A new mission advances an in-depth exploration of planets outside the solar system
NASA's Kepler satellite mission is a huge success. Thanks to her, thousands of candidates for the title of outer planets were discovered - planets that do not orbit our sun, but other stars - and more than 100 of them have already been verified. Many of them are close in size to Earth: the 25 outer planets with the smallest diameters discovered to date have all but one been discovered by the Kepler satellite. There's just one small problem with the mission's fine crop: these planets are hundreds or even thousands of light-years away, too far for careful study.
This is where TESS, the satellite for mapping eclipses of outer planets, comes into the picture. NASA approved its launch in 2017, at a cost of 200 million dollars. The TESS satellite will scan a much larger area of the sky than its predecessor, giving up a new population of closer exoplanets that scientists can scan with future telescopes. "In total, we will examine about half a million stars," says TESS principal investigator George R. Ricker, an astrophysicist at the Massachusetts Institute of Technology (MIT). Thousands of these stars are within 100 light years or less of our solar system.
Similar to Kepler and the European satellite CoRoT that preceded it, the TESS satellite will look for anomalies: a brief dimming of the light coming from the star, at regular intervals, which will reveal the passage of the planet across the surface of the sun it orbits, a dimming that cannot be seen in any other way. Ricker estimates that TESS may discover about 500 to 700 planets, ranging from Earth-sized to several times larger, a handful of which may be suitable for life.
By the time TESS completes the list of the nearest exoplanets, at the end of the two years assigned to the mission, astronomers may have a new and sharp eye in the sky, with which to examine the new worlds in detail. NASA's James Webb Space Telescope (JWST), scheduled for launch in 2018, should be able to detect signatures of certain molecules in the atmospheres of nearby exoplanets. Signatures of this type could eventually be used as a tool to draw conclusions regarding the existence of life on such planets. In imaging experiments using JWST's detection power on a nearby exoplanet that may have life on it, "we can almost, but not quite, see signatures that are biological in origin," Ricker says. "We may well have to wait for a next-generation device in space to do this."
Regardless, if TESS does manage to locate hundreds of nearby planets, astronomers will have full employment for the foreseeable future: discovering more about these planets and the habitats they might support, and perhaps sending some future research spacecraft to a particularly interesting world.
The article is published with the approval of Scientific American Israel
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Haim Mazar,
I also see how conventions that were accepted in the past by scientists or famous people in a certain field, change over time thanks to new discoveries.
The question is whether these conventions were really based on science, or just a personal interpretation of a renowned scientist in those days?
I will give an example from today: "Stephen Hawking warns against sending radio signals into space to contact extraterrestrial civilizations, as he believes they can be aggressive."
We all respect Stephen Hawking's opinion, and recognize his contribution to science, but how exactly is his understanding of astrophysics related to the psychology of other cultures? What is the scientific basis on which he rests his argument?
And let's not mention his decision not to visit Israel...
It is very possible that in the future they will look at this sentence and say, for one reason or another, how stupid it was for our contemporaries to think that way...
But the point is that his argument has no scientific basis despite his status. Therefore, arguments such as scientific ones that have been proven otherwise should not be considered.
bsnow
The concept I propose has nothing to do with distance. It is a methodological tool for future days. In fact, it can be applied to the solar system already today. Bodies in the solar system that, according to estimates, are likely to contain life are Mars, Jupiter's moon Europa and Saturn's moon Enceladus. These bodies will serve as a means of confirming or refuting different models for them. As for the future, it should be taken into account that there will be scientific and engineering breakthroughs (which is what happens in other fields) that will shorten flights to those planets for short periods of time. I am convinced that you will say blessed is the believer. To deepen knowledge in the field, I recommend Thomas Kuhn's book "The Structure of Scientific Revolutions"
It still doesn't solve the distance problem
At this pace of discoveries, one can already expect the development of a new subfield in astronomy, astronomers whose specialty is the detection of new planets and their geological and climatological observations. A strong enough base for building models of planets and relying on these models to build different biological characteristics.