Telescope searching for treasure unearths giant planet
A giant planet shrouded in clouds, in orbit around a star 385 light years from our sun, has been captured by the James Webb Space Telescope in images described as a ‘‘transformative moment for astronomy’’.
In observations led by a British astronomer, the pioneering telescope focused on a ‘‘gas giant’’ planet called HIP 65426 b, in a search likened to treasure’’.
It captured images in infrared light, which allows astronomers to more precisely calculate the mass and temperature of exoplanets – the term for planets in orbit around other stars. It should ultimately allow them to detect clouds moving across their surface, revealing alien weather on worlds hundreds of light years from our solar system. The images show the planet as ‘‘blobs of ‘‘digging for space light’’ in blue, purple, yellow and red hues under various infrared wavelengths.
The planet is up to 12 times bigger than Jupiter and orbits about 100 times farther from its host star compared with the Earth’s distance from the Sun, making it easier for astronomers to separate the planet from its star when capturing images.
The planet is only 15 to 20 million years old, a fraction of the age of the
Earth, which is 4.5 billion years old. Like Jupiter and Saturn, it has ‘‘no rocky surface and could not be habitable’’, Nasa said.
‘‘This is a transformative moment, not only for Webb but also for astronomy generally,’’ said Sasha Hinkley, associate professor of physics and astronomy at the University of Exeter.
More than 5000 exoplanets have been discovered in other star systems, including one in another galaxy, but only 20 exoplanets have ever been directly captured in images before, usually from groundbased telescopes which experience interference from the Earth’s atmosphere.
The existence of an exoplanet is usually detected when the light from a distant star appears to dim at regular intervals, suggesting that a planet is passing across its face once per orbit like a tiny partial eclipse.