At the recent annual meeting of the American Astronomical Society, NASA’s “Show” featured not only a new generation of exoplanet probeTess, but also two high school students. They were involved in Tess’s discovery of the first Earth-like habitable belt planet and the first planet to exist in a two-day system.
(Original title: NASA discovers first habitable planet: Earth-sized, or liquid water)
Journalist Yu Hanqi
Tess, whose full name is the Ling-Sun Exoplanet Survey Satellite, was launched in April 2018 to “connect” the Kepler space telescope as a planetary hunter. Specifically, Tess looks for planets by detecting light curves that change over time in star brightness. Once there is a “sun-ding” phenomenon, when a planet passes over the surface of a star, the star’s brightness decreases as if it were a solar eclipse.
The principle is intuitive, and the Kepler telescope used this method to find more than 4,000 exoplanets. However, in practice, there are still difficulties and miscalculations. Surprisingly, high school students can help solve these problems with NASA’s research team.
Double Day Glow
Wolf Cukier had just finished his senior year at Scarsdale High School in New York and went on a summer internship at NASA’s famous Goddard Flight Center.
He looked at all the data previously labeled “eclipse binary system” by volunteers. This is a system in which two stars rotate around each other, covering each other from an observational perspective.
Finding planets in a two-day system is more difficult than in a single-day system. Under the influence of two stars, the planet’s sun-ding phenomenon is irregular, in addition, “Tess” it is difficult to find the planet passing the smaller star.
This is a kind of current computer algorithm is not very good at the signal, but the human eye is more easily looking for clues. As a result, interns like Kukel need to check the data one by one.
About three days after the internship, Kukel noticed unusual signals in a two-day system labeled TOI 1338. This signal may at first look like a solar eclipse caused by a small star covering a large star, but it doesn’t happen at the right time. He reacted, it was actually a planet.
TOI 1338 Two-Day System
It was eventually confirmed that the TOI 1338 b is 1,300 light-years from Earth, 6.9 times larger than Earth, between Neptune and Saturn. Its two “suns”, one 10% larger than ours, and the other colder and darker, only one-third the mass of the sun.
Tess discovered the star TOI 700 100 light-years away in her first year of work and captured the multiple days of its three planets. Scientists initially thought it was much like our sun.
However, high school student Alton Spencer and several researchers found this to be a miscalculation. The TOI 700 is actually a smaller, cooler star with a mass and size of about 40 percent of the sun’s, and a surface temperature that is only half that of the sun.
After the parameters were corrected, the size and temperature of its three planets were significantly reduced accordingly. Scientists have found that the third planet on the periphery, TOI 700 d, suddenly fell into the habitable zone, meaning that temperature allowed liquid water to be found on it.
TOI 700 and three planets
Specifically, it is 20 percent larger than Earth, with a rotation period of 37 days, and receives 14 percent less energy from stars than Earth receives from the sun.