Welcome to the Red Planet

Categories: Feature Stories Mars

Google Mars enables you to “fly” through the martian landscape, zooming in to examine features in detail. Shown here is 3-D perspective image of Candor Mensa. The gray rectangular overlay is a high-resolution image, which is available for a portion of the scene.
Credit: ESA/DLR – NASA/JPL/University of Arizona – NASA/USGS – Google

Did you ever wish you could stroll through the caldera of Olympus Mons, the largest volcano in the solar system? Study the rock formations in Valles Marineris, a martian canyon as wide as the United States? Or retrace the tracks of NASA’s Spirit and Opportunity rovers?

Then you’ll want to check out Google Mars. Tucked away inside the recently released Google Earth 5.0, Google Mars is the impressive product of a three-year collaboration between Google and the Intelligent Robotics Group at NASA Ames Research Center.

First things first: You can download Google Earth 5.0 at earth.google.com. After you launch the program, find the icon in the toolbar at the top that looks like Saturn. Click it and select Mars from the pull-down menu. Welcome to the Red Planet!

Google Mars uses the same technology as Google Earth, but the imagery comes from various NASA and ESA orbital satellites, dating as far back as the Viking orbiters in the 1970s, and including images taken as recently as within the past year by NASA’s Mars Odyssey and Mars Reconnaissance Orbiter, and ESA’s Mars Express, all three of which are still in operation. Although captured at different resolutions and under different lighting conditions, these various images are stitched together seamlessly to provide a wonderful immersive experience. Well, almost seamlessly – you do encounter the occasional bizarre artifact.

Like Google Earth, Google Mars lets you explore Mars in 3-D. It’s like an atlas and a flight simulator combined into one. You can, of course, zoom in and out to see varying amounts of detail. But you can also shift perspective. For example, if you want to check out Valles Marineris, you can wander along the canyon rim, looking down, or shift your viewpoint to the valley floor and gaze up at the canyon walls. (A useful hint: holding down the Shift key while you drag your mouse around is the simplest way to shift perspective.)

Clicking a colored square in Google Mars pops up a window containing a thumbnail of a high-resolution image. From there you can link to a Web page containing additional information about the image, and in some cases, load the image directly into Google Mars.
Credit: NASA/JPL/MSSS – Google

Not all of the highest-resolution data loads automatically. Colored squares, each color representing images captured by a particular orbital camera, appear where more-detailed views are available. Clicking an icon pops up a window that describes the image, and offers a link to a Web page containing additional information. Some images can be loaded directly into Google Mars, overlaying the existing imagery. Note, however, that although the global map of Mars appears in full color, the highest-resolution images are black-and-white.

One of the primary motivations for developing Google Mars was to provide scientists with an easy way to access Mars images. All of the image data in Google Mars are publicly available elsewhere online. But, says Matt Hancher, one of the NASA members of the team that developed Google Mars, “the interfaces for searching for these images through the Planetary Data System, the PDS, right now are quite clunky. If you know exactly what you’re looking for, then it’s possible to find it, it’s all there, it’s public. But it’s a painful process.”

With Google Mars, Hancher says, “the scientists can go directly from browsing the planet” to finding all of the image data available for a specific location. With Google Mars, “you can see what’s available without having to search in five different indexes.”

For example, you can display the paths followed by NASA’s Mars Exploration Rovers, Spirit and Opportunity, including the rovers’ waypoints, locations where they stopped to collect scientific data. Clicking a waypoint opens a window containing Web links to the data.

But Google Mars isn’t intended to be used only by scientists. The regions over which the MER rovers have traveled also contain some of the most stunning imagery Google Mars has to offer. When you zoom in on the terrain traversed by Spirit or Opportunity, camera icons appear; clicking one of these icons lets you “fly” into a panorama captured by the rover’s PanCam, a high-resolution camera. It’s easy to lose an hour or two navigating within these panoramas, zooming in to see details as small as individual rocks and boulders, then back out to admire the scenic vista. Check out, for example, the view of Cape Verde, a rock outcrop, taken from the rim of Victoria Crater by the PanCam on Opportunity.

In addition to imagery, Google Mars includes extensive material from William K. Hartmann’s popular-science book, “A Traveler’s Guide to Mars.” Each book excerpt – they appear at various places on the planet that are of particular historic or scientific interest – is marked by a green icon of two hikers.

Google Mars can display the paths of NASA’s Mars Exploration Rovers, Spirit and Opportunity. Shown here is the path that Opportunity followed into and around Victoria Crater. Red diamonds indicate waypoints, where the rover collected science data. Camera icons indicate available panoramic images, which can be opened and explored from within the application.
Credit: ESA/DLR – NASA/JPL/University of Arizona – Google

The challenge facing Google Mars’s creators, now that the software has been released, is how to keep it up-to-date. Although a great deal of image data has already been linked in to the program, Google Earth (and by extension Google Mars) is really a browser, not a repository of data. Each included image had to undergo extensive processing to transform the raw image data sent back by a NASA or ESA spacecraft into a usable format. But new images are being sent back from Mars daily, and this most-recent imagery is not currently accessible through Google Mars.

“We’re working now to understand how to set up those processes, so the most recent publicly released imagery of Mars will always be available,” says Hancher. “That’s what going to make a useful tool to scientists, and that what’s going to make it fun and interesting for the public.”

In the meantime, if you’re looking for someplace inexpensive to go on your next vacation, consider Mars. With the release of Google Earth 5.0, it’s easier than ever before to check out the best sights the Red Planet has to offer.