Have you ever looked up at the starry sky at night and wondered “How many stars are in the Milky Way?” If not, we will (try to) answer.
How many stars does the Milky Way have? Astronomers cannot be sure of this number because not all stars in the Milky Way are visible from Earth, due to some being too distant, too faint, or obscured by gas or dust.
However, there are various estimates: some based on the shape and size of our galaxy, others on its likely mass. These estimates typically range between 100 and 400 billion stars. For comparison, 100 billion is roughly the total number of people who have ever lived on Earth, according to Science Focus.
Is it possible to know for sure how many stars the Milky Way has?
According to Jos de Bruijne, a European Space Agency (ESA) researcher working on the Gaia mission, the current estimate is between 100 and 400 billion stars. De Bruijne stated for Space.com that getting an accurate number will be difficult.
The Gaia mission, which has been in orbit since 2013, has managed to map the positions of 1.7 billion stars in the vicinity of the Sun, up to a distance of 326 light-years. Although astronomers could extrapolate this data to model the entire galaxy, even Gaia has difficulty seeing the faintest and smallest stars, making the results not entirely accurate.
“The fundamental problem is measuring the luminosity distribution for very faint red dwarfs and extrapolating to the gray dwarf limit,” said de Bruijne.
What do we do with the double stars?
Red dwarfs are the most common stars in the Universe and also the longest-lived. However, due to their low brightness, they are sometimes difficult to detect. Gray dwarfs are even less luminous. These are basically “failed” stars that have not accumulated enough mass to trigger nuclear fusion in their core. They are therefore something between a star and a planet, which makes them even harder to observe than red dwarfs, especially at great distances.
“Another complication is the presence of binary stars, whose frequency is still not well characterized,” added de Bruijne.
De Bruijne expects that by the end of the Gaia mission in 2025, scientists will have a somewhat clearer idea of the number of stars in our galaxy, but “significant uncertainties will likely remain.”
We recommend you also read:
General culture test. What was the Bing Bang?
A team of astronomers would have solved the mystery of the age of the Milky Way! How old is our galaxy?
How did the basic elements of life get to Earth?
NASA offers $3 million to solve huge problem with Moon missions
Source: www.descopera.ro
