Atmosphere

Watery exoplanet’s skies suggest unexpected origin story

HAT-P-26b illsutration
WET AND WILD The exoplanet HAT-P-26b, illustrated here, has relatively low levels of heavy elements in its atmosphere, compared with those found in Neptune’s atmosphere. As a result, the exoplanet may have had a different origin story than ice giants in our solar system.

A watery world about 430 light-years from Earth may have had a relatively calm origin.

The Neptune-mass exoplanet, HAT-P-26b, has surprisingly low levels of heavy elements in its atmosphere, suggesting that it formed close to its star, researchers report in the May 12 Science. That’s different from how the ice giants in Earth’s solar system, Neptune and Uranus, formed, suggesting possible new insights into different ways planetary systems originate throughout the galaxy.

“With the observations of exoplanets’ atmospheres, we are looking outward to look in,” says study coauthor Hannah Wakeford, an astronomer at NASA’s Goddard Space Flight Center in Greenbelt, Md.

Scientists mostly use computer simulations to try to understand how planetary systems form. These simulations are based, in part, on how the planets in Earth’s solar system coalesced, but it’s unclear how common these types of planetary origins are. Many Neptune-sized worlds, for instance, have orbits vastly different than the ice giants of Earth’s system. But if the abundances of heavy elements in atmospheres of exoplanets in other systems resemble the abundances for planets of similar mass…

New Super-Earth May Be Best Yet for Finding Signs of Life

It was only a couple of weeks ago that astronomy fans were all excited about planet GJ 1132b, which shows evidence of an atmosphere. But the information from outside our solar system comes thick and fast (scientists have catalogued over 3,400 exoplanets), and now we have planet LHS 1140b to get excited about. Why? This planet, 40 light years away in the constellation Cetus, might have the conditions necessary for life. Specifically, it is a rocky planet with an orbit around its sun that…

Jupiter’s Great Red Spot has company. Meet the Great Cold Spot

Jupiter's cold spot
SPOTTED Jupiter’s northern aurora, shown in this Hubble Space Telescope image, may help generate the newly detected “Great Cold Spot” in the planet’s atmosphere.

Jupiter’s got a second giant spot.

Called the Great Cold Spot, this dark mark is twice as big as Earth, but cooler and more fickle than the planet’s famous (and similarly sized) Great Red Spot. The cool spot sits in Jupiter’s northern regions, not far from the stunning northern aurora in the planet’s atmosphere. The aurora may play a role in creating the newly detected dark mark, researchers report online April 10 in Geophysical Research Letters.

“We can’t be exactly sure how the spot forms,” says study coauthor Tom Stallard, a planetary scientist at the University of Leicester in England. “But we are sure it is there because we observed it numerous times.”

Stallard and colleagues got their first clue that the Great Cold Spot existed when they used the Very Large Telescope in Chile to study an ion of hydrogen in Jupiter’s atmosphere. While…

Jupiter’s Great Red Spot has company. Meet the Great Cold Spot

Jupiter's cold spot
SPOTTED Jupiter’s northern aurora, shown in this Hubble Space Telescope image, may help generate the newly detected “Great Cold Spot” in the planet’s atmosphere.

Jupiter’s got a second giant spot.

Called the Great Cold Spot, this dark mark is twice as big as Earth, but cooler and more fickle than the planet’s famous (and similarly sized) Great Red Spot. The cool spot sits in Jupiter’s northern regions, not far from the stunning northern aurora in the planet’s atmosphere. The aurora may play a role in creating the newly detected dark mark, researchers report online April 10 in Geophysical Research Letters.

“We can’t be exactly sure how the spot forms,” says study coauthor Tom Stallard, a planetary scientist at the University of Leicester in England. “But we are sure it is there because we observed it numerous times.”

Stallard and colleagues got their first clue that the Great Cold Spot existed when they used the Very Large Telescope in Chile to study an ion of hydrogen in Jupiter’s atmosphere. While…

Extreme gas loss dried out Mars, MAVEN data suggest

MAVEN probe
Solar wind has expelled two-thirds of the Martian atmosphere’s argon and a majority of its carbon dioxide into space, data from the MAVEN probe (illustrated here) suggest.

LOST IN SPACE

The Martian atmosphere definitely had more gas in the past.

Data from NASA’s MAVEN spacecraft indicate that the Red Planet has lost most of the gas that ever existed in its atmosphere. The results, published in the March 31 Science, are the first to quantify how much gas has been lost with time and offer clues to how Mars went from a warm, wet place to a cold, dry one.

Mars is constantly bombarded by charged particles streaming from the sun. Without a protective magnetic field to…

Blue Haze of Pluto

Image: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Smog getting you down? Consider this: even Pluto has got that!

Scientists stitched together images from the Long Range Reconnaissance Imager (LORRI) from NASA’s New Horizons spacecraft when it was about 120,000 miles (200,000 kilometers) away from Pluto. The resulting image of Pluto’s receding crescent shows a spectacular blue “haze” in the dwarf planet’s atmosphere:

Scientists believe the haze…