The newly discovered exoplanets turned out to be hot Jupiters. However, they are at least 10% larger than Jupiter.
Hot Jupiters are similar in characteristics to the mosta large planet in the solar system with an orbital period of less than 10 days. These exoplanets have very high surface temperatures. The reason is the very close rotation around their parent stars.
A group of astronomers led by Rosanna H.Tilbrook of the University of Leicester, UK, announces the opening of four new facilities of this type. The scientists used the NGTS group of 12 independently installed 20-centimeter Newtonian telescopes at the Paranal Observatory in Chile.
Researchers have identified transit signalsin the light curves of four stars during the observation campaign throughout the year. The planetary nature of these signals was later confirmed by follow-up observations from the South African Astronomical Observatory (SAAO) and by analyzing data from the NASA Transiting Exoplanet Survey Satellite (TESS).
Recently discovered exoplanets receiveddesignations NGTS-15b, 16b, 17b and 18b. All four objects are short-period planets (with an orbital period of less than five days) orbiting different G-type main sequence stars.
NGTS-15b with a radius of about 1.1 the radius of Jupiter isthe smallest planet from the newly acquired quartet. It is about 25% lighter in mass than Jupiter and orbits its host every 3.27 days at a distance of 0.044 AU. e. from him. The equilibrium temperature of the planet is 1146 Kelvin (872 ° C). The parent star, NGTS-15, belongs to the spectral type G6V, has a mass similar to that of the Sun, but about 5% less than it. Observations show that NGTS-15 is about 3.28 billion years old, has an effective temperature of about 5600 K (5,327 ° C), and is about 2,600 light years away.
Although NGTS-16b is the largest exoplanet about whichreported in the article, its mass is only 0.67 that of Jupiter. Its orbital period is 4.84 days, the distance from the star is 0.05 AU. That is, and its equilibrium temperature is at the level of 1,177 K (904 ° C). NGTS-16 is a G7V solar mass star with a radius of about 1.21 solar radii. The star is estimated to be 10.29 billion years old and has an effective temperature of 5,550 K (5,277 ° C). The planetary system is located approximately 2,900 light years from Earth.
NGTS-17b - the most massive exoplanet of the four recentlyopen, since its mass was calculated at about 0.764 times the mass of Jupiter. The planet is about 24% larger than Jupiter, and its equilibrium temperature is at 1,457 K. The results show that NGTS-17b orbits its 9.2 billion year old host every 3.24 days at a distance of about 0.04 AU. e. from the parent star NGTS-17. It is about 3,400 light-years from Earth, slightly more massive than the Sun, and has a radius of nearly 1.34 Suns. Effective temperature - 5 650 K (5 377 ° C).
Extrasolar planet NGTS-18b - the least massive of those described in the article.Its mass is only 0.41 that of Jupiter; however, it is about 21% larger than Jupiter. The exoworld is separated from NGTS-18 by 0.045 AU. That is, and it only takes 3.05 days to fully fly around its owner. The equilibrium temperature of this planet is estimated at approximately 1,381 K (1,108 ° C). As for the parent star of spectral type G5V, its radius is about 1.4 times the radius of the Sun, and its mass is similar to that of our Sun. The star is 10.8 billion years old, has an effective temperature of about 5,610 K (5,337 ° C), and the distance from it to Earth is 3,600 light years.
Taking all the results into account, the authorsThe articles concluded that three of the four recently discovered objects, namely NGTS-16b, NGTS-17b and NGTS-18b, are likely "inflated" exoplanets. Such planets have an extremely low density - less than 0.1 grams per cubic centimeter. The texture of these planets has been compared to cotton candy.
Ideal conditions for the origin of life found on the moon of Saturn
Oxygen will definitely disappear: what will happen to the Earth without the main source of life
Physicists have created an analogue of a black hole and confirmed Hawking's theory. Where it leads?
NGTS - Next Generation Transit Survey