After last year’s discovery of a Jupiter-like exoplanet orbiting a its host star HIP 11915 about 200 light-years from our planet, scientists have just detected another Jupiter doppelgänger dubbed Kepler-167e more than 1,000 light-years away.
Finding planets that are similar in size, mass, and orbit to Jupiter is crucial for the understanding of how our own solar system’s works. But Kepler-167e’s mass remains largely a mystery.
The newly-found exoplanet was spotted using Kepler space telescope. Kepler looks at the night sky and seeks stars that temporarily change the intensity of their light.
Scientists explained that when a star’s brightness diminishes it may be a sign that there’s a huge object blocking its light from reaching us, such as a planet. This was the case with Kepler-167e’s star, Kepler-167, which is less massive and cooler than our star.
According to the team that made the discovery, though its star is not as bright as the Sun, Jupiter’s twin receives the same amount of heat as Jupiter since its orbit brings it closer to its host star. Researchers believe that it may even have the same surface temperature as Jupiter.
The exoplanet is roughly the same size as Jupiter: about 81,000 miles across compared to Jupiter’s 86,000 mile-width. Nevertheless, astronomers aren’t yet able to calculate the mass of the mysterious planet. The team explained that Kepler’s data doesn’t provide enough hints for that.
For example, Kepler measures the changes brought to a star’s brightness when a planet in its system happens to get between the star and our telescopes. The dips in starlight can tell scientists a lot about the planet’s size and orbit.
Scientists can estimate how large the star is by calculating the amount of blocked light. They can also tell how much time the exoplanet needs to orbit the star. When Kepler-167e crossed its host star, Kepler noticed a dip in starlight of 1.6 percent. That percentage was used to calculate the planet’s approximate size.
But the mass of an exoplanet remains largely a mystery since its size is not influenced by the mass, i.e. Jupiter’s twin could be as large as Jupiter but 50 times more massive. Scientists could calculate the mass if they had spectroscopic data on the star.
The research team explained that as the exoplanet gets closer to its host star, the star’s light red and blue changes. But measuring those changes could take years because Kepler-167e needs 1,071 days, or nearly three years, to complete an orbit.
What’s amazing about Kepler-167e is that it is located in a planetary system inhabited by three other planets known as Super-Earths, which orbit Kepler-167 dangerously close and so they must be very hot.
Image Source: Pixabay