The astrophysicists Prof. Avi Leib and Prof. Dan Maoz from Tel Aviv University and Harvard University estimate that it will be possible to locate planets orbiting white dwarfs with the technology expected to come into use in the next decade
Even dying stars may still host life-bearing planets – and if such life exists, we may find it within the next decade. This is according to a theoretical study of Earth-like planets orbiting white dwarfs.
The researchers found that oxygen can be detected in the atmospheres of planets orbiting white dwarfs much more easily than on Earth-like planets orbiting a Sun-like star.
In the search for alien biological signals, the first stars we need to investigate will be white dwarfs" say Prof. Avi Leib and Prof. Dan Maoz from Tel Aviv University and Hardward University. The article published this week in the journal of the British Royal Astronomical Society.
When a star like our Sun dies, it ejects its outer layers into space, leaving behind a hot core known as a white dwarf. A typical white dwarf is about the size of Earth. It cools slowly and dims over time, but it can retain heat long enough to warm a nearby world for billions of years.
Because white dwarfs are much smaller and fainter than the Sun, the planet would have to be much closer to be in the habitable zone, meaning a place where water on the planet's surface is in a liquid state. A habitable planet may orbit the white dwarf every ten hours at a distance of about one and a half million kilometers (XNUMX percent of the distance between the Earth and the Sun).
Before a star becomes a white dwarf, it swells and becomes a red giant, at which point it swallows the nearby planets and destroys life on the rest of the planets. Thus the planet should reach the new habitable zone after the star has become a white dwarf. The planet can develop from remnants of dust and gas, thus becoming a second-generation world, or it can migrate in from a greater distance.
If there are planets in the habitable zone of a white dwarf, we will need to find them before we can study them. The prevalence of heavy elements on the surface of white dwarfs indicates that a significant proportion of them may contain a system with rocky planets. Leib and Mouz estimate that a survey of the 500 closest white dwarfs may yield at least one terrestrial planet in the habitable zone.
The best approach to finding such a planet is to look for eclipses - that is, to look at a star that dims when the planet passes by it and blocks a significant part of its light, thereby indicating its existence.
More importantly, we can only study the atmospheres of stars transiting their suns. When the white dwarf's light shines through the ring of air surrounding the planet's disk, the atmosphere will absorb some of the sunlight. This is enough to detect chemical fingerprints that will show us whether this air contains water vapor and perhaps even signs of life such as oxygen.
Astronomers are particularly interested in finding oxygen because the oxygen in the Earth's atmosphere originates from the process of photosynthesis by plants. If all life ceased on Earth, our atmosphere would quickly be depleted of the oxygen that would dissolve in the oceans and oxidize the surface. Thus the presence of large amounts of oxygen in the atmosphere of a distant planet may indicate the existence of life on its surface in real time.
The James Webb Space Telescope, which NASA plans to launch at the end of the decade, is expected to allow us to detect gases in such distant worlds. Leib and Mouz simulated data that the James Webb Telescope would see if it probed a populated world orbiting a white dwarf. They found that both oxygen and water vapor would be detectable within a few hours of observation. "The James Webb Space Telescope is our hope for finding life-bearing planets in the near future," says Maoz.
"Although it is possible that the nearest life-bearing planet orbits a regular star, the first planet to be discovered with evidence of life may orbit a white dwarf, and this is based on existing technology and that expected in the coming years.
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A lot can be said, maybe yes, maybe not, but you'll just love it, for sure.
"Where is it simpler for life to develop?" - fuss in clothing.
Do you think life "just" evolved? Pay attention (and grow a brain): I (not Emmanuel) do not claim that there is a God. I'm not saying I agree with him either. But I do imply here (in response) that life is a little more than simple. And the evolution of this is not simple at all. In fact it is as simple as Kim Jong's military parade.. On.
But Emmanuel..
What you are suggesting is an extreme/threshold option.
You talked about probability and statistics..
Where is it simpler for life to develop?
In a planet that is more like us or more different from us?
What reason do you have to look for life on different stars when you haven't covered the similar stars yet?
You know that everything marked in blue and white or red and yellow is prohibited in the parking lot, now you found some sign that says "parking is allowed from 12 at night to 8 in the morning" despite this familiar color, so what?
So now will you start looking for parking in blue white and red yellow with billboards or will you look for the clean and good gray and only then start looking for uncommon/known combinations?
For the deer, where I wrote that hydrogen is a liquid, I wrote nitrogen, not hydrogen
I wrote that the hydrogen is a gas and the nitrogen is the liquid
It's not about faith, it's about statistics and probability
If life here was formed randomly it is possible to easily build life at different temperatures and with different compositions of building blocks of life
If humans think that the only form of life is the one suitable for the earth, it is just like humans thought a thousand years ago that the earth is in the center
I don't know if you know, but there is an underground water reservoir near Nesher factory that has no sunlight
And wonder and wonder there is life there!!!!
If the earth has such strange things, imagine how big the universe is and how strange things can be
Because of people like you, humanity thought for 20000 years that the world is flat and the sun goes around the earth and the earth stands on three elephants
There is no exit from the square here
If life here arose randomly as science hypothesizes then it could also arise in completely different environments
Does anyone know if it is possible with the current Spitzer Space Telescope to observe white dwarf planets, and get information about their atmosphere?
I'm sure I'm not the only one who is already dying to look at this information, and "his telomeres are getting shorter"...
To Emanuel
First we look for what is inside the square
You only leave the square if you have no choice
Emanuel,
It is clear to everyone that there may be a different life from the life we are familiar with on Earth. The problem is that what you propose does not allow for scientific research. When looking for a life similar to God's, you can make predictions - you can expect certain processes that will leave traces that can be discovered. It can be said that in a star with characteristic temperature X and composition of the atmosphere Y, we also expect to find molecules of type Z because given such an atmospheric composition - these are the products of the processes that will allow life.
To say that there can be strange things is not enough.
The hydrogen in (90-) is not water (by the way, it is still a gas) - since not every liquid is water in terms of chemical properties and an acidic sea impairs the ability to create complex structures - you must propose how exactly this enables complex processes necessary for life.
There can always be complicated things that we don't know, science is full of countless examples of discoveries that don't exist in everyday life that were made from theory only and were only later confirmed by observation, but we need to suggest how they work and how evidence can be found for this. Otherwise, it is not science but faith.
Why does everyone think that in order to find a star that has life on it there must be oxygen or an environment similar to Earth
Think about living at a temperature of minus 90 degrees where the nitrogen is the water
Hydrogen is the gas we breathe
Think of a world whose sea is generally an acid dangerous to humans
Gentlemen, leave the square
The universe can build itself life forms that even our wildest imaginations cannot imagine
Curious…
I wonder what the developments will be on the subject...
It should be "...Prof. Avi Leib from Harvard University and Prof. Dan Maoz from Tel Aviv University..."
"Our atmosphere will quickly be depleted of space"
fix oxygen
fixed.
In the title "evidences" may and "may not". The issue in the trial is the evidence and not the life.