Articles

Emily Lakdawalla

It had never occurred to me to think about geostationary satellites in Mars orbit before reading a new paper by Juan Silva and Pilar Romero. The paper shows that it takes a lot more work to maintain a stationary orbit at an arbitrary longitude at Mars than it does at Earth.

Jim Bell

I'm absolutely floored when I stop to think that our beautiful blue ocean is only one of perhaps a half dozen or more oceans on other worlds in our solar system, and only one of probably millions (or more) oceans on other Earth-like planets in our galaxy. Oceans abound!

Bill Dunford

Mars and Earth share a truly striking family resemblance, but there's no mistaking which one is home.

Bill Dunford

Some lovely, rarely-seen images from the MESSENGER mission.

Emily Lakdawalla

A reader comment inspired me to dig up an oldie but a goodie: a sequence of photos of the Moon transiting Earth, seen from a very long way away,

Emily Lakdawalla

While researching another story, I came across an image I don't remember ever seeing before, of a moonrise from an unexpected source.

Bill Dunford

Why spend effort and scarce resources on space exploration when we have so many problems here at home? Turns out, there are some pretty good reasons.

Emily Lakdawalla

With the Landsat Data Continuity Mission scheduled to launch on Monday, there's been a lot of Tweeting about Landsat, and through one such Tweet I learned about a resource that I hadn't known existed before: the LandsatLook Viewer. This is a graphical interface to more than a decade worth of Landsat data, a tremendous resource for anyone interested in Earth's changing surface, natural or manmade.

Emily Lakdawalla

It's taken me a year to face the emotionally draining task of reading and writing about Galileo's cruise phase as chronicled in the mission's newsletters.

Björn Jónsson

This is a very large (19000 pixels square) mosaic of the fjords and glaciers of southern Greenland. I had been interested for a long time in experimenting with the processing of Earth satellite imagery just to get a comparison to the other planets.

Emily Lakdawalla

Today hurricane Sandy is a major threat to life and property across the west coast of the northern Atlantic ocean. I just want to give thanks in advance to all the people who have devoted their careers to making sure that Americans have sufficient warning of devastating, unstoppable weather events like this one.

Emily Lakdawalla

As astronaut Don Pettit prepared for his return to Earth, he tweeted several beautiful shots from the Space Station.

Mat Kaplan

Talk about changing climates on this world and others brought 600 people to the Boulder Theater.

Emily Lakdawalla

A solar eclipse isn't just a spiffy sight to Earthlings; it looks pretty cool to lunar dwellers as well.

Bruce Betts

Evidence continues to pile up that the Rio Vichada structure in Colombia is indeed the largest impact structure in South America.

Jason Davis

Last week, India launched RISAT 1, a new Earth-observing satellite. How does its synthetic aperture radar compare to that of Envisat, which has fallen silent?

Neil Patrick Stewart

The International Dark Sky Association designated Big Bend as an International Dark Sky Park, confirming its status as an incredible place to stargaze.

Pat Donohue

This is the first in a series of posts based on field notes and memories supplemented by background reading material from the Meteor Crater Field Camp that was held from October 17-23, 2010.

Emily Lakdawalla

I ran into a semantic problem today: what to call the science of studying liquids on Titan?

Emily Lakdawalla

Evaporites form on planetary surfaces when dissolved chemical solids precipitate out of saturated solution as their liquid solvent evaporates and, until recently, were known to exist only on Earth and Mars. This article from the IAG Planetary Geomorphology Working Group describes the third planetary instance of evaporite, discovered on Saturn's moon Titan.