Recently, the old and strong Hubble telescope has exploded a big news, found a star with a light travel distance of 12.9 billion light years, that is to say, it appeared 900 million years after the big bang, what we see now, is an ancient star 12.9 billion years ago, so is there a planet around it? If there were An Earth-like planet like ours, would there be life on it?
The discovery of this star is the result of a lot of coincidences, which can be said to be extremely rare and very difficult.
Because stars are gravitationally cohesive spherical luminescent plasmas, essentially a point light source, because of their limited size — too large to collapse into a black hole , so a little farther away, the light emitted is too faint to see for us.
There are about 6,000 stars in the universe that we can see with the naked eye, all of which are very close to us in the Milky Way, about a few thousand light-years away.
With the help of astronomical telescopes, scientists can see farther stars, but most of them are in the Milky Way, because the brightness of a single star is limited after all, and even excellent telescopes are embarrassed, and the most powerful astronomical telescopes can see the farthest stars in about 100 million light years. A single star farther away can only wait until its fuel is burned out, and the brightness of the supernova explosion increases by hundreds of millions of times before it can be glimpsed.
So how did Hubble see the star 900 million years after the explosion? 12.9 billion light-years, can you imagine you seeing a candlelight on the moon?
At such a distance, even as powerful as Hubble, an entire galaxy looks like a tiny, blurry dot, with millions of stars' light mixed together. However, between our Earth and this star, a huge galaxy cluster, WHL0137-08, forms a huge gravitational lens, which magnifies the light of distant objects behind us by at least 1,000 times or more, allowing the star to appear directly on the ripples of space structure.
This ripple, defined in optics as "caustics," provides maximum magnification and brightness, like the rippled surface of a swimming pool, which can focus bright sunlight onto the bottom of the pool to form a bright spot.
The star, which has been named Earendel, means "morning star" in Old English, is estimated to have a mass estimated at least 50 times that of the Sun and is millions of times brighter than the Sun, rivaling the largest known mass star. In this photo you can see that the faint red arc splits the image bisected from top right to bottom left, with 3 bright spots in the arc, Erundel in the middle, and the spots on both sides are mirror images of star clusters.
It is worth noting that in 2018, hubble also used gravitational lensing to discover the huge blue star "Icarus" 9 billion light-years away, this time breaking its own record.
Although it appeared 900 million years after the Big Bang, Erundel is not the oldest known star, the oldest known star is only 190 light-years away, discovered by Hubble in 2013, nicknamed "Matusara" (the longest-lived person in the Bible), its age is estimated to be about 14.66 ±80 million years old – because this value is not certain, it can not be considered larger than the confirmed age of 13.77 ± 0.6 billion years, but it must have formed shortly after the Big Bang.
So could there be planets around Erundel, especially terrestrial planets like ours, that evolved life?
This is also of interest to scientists, who want to know whether Erundel is the first Tristigned star we have discovered.
The Big Bang produced two substances of hydrogen helium and trace amounts of lithium, and the first generation of stars formed was the Third Family star, without any metallic elements - the metal here is not the "metal" we usually know, and the hydrogen helium in the universe accounts for an overwhelmingly large amount, so astronomers regard all the elements heavier than them as metal.
After the first generation of stars quickly ran out of fuel, synthesized other elements and exploded through supernovae to produce heavier elements, the second generation of stars was born in their ruins, forming a second family of stars with poor metal content. Then it burned and exploded, spreading many heavy elements into the universe to form the first family of stars, that is, stars with more "metal" content like our sun.
So if Erundel is really the first third star we found, there will certainly be no planets around - there are no heavy elements to build planets; even second stars, it is estimated that it is unlikely, the "metal" content is too small, may form some gaseous planets at most.
But if Erundel was the first family to form on the remnants of other stars, there could be terrestrial planets around them and evolve life. Avi Loeb, former head of Harvard University's department of astronomy, once published a paper arguing that in the billions of years from about 17 million years after the Big Bang, the background radiation temperature of the universe was reduced to between 100 degrees and zero degrees, so that any planet was within the habitable range of life and could begin life chemical activity - just like you cook tangyuan, whether you boil the water and then put the tangyuan down, or cold water will go down the tangyuan, the temperature on the surface of the tangyuan must be the "iron pot" background radiation temperature - and the water temperature is the same.
So are there planets around Erundel? Unfortunately, hubble telescopes can not be seen even with the strength of milk, and the Weber telescope that is currently working on it has been deployed and will begin work in June, which may be explored in the future. Even if it could see the planets around Erundel, it would be impossible to confirm whether there was life on them, let alone intelligent life like ours.
Human beings are destined to be lonely, but what can be done? Huddled together and fighting, hurting each other, aliens may be the same when they come, let's stop guessing.
Stay tuned: