Mars Rover Tackles Steep Hill, Spins Wheels, Gives Up
Opportunity may be the Mars roving champion, but even champions have their limits.
Roving across an alien landscape isn't easy, but NASA's Mars rover Opportunity has proven time and time again that it is the reigning champion of Mars off-roading. Alas, all champions have their limits and it looks like the veteran robot has met its match.
While exploring the slopes of "Marathon Valley" on the western edge of 14 mile-wide Endeavour Crater in Meridiani Planum, rover drivers at NASA's Jet Propulsion Laboratory in Pasadena, Calif., made the bold decision to command Opportunity to climb the most extreme slope it has encountered in its 12 years of exploring Mars.
In an attempt to reach a target near the crest of "Knudsen Ridge," the 6-wheeled rover had to surpass a 32 degree slope on March 10. Anticipating some slippage, the rover's route planners added many more wheel rotations to cover the distance. To climb a hill, Opportunity wasn't afraid to do what it takes to scramble up the slope.
On the third attempt, after the planned wheel rotations were completed, the tenacious rover only managed to edge 9 centimeters (3.5 inches) up the hill. The commanded wheel rotations would have driven Opportunity 20 meters (66 feet) on a flat surface without slippage, so it was clear that Opportunity had spun its aluminum wheels into the dusty surface and the JPL team decided that this was one hill too far and planned an alternate route to a new target further west.
Since then, Opportunity has carried out 8 drives, including a reverse maneuver back down the hill for 8.2 meters (27 feet) and then back uphill for 60 meters (200 feet) toward its new objective.
Interestingly, Opportunity turned the Marathon Valley retreat into a chance to clear some dust off its solar panels. "Shake it off! Opportunity attempts steepest climb. Drive tilt/vibration dusts solar array," the rover's official Twitter account tweeted on Thursday with a photo showing streams of dust slide off its top deck:
Opportunity took this latest challenge in its stride, and that insurmountable slope is a distant memory and the change in plan shouldn't impact its mission objectives. Both the intended and alternate targets hold interesting clues to Mars' wet past. Guided by its satellite buddy, NASA's Mars Reconnaissance Orbiter, Opportunity has been zeroing in on clay deposits detected from orbit, basically minerals that could only have been formed by the sustained presence of surface water on ancient Mars.
While the rover may be showing signs of old age, it's certainly proving that it's no slouch, showing us all that it will at least attempt any challenge Mars throws at it.
A shadow and tracks of NASA's Mars rover Opportunity appear in this March 22, 2016, image, which has been rotated 13.5 degrees to adjust for the tilt of the rover.
'Selfies' are all the rage these days. Every smartphone is attached with a camera and to the Internet, so it was inevitable that our vain species would take full advantage of the technology, snapping endless photos of cats and, of course, ourselves. Selfies -- or 'self portraits' to the uninitiated -- have become such a cultural phenomenon that Oxford University Press has declared 'Selfies' their word of the year. This may sound asinine, but Merriam-Webster Dictionary balanced it out
. In the spirit of fairness, I've combined the two words of the year and applied them to robots. Yes, robots. Robots that explore space, doing science. And just in case you didn't know, robots can be pretty vain too, taking snapshots of their junk for the whole Internet to see. To narrow the field down a bit, I've only selected robots that have photographed parts of their own structure, or attached components. I've also allowed the occasional robotic camera that was deployed for the sole purpose of taking a selfie
(nice effort, IKAROS).
The first robot that likely comes to mind is the undisputed
King of Selfies
, NASA's Mars Science Laboratory rover Curiosity. The car-sized rover impressed the world with its selfie prowess when mission scientists released a stunning high-resolution mosaic of the rover in November 2012, only a couple of months after it landed inside Gale Crater. Curiosity achieved the feat by holding its Mars Hand Lens Imager (MAHLI) at (robotic) arm's length, taking a truly authentic "selfie." The world applauded this effort.
