‘Historic’ James Webb images show exoplanet in unprecedented detail | James Webb Space Telescope

Unprecedented observations of a planet outside our solar system have revealed a burning gas giant shrouded in dusty red clouds.

The sightings, which astronomers say is a “historic moment for astronomy”, are the first direct images of a planet outside our solar system, which NASA has spent $10 billion (£8.65 billion) on. James Webb Space Telescope. They are also the first images of an exoplanet using infrared light, which will provide more precise information about the planet’s mass and temperature, and will allow astronomers to detect the movement of clouds drifting across the planet’s sky.

“This really is a historic moment for astronomy,” said University of Exeter astronomer Professor Sasha Hinkley, who led the observations. “James Webb will open the door to an entirely new class of planets that are completely inaccessible to us, and by observing them at a wide range of wavelengths, we can study their composition more deeply.

“We will be able to detect the presence of air.”

Direct imaging of exoplanets is a major technical challenge because the host star is much brighter. HIP 65426 b, the focus of the latest observations, is a gas giant about 5 to 10 times the mass of Jupiter at 385. light year From the ground Centaur constellation.

It is about 100 times Earth’s distance from its star, making it easy to spot. But it’s still more than 10,000 times fainter than its host star—the equivalent of trying to spot a firefly near a large lighthouse from more than 50 miles away.

The most recent observations place the planet’s atmospheric temperature at about 1300C (2370F) and indicate that its atmosphere contains clouds of reddish silicate dust. “It would be a terrible place to live,” Hinkley said. “If you could float in the atmosphere, you’d be roasted alive.”

Astronomers have previously obtained direct images of about 20 exoplanets, including HIP 65426 b, using ground-based telescopes. But this meant dealing with noise from Earth’s atmosphere and limiting observations to a narrow range of visible wavelengths. By contrast, the latest images from the cold, airless environment of space cover a wide range of wavelengths, including infrared, which makes up most of the light produced in the planet’s atmosphere.

“The best wavelength to observe a planet is the one at which it produces its innermost light, as this is directly related to the temperature of the planet,” said Dr Beth Biller, principal investigator and astronomer at the University of Edinburgh. .

HIP 65426 b is only 10-20 million years old, much younger than the 4.5-billion-year-old Earth, and recent observations provide new insights into what Jupiter and Saturn looked like in their infancy.

Dr Vivien Parmentier, associate professor of physics at Oxford University, who was not involved in the latest work, said: “Opening a new window on the universe always brings surprises. Planets form large and shrink over time, and this baby planet shrank faster than we expected. It gives us amazing insights into how planets formed and how our own solar system formed.”

In the future, James Webb is expected to make detailed observations of more distant Earth-like planets, including potential planets. living conditions.

The results are published in a preprint published on the website Archive site.

About the author


Leave a Comment