Articles

Emily Lakdawalla

I wrote the following blog entry about an image from Japan's Daichi Earth-observing orbiter last week as one to keep in my back pocket for a day when I was too busy to write, not anticipating that there'd soon be a more pressing reason to write about Daichi. On April 21, after just over five years of orbital operations, Daichi unexpectedly fell silent, and is probably lost forever.

Bill Nye

The Earth is important, and sometimes we need a reminder as to just how fragile it is.

Emily Lakdawalla

Pluto's atmosphere has been a subject of fascination for planetary astronomers since -- well, since astronomers first discovered that it had an atmosphere in the early '90s. The interest is partly because it's fascinating that such a distant and cold world is capable of supporting an atmosphere, and partly because the presence of the atmosphere confounds all attempts to measure Pluto's size precisely.

Emily Lakdawalla

A while ago I posted all 99 issues of the Voyager Mission Status Bulletins in PDF format, and now I have another cool item to add to that collection: NASA EP-191,

Emily Lakdawalla

NASA announced last week the start of a Participating Scientist program for Cassini, which is big news, for outer planets scientists anyway. Lots and lots of other missions have participating scientist programs, from big missions like Mars Science Laboratory to little ones like Dawn; but this is the first time for Cassini, which is kind of surprising given that it's been almost seven years since it arrived at Saturn.

Emily Lakdawalla

Some recent photos that Cassini took from a position nearly in Saturn's shadow caught my eye, and I made a quick color composite. What an amazing view this would be if you were riding on the spacecraft!

Emily Lakdawalla

When Mariner 10 flew past Mercury, it caught an immense impact basin lying half in and half out of sunlight, which they named Caloris. Even with only half the basin visible, scientists knew it was one of the largest in the solar system. Geologists had to wait more than 25 years to see the rest of Caloris, and when they did it turned out to be even bigger than they had thought. But the fact that Caloris was only half in sunlight was fortuitous in one sense, because it meant that the spot on Mercury that was exactly opposite the area of the Caloris impact was also partially in sunlight. That spot looks weird.

Emily Lakdawalla

Here's a very pretty picture to start off the week: a really gorgeous fresh crater on the lunar farside. There's nothing particularly unusual about this crater; it's just recent and fresh so there's a mesmerizing amount of detail in the feathery patterns of the ejecta that fans outward from it.

Emily Lakdawalla

Australia's Space Policy Unit is conducting a survey of people in the commercial space industry, state and local governments, and education and research sectors as part of an effort to assess the economic value of civil space to the country.

Emily Lakdawalla

Since the Galileo mission discovered tiny Dactyl circling Ida in 1993, quite a lot of asteroid systems have been found to be binary; there are even a few triples. So it's quite reasonable to guess that two of the biggest asteroids, Ceres and Vesta, might also have satellites.

Emily Lakdawalla

We're going to celebrate Lou Friedman's 30 years of service to the Planetary Society by mercilessly making fun of him at a gala

Emily Lakdawalla

Might there be many Titan-like planets and moons, with atmospheres and liquid methane rain, rivers, and lakes, across the galaxy? It's an important question if you think that liquid methane environments could support alien life, because it turns out that Titan-like planets might be more common than Earth-like planets.

Emily Lakdawalla

I've got some lovely pictures from Saturn to show you! Every three months, the Cassini mission dumps gigabytes worth of precious Saturn data into the Planetary Data System, and the latest gift came on April 1. This particular pile of data, which was taken between April 1 and June 30, 2010, contains a lot of really terrific moon observations.

Emily Lakdawalla

Space exploration is an international endeavor and I usually try to speak as a citizen of Earth rather than one of my nation, state, or city, but I'm going to ask you to indulge me in a little local boosterism today.

Emily Lakdawalla

On April 12, 1961, Yuri Gagarin became the first human to see firsthand the blackness of space above our home planet's thin atmosphere. Since there's lots of thoughtful reporting and commentary being posted on this anniversary, I thought it'd be more useful to link to some particularly interesting posts than to add in my comments.

Emily Lakdawalla

In a paper recently published in the Journal of Geophysical Research, Georgiana Kramer and several coauthors performed a careful comparison of two data sets that seem like they're measuring the same things, so you'd think that the measurements they took would match between the two instruments. But they don't quite match.

Emily Lakdawalla

The photo I took of Curiosity's

Emily Lakdawalla

Spaceflight Now is following along as the next Jupiter orbiter, Juno, is journeying from its birthplace at Lockheed Martin in Denver to Cape Canaveral. As of this moment it has been packed up and loaded onto a flatbed trailer, which is driving through Denver with police escort, en route to the Denver airport, where it'll board a C-17 for the trip to Florida.

Emily Lakdawalla

Regular readers of this blog will find the content of today's 365 Days of Astronomy Podcast familiar, because it's an update on what the solar system exploration spacecraft are up to, based on my monthly

Marc Rayman

Three and a half years after launch, Dawn continues its travels around the Sun, maneuvering to take the same orbital path as Vesta. The spacecraft has spent most of the past month gently thrusting with its ion propulsion system. Some of the thrusting this month, however, was not designed to propel Dawn to Vesta.