But Curiosity certainly wasn't the first robot on Mars to snap its own picture, and it won't be the last. Although the Viking landers that touched down on the Red Planet in 1976 didn't have robotic arm-mounted cameras capable of taking a "true" selfie, they did their best.
from Viking 2 was snapped on Nov. 2, 1976, showing a part of the lander's deck, the American flag, the bottom of the robot's high-gain antenna and a boulder-littered Utopia Planitia, the largest identified impact crater on Mars.
Staying on Mars, some amazing panoramic shots and top-down self portraits have been attained by NASA's epic twin Mars Exploration Rovers Spirit and Opportunity. As you've probably guessed, commanding a robot on another planet to take self portraits isn't for fun (even though the outcome
a lot of fun), it actually serves a purpose. In the case of Viking and Curiosity, engineers on Earth can study the photos to see the condition of instruments on the robots' 'decks.'
, for solar powered rover Spirit, using its mast-mounted panoramic camera was very useful for capturing amazing 360 degree views of the surrounding terrain. It was also great for keeping track of the build-up of Martian dust on its panels. In this photo taken in 2005, Spirit's solar array shines in the sun, having collected only a very thin layer of dust two years after it landed.
Spirit's twin rover Opportunity soldiers on to this day, exploring the Martian surface after nearly a decade since landing. Jan. 25, 2014, is its 10 year Mars "birthday" (mark your calendars!). Currently exploring the edge of Endeavour Crater, helping to piece together clues of Mars' evolution (complementing the science being done by Curiosity), Opportunity is no stranger to taking its own photo. As Spirit and Opportunity were designed to the same specifications, Opportunity can also take 360 degree views and monitor dust build-up on its solar panels.
in 2011, its once shiny solar array is blanketed with a camouflaging coat of dust.
No, robotic Mars explorers aren't especially fond of sefies, it's just that NASA has sent a lot of Mars surface missions in the past few years. Seen here in 2008, NASA's Mars arctic lander Phoenix took its own photo using a mast-mounted panoramic camera in a similar style to Spirit and Opportunity. It seems that the first rule of robotic selfies is: If it ain't broke, don't fix it.
Now for something a little different. In 2007, the European comet-chasing spacecraft Rosetta made close approach with Mars, coming within 1,000 miles of the surface, using the planet for a fuel-saving gravity assist. The boost in speed is allowing Rosetta to catch up with comet 67P/Churyumov–Gerasimenko -- an encounter that is planned for 2014. But during the flyby, the spacecraft managed to snap this iconic photo of Mars from space. What makes
so special is that Rosetta also caught its own solar array in the shot.
Leaving Mars, we now head to Venus where, in 1982, the Soviet Venera 13 lander managed to survive the hellish conditions and transmit data for two hours. In that time it also returned some color photos of the Venusian surface. In those photos, the hardy lander was able to capture some of its jagged landing gear at the bottom of the shot. It may not be perfect, but while sitting in a pressure-cooker with a limited amount of time to return valuable data, it's a superb effort.
In a video released by the Chinese Space Agency of the Chang'e 2 lunar orbiter in 2010, the view shortly after launch was captured by a camera overseeing the deployment of the mission's solar panels.
, the video in its entirety
Whoa! What's that huge UFO that photobombs the shot?
Oh, that's Earth.
The Japanese Hayabusa asteroid sample return mission got a little creative with this selfie effort. In 2005, as it approached near-Earth asteroid Itokawa, with the sun at its back the mission snapped its shadow falling on the sunlit asteroid surface.
for leading me to Hayabusa!
In 2010, the Japanese space agency JAXA launched a pioneering mission. Using only the sun's energy for propulsion, the Interplanetary Kite-craft Accelerated by Radiation Of the Sun, or IKAROS, probe set sail through interplanetary space for a January 2011 rendezvous with the planet Venus. After the solar sail was launched, two miniature wireless cameras were ejected by IKAROS as it deployed in Earth orbit,
. Then, as IKAROS reached its destination eight months later, it took a snapshot of a crescent Venus (inset). (Thank you
for reminding me about these stunning IKAROS photos!)
Special thanks to all my Twitter buddies who engaged in Wednesday evening's conversation about robot selfies!
Can you think of more space mission "selfies"? Feel free to share them in the comments below.