Space has discovered the brightest exoplanet ever found – video – TV show

(Adnkronos) –
Discovered by the European Space Agency (ESA) and the brightest exoplanet ever found, Khufu is a hot exoplanet that behaves like a mirror. The European Space Agency announced today that data from the ESA Cheops mission has already led to the startling discovery that an extremely hot exoplanet orbits its host star in less than a day covered in reflective metallic clouds, making it the brightest exoplanet ever found. . Aside from the Moon, the brightest object in the night sky is Venus, whose dense cloud layer reflects about 75% of the sunlight. By comparison, the Earth only reflects about 30% of the incoming sunlight. In short, now, for the first time, astronomers have found an exoplanet that can match the brightness of Venus: the planet has been christened LTT9779b. New detailed measurements from the European Space Agency’s Khufu mission reveal that this planet reflects 80% of the light reflected from its host star. The high-resolution measurements by Khufu were a focused follow-up to the initial discovery and characterization of the planet in 2020 by NASA’s TESS mission and ground-based instruments such as the ESO HARPS instrument in Chile. The study of exoplanets – planets outside the Solar System – that orbit a star other than the Sun. The European Space Agency’s Cheops orbits above Earth. As of December 25, 2022, 55 exoplanets have been confirmed as habitable or Earth-like. Scientists point out that the size of the exoplanet discovered by Khufu is the size of the planet Neptune, which makes it the largest “mirror” of the universe we know today. Scientists explain that the reason for the high reflectivity of the exoplanet LTT9779b is that it is shrouded in metal clouds consisting mostly of silicates – the same material sand and glass are made of – mixed with metals such as titanium. “Imagine a world on fire, close to its star, with clouds of heavy metal floating above it, and raining droplets of titanium,” explains James Jenkins, an astronomer at University Diego Portales and CATA (Santiago, Chile). James co-authored a scientific paper describing the new research, published today in the journal Astronomy & Astrophysics. The part of the light that the object reflects is called its “albedo,” and according to the European Space Agency (ESA), most planets have a low albedo, because they have an atmosphere that absorbs a lot of light and because their surface is dark or rough. The exceptions tend to be frozen, icy worlds or planets like Venus that have a reflective cloud layer. LTT9779b’s high albedo came as a surprise to scientists because the side of the planet facing its star is estimated to be about 2,000°. Anything above 100°C is too hot for water clouds to form, but the temperature of the atmosphere for this planet must be very hot even for metal or glass clouds. “It was really a puzzle, until we realized that we should have thought of this cloud formation in the same way as the condensation that forms in the shower after a hot shower,” says Vivian Parmentier, a researcher at the Côte d’Azur Observatory. France) and co-author of this research. To heat up a steamy bath, Vivian explains, you can cool the air until the water vapor condenses, or you can keep the hot water running until clouds form because the air is “too steamy to hold anything more.” Similarly, LTT9779b can form metal clouds despite being extremely hot because the atmosphere is saturated with silicates and metal vapors. The European Space Agency’s Khufu satellite is also scanning space thanks to the sophisticated Italian “eyes” designed and built by Leonardo. The Khufu space telescope, commissioned by the Italian Space Agency, was actually designed at Leonardo’s factory in Campi Bisenzio (Florence), where engineers created and instrument specialist physicists and technicians according to the requirements set by INAF researchers in Padua and Catania (OAPD and OACT), in collaboration with the University of Bern.In particular, Leonardo, together with the contribution of SMEs, supervised the creation of the telescope’s optical system, based on mirrors It’s almost spherical, and collimator optics on the focal plane (mirror and lenses). Being bright isn’t the only surprising thing about LTT9779b, ESA continues. Its size and temperature make it called a “superhot Neptune,” but no other planet of this size and mass has been found orbiting its star. This means that it lives in what is known as Neptune’s “hot desert”. The diameter of the planet is 4.7 times the radius of Earth, and a year on LTT9779b takes only 19 hours. All previously discovered planets that orbit their star in less than a day are either “hot planets” – gas giants with a radius of at least ten times that of Earth – or rocky planets smaller than Earth’s radius. “It’s a planet that shouldn’t exist,” says Vivian. “We would expect planets like this to have their atmospheres blown away by their star, leaving behind barren rocks,” he adds. The lead author of the study, Sergio Hoyer from the Marseille Astrophysical Laboratory, comments: “We think that these metallic clouds help the planet to survive in the hot desert of Neptune. The clouds reflect light and prevent the planet from warming and evaporating. At the same time, they are very high. The metallicity makes The planet and its atmosphere are heavy and hard to blow away.” To characterize LTT9779b, the European Space Agency’s Khufu mission characterizes exoplanets observed when the planet moved behind its host star. Because the planet reflects light, the star and planet together send more light toward the space telescope before the planet is out of view than after it. The difference in visible light received before and after a planet’s occultation shows how much light the planet reflects. This design was based on Khufu’s accuracy and 24/7 coverage. “A precise measurement of the tiny change in signal from the planet-smashing star was only possible with Khufu,” says astrophysicist Hoyer. Maximilian Günther, Cheops project scientist at ESA, also notes, “Cheops is the first-ever space mission dedicated to pursuing and characterizing already known exoplanets. Unlike large survey missions focused on discovering new exoplanets, Cheops has enough flexibility to quickly focus on targets.” Interesting and achieving coverage and accuracy that we often can’t achieve any other way.” By observing the same exoplanet with different instruments, we get the full picture. “LTT9779b is an ideal follow-up target with the exceptional capabilities of the Hubble and James Webb Space Telescopes,” notes ESA Science Operations Scientist Emily Rickman. “It will allow us – he assures us – to probe this exoplanet in a wider range of wavelengths, including infrared and ultraviolet, to better understand the composition of its atmosphere.” The future for exoplanet research is bright, as Khufu is the first of three missions dedicated to exoplanets. In fact, the European Space Agency recalls that the Plato mission will join Khufu in 2026, which will focus on Earth-like planets orbiting at a potentially energetic distance from their star, and the Ariel mission will join the fleet in 2029 and will specialize. In the study of the atmospheres of the outer planets. —[email protected] (web information)

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