on deep-field images from the Hubble Space Telescope, that there were approximately two trillion galaxies in the visible universe.
The number of stars is an incredible number
Astronomers don’t know exactly how many stars there are in each of these two trillion galaxies, as most of them are very far apart, and there is no way of knowing exactly, but it is It is common knowledge that astronomers estimate the number of stars in the galaxy based on their mass, which has its own difficulties, as it has to filter out dark matter and the rotation of galaxies before making an estimate.
Some estimates suggest that the mass of the Milky Way contains 100 billion “solar masses”, or 100 billion times the mass of the Sun. By calculating the average of the types of stars in our galaxy, this gives a number of about 100 billion stars in the galaxy, and this is of course subject to change, depending on the number of larger and smaller stars. than our sun.
Using the Milky Way as a model, we can multiply the number of stars in a typical galaxy (100 billion) by the number of galaxies in the universe (2 trillion), and then we will find the answer to the number question. stars in the universe is a very astonishing number, because there are about 200 billion billion A stars in the universe, or 200 sextillion.
According to the Conversation website, the number is so large it’s hard to imagine; That’s about 10 times the number of cups of water in all of Earth’s oceans.
There are about 200 billion billion stars in the universe (NASA)Special missions to count the stars
Missions such as the Gaia space probe, which was launched by the European Space Agency in 2013 and is expected to operate until 2022, could provide more answers on the number of stars in the universe, as the Gaia mission aims to draw precise three-dimensional data. maps of about a billion stars in the Milky Way, or about 1% of the population of stars in the Milky Way.
According to the European Space Agency, Gaia will observe each of the 1 billion target stars an average of 70 times in 5 years, accurately plotting their positions, distances, movements and changes in brightness.
Taken together, these measurements will create an unprecedented picture of the structure and evolution of our galaxy. Through missions like this we will take one step closer to a more reliable estimate of this frequently asked question: “How many stars are there in the universe?”
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