Search for extraterrestrial life

Recently, researchers have assumed that looking at Earth is the same way that we are observing planets other than the Solar System (also called exoplanets).

Illustration. That could improve your chances of discovering organisms in distant worlds. How to find exoplanets Since 1999, a process of detecting exoplanets called the transit method has found thousands of other worlds by measuring the brightness of the stars that these planets orbit around. No one knows if these planets have any life, but if scientists observe the Earth using this method, they will probably detect signs of life. Once those signs are identified from Earth observations, experts can then find similar clues in the exoplanets. Scientists have recently described this approach as a mission called the Earth Transit Observer (ETO). This year, they presented this at the 52nd Moon and Planetary Science Conference. Most of the exoplanets we know of are found by transit, according to the US NASA Space Agency. Modern telescopes such as the Kepler Space Telescope and the Exoplanet Survey Satellite (TESS) can detect exoplanets when the path of a planet dims a star’s light overnight. slice. This is true even for stars thousands of light-years away. Scientists can estimate the magnitude of a planet based on the amount of light it is blocking and calculate the size of its orbit. The size and temperature of a host star as well as the distance between the planet and the star will provide additional clues as to whether exoplanets have life or not. The measure of transit can also hint at an exoplanet’s atmosphere. During a transit, a star’s light is filtered through atmospheric molecules. This could help researchers identify elements like oxygen and methane there. Such signs are often so small that astronomers need more transit observations to confirm the existence of these elements – according to a statement by the scientists. However, other factors on exoplanets and stars can affect the reading of molecules in the atmosphere. For example, planets change with the seasons, weather patterns and ocean currents. In addition, the activity of the Sun, such as the rise and fall of the solar wind, and the formation of solar storms also change. Any of these conditions can shape the behavior of the atmosphere, thus potentially affecting the proportion of molecules and elements in their atmosphere. Illustration. Finding “New Earth” Lead author Laura Mayorga of the planet-finding mission article in the Journal of Planetary Science says that, to understand those variables, “you need to know your stars as well as predict your planets. what do you look like ”. This can be a challenge when both the stars and the exoplanets are alien. “This is a very difficult problem,” says exoplanet astronomer at Johns Hopkins University’s Applied Physics Laboratory in Laurel Maryland (USA). Luckily, scientists already have all of those answers for a pair of inhabited planets and stars. That is our Earth and the Sun. For the ETO mission, a small satellite with a device capable of imaging near-violet to near-infrared light spectrum will observe the Earth as it passes in front of the Sun. The spectrophotometer will check for water and carbon dioxide markers as well as biological markers – oxygen and methane, ozone and methane. Besides, it is to point out the favorable conditions for life (of course, also to see if the signs are unique to Earth or not). The transit technique used in such an investigation would be similar to the technique used by the James Webb Space Telescope (JWST) to study some of the thousands of exoplanets, scientists say. know moving through their host stars ”. Since we all know the climate change on Earth and the patterns of the Sun’s activity, scientists can observe how they affect the reading of atmospheric molecules and then apply them to our observations. close to the “new Earth”. “The Solar System is the only place where we know all the answers. We can test our technique, point out limitations and make a connection between the results, ”said Mayorga in the statement -“ Then we can connect that with Unanswered observations from exoplanets ”. Scientists plan to submit the ETO proposal to NASA’s Astrophysical Pioneer Program in the fall of 2021.