New Planet and Pluto Stamps Available Today!

They’re here and they’re from outer space! The U.S. Postal Service has two new sets of Forever® stamps based on NASA’s exploration of the Solar System: the Views of Our Planets and Pluto—Explored! series, both of which become available for purchase on May 31, 2016. Designed by Antonio Alcalá, the Views of Our Planets stamps feature…

Hail Hydra: Pluto’s Moon is Covered in Almost Pure Water Ice

Discovered in June 2005, distant Pluto’s outermost moon Hydra it thought to have formed during the same collision four billion years ago that created the Pluto-Charon system that we see today. Yet despite its age this 31-mile (50-km) -long moon appears remarkably clean and bright,  as witnessed by New Horizons during its close pass through the Pluto system in July 2015.

Pluto’s Frozen Lake Hints at a Warmer Past

Hockey fans take note: future visitors to Pluto may want to bring along their sticks and skates—the distant planet may harbor some pristine ice in the form of frozen ponds and lakes! (NASA might have to work on a lightweight, collapsible Zamboni first though.)

Surprise! Pluto May have Clouds

We could be calling it Cloudgate—”leaked” information from internal emails identifying structures in Pluto’s already hazy atmosphere that could very well be clouds, based on a March 4 article in New Scientist. The image above shows sections of a New Horizons image attached to an email sent by SwRI scientist John Spencer, in which he noted particularly…

Why Are Pluto’s Moons So Weird?

Whether you call it a planet, a dwarf planet, or a Kuiper Belt or Trans-Neptunian Object—or all of the above—there’s no denying that Pluto and its family of moons are true curiosities in the Solar System. Not only does little Pluto have one moon, Charon, that’s so massive in comparison that they both orbit each other…

There’s More Water Ice on Pluto Than First Thought

When New Horizons made its close pass pf Pluto on July 14, 2015, it did much more than just take pretty pictures; it was also scanning the planet with a suite of science instruments designed to determine the nature of its surface, atmosphere, composition, and other key characteristics. One of these instruments was the Linear Etalon Imaging…

The Old Charon in the New Charon’s Arms

An image like this could only be captured by an observer who’d traveled the 3.2 billion miles to take it beyond the orbit of Pluto! Luckily for us, in July 2015 we had exactly that: the New Horizons spacecraft, which had spent the previous nine and a half years soaring across the Solar System.

This Giant Ice Volcano on Pluto is All Wright

This bumpy wrinkled pucker is actually an enormous ice volcano — i.e., a cryovolcano — on the surface of Pluto, imaged by the passing New Horizons spacecraft on July 14, 2015. Informally called Wright Mons, the feature is about 90 miles (150 km) across and 2.5 miles (4 km) high, about as high as some of the tallest…

Planetkiller Presents New Evidence for “Planet X”

A planet-killing astronomer is now attempting to introduce a new world into the Solar System. Self-professed “Pluto killer” Mike Brown — the Caltech professor and astronomer whose discovery of Eris in 2005 prompted the reclassification of what constitutes a full-fledged planet, thus knocking Pluto from the list a year later — is now offering up evidence for the existence of a “real” ninth…