Category Astronomy/Space

The New Horizons spacecraft spied extensional faults on Pluto, a sign that the dwarf planet has undergone a global expansion possibly due to the slow freezing of a subsurface ocean. A new analysis by Brown University scientists bolsters that idea, and suggests that ocean is likely still there today. Credit: NASA/JHUAPL/SwRI

When NASA’s New Horizons spacecraft buzzed by Pluto last year, it revealed tantalizing clues that the dwarf planet might have – or had at one time – a liquid ocean sloshing around under its icy crust. According to a new analysis led by a Brown University Ph.D. student, such an ocean likely still exists today.

The study, which used a thermal evolution model for Pluto updated with data from New Horizons, found that if Pluto’s ocean had frozen into oblivion millions or bil...

Image showing the thickness of Enceladus’s ice shell, which reaches 35 kilometers in the cratered equatorial regions (shown in yellow) and less than 5 kilometers in the active south polar region (shown in blue). Credit: © LPG-CNRS-U. Nantes/U. Charles, Prague

With eruptions of ice and water vapor, and an ocean covered by an ice shell, Saturn’s moon Enceladus is one of the most fascinating in the Solar System, especially as interpretations of data provided by the Cassini spacecraft have been contradictory until now. An international team recently proposed a new model that reconciles different data sets and shows that the ice shell at Enceladus’s south pole may be only a few kilometers thick...

The youngest known hot Jupiter, detected around the star in formation V830 Tau, travels through the star’s magnetic web (white and blue lines), making it hard to detect such planets. Credit: Jean-François Donati/CNRS

For the past 20 years, exoplanets known as ‘hot Jupiters’ have puzzled astronomers. These giant planets orbit 100 times closer to their host stars than Jupiter does to the Sun, which increases their surface temperatures. But how and when in their history did they migrate so close to their star? Now, an international team of astronomers has announced the discovery of a very young hot Jupiter orbiting in the immediate vicinity of a star that is barely 2 million years old – the stellar equivalent of a week-old infant...

An illustration to explain the dynamics of the ultra-relativistic third Van Allen radiation belt, by Andy Kale. Credit: Andy Kale

Like a protective shield, the Earth’s magnetosphere absorbs and deflects plasma from the solar wind which originates from the Sun. When conditions are right, beautiful dancing auroral displays are generated. But when the solar wind is most violent, extreme space weather storms can create intense radiation in the Van Allen belts and drive electrical currents which can damage terrestrial electrical power grids. Earth could then be at risk for up to trillions of dollars of damage.

A new discovery shows for the first time how the puzzling third Van Allen radiation belt is created by a “space tsunami...