The discovery of this star is the result of many coincidences, which can be said to be extremely rare and not easy.
Because stars are spherical luminous plasmas condensed by gravity, they are essentially point light sources. Because its size is limited-it will collapse into a black hole if it is too big, and the light emitted is too weak for us to see.
There are more than 6,000 stars visible to the naked eye in the universe, all of which are close to us in the Milky Way, within thousands of light years.
With the help of astronomical telescopes, scientists can see stars farther away, but most of them are in the Milky Way, because the brightness of a single star is limited after all, and even the best telescopes are embarrassed. At present, the most powerful astronomical telescope can see the farthest star, which is about 1 100 million light years. A star farther away can only be glimpsed when its fuel is burned out and its brightness explodes into hundreds of millions of times that of a supernova explosion.
So how did Hubble see this star after 900 million years in BIGBANG? 65.438+029 billion light years, can you imagine seeing candles on the moon?
At this distance, even if it is as powerful as the Hubble telescope, the whole galaxy looks like a fuzzy dot, and the light of millions of stars is mixed together. However, between our earth and this star, there is a huge galaxy cluster WHL0 137-08, which forms a huge gravitational lens, which magnifies the light of distant objects by at least 1000 times or more, making this star appear directly on the ripples of the spatial structure.
This kind of ripple is optically defined as "caustics", which can provide the maximum magnification and brightness. Just like the ripple surface of swimming pool, it can focus bright sunlight on the bottom of the pool to form a bright spot.
This star was named Ellendale, which means "morning star" in old English. Its mass is estimated to be at least 50 times that of the sun, its brightness is several million times that of the sun, and it is comparable to the known largest mass star. In this photo, you can see that the faint red arc bisects the image from the upper right corner to the lower left corner. The three bright spots in the arc, with Ellendale in the middle, and the points on both sides are mirror images of the cluster.
It is worth noting that in 20 18, Hubble also discovered the giant blue star "Icarus" 9 billion light years away through a gravitational lens, which broke its own record this time.
Although it appeared 900 million years after BIGBANG, it is not the oldest known star. The oldest known star is only 190 light years away. It was discovered by Hubble in 20 13, nicknamed "methuselah" (the oldest person in the Bible), and its age is estimated to be about146.68 million years-because this value is uncertain,
So will there be planets around Ellendale, especially terrestrial planets like our earth, that will evolve into life?
This is also of interest to scientists, because they want to know whether Ellendale is the first third star we have discovered.
The Big Bang produced two substances, hydrogen and helium, and a trace of lithium. The first generation of stars formed is the third star family, without any metal elements-the metal here is not what we usually call "metal", and hydrogen and helium account for an overwhelming number in the universe, so astronomers regard all elements heavier than them as metals.
After the first generation of stars quickly ran out of fuel, synthesized other elements and produced heavier elements through supernova explosion, the second generation of stars was born in its ruins, forming a second group of stars with poor metal content. After burning and exploding, many heavy elements were diffused into the universe, forming the first group of stars, that is, stars with more "metal" content like our sun.
So if Ellendale is really the first third star we have discovered, then there will definitely be no planets around it-there are no heavy elements to build planets; Even the second group of stars is unlikely. The content of "metal" is too small, and at most some gaseous planets may be formed.
But if Ellendale is the first group of stars formed on the remains of other stars, there may be terrestrial planets around it and life may evolve. Avi Loeb, the head of the astronomy department at Harvard University, once published a paper, arguing that in the billions of years after BIGBANG, the temperature of the cosmic background radiation dropped to 100 to zero, so that any planet is within the livable range of life, and you can start biochemical activities-just like cooking jiaozi, whether you boil it or put it in water.
So are there planets around Ellendale? Unfortunately, Hubble telescope can't see it even if it tries to suck milk. At present, the Weber telescope, which will take over its work, has been deployed and will start working in June. Maybe we can explore it later. Even if it can see the planets around Ellendale, it is estimated that it can't confirm whether there is life on it, let alone intelligent life like us.
Human beings are doomed to be lonely, but what can we do? Squeeze together, we will fight and hurt each other. Maybe it's the same when aliens come, so let's stop speculating.