The first six months of Curiosity's journey

Evidence of ancient water and habitable environment on Mars called a "scientific bonanza" by researchers

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Panoramic view of Curiosity rover's landing site on Mars with the ultimate destination—the sedimentary slopes of Gale crater's central peak known as Mount Sharp—in the distance 10 km away. (Credit: NASA)


Since it landed on Mars on August 6, 2012, the Curiosity rover has held Planet Earth spellbound with its striking images of a distant world that looks a lot like our own. Curiosity landed in an area of Mars known as Gale Crater, a 154-km wide basin near the equator of the Red Planet created by the impact of an ancient meteor. The area was chosen as the rover's landing site because satellite images show evidence that it might once have been flooded by fast-flowing water. Mount Sharp, the crater's central 5.5 km-high mountain contains interesting layers of sedimentary deposits of minerals that could have been formed in the presence of water. These images intrigued the mission's scientists, who are on a quest to solve the mystery of whether this region was once able to support life.

In just the first seven months since landing, the roving geochemistry lab has logged nearly 800 metres on its odometer and used its array of cameras and instruments to examine a number of soil and rock targets. Scientific data has already begun to flow, shedding light on the crater's mysterious geologic and watery past.

Within days of its arrival, Curiosity began testing its cameras, robotic arm and suite of 10 instruments, including the Canadian APXS, before starting its trek towards its ultimate destination: the base of Mount Sharp. But first, mission scientists chose to conduct a short detour to a low-lying depression a few hundred meters to the northwest nicknamed "Yellowknife Bay." The team decided to drive to this region, its first science destination of the mission, because it features a different type of geologic terrain compared to the spot where Curiosity landed.

Yellowknife, Mars

To the great delight of Northern Canadians, mission scientists named several features of Curiosity's landing site in honour of the capital city of Northwest Territories and regions nearby. Yellowknife has historically been a starting point for geological expeditions to explore some of the oldest rocks in North America—up to 2.7 billion years old. Images from Mars orbiters have shown that this region of the Red Planet appears to be rich with rocks with unusual properties that may have been an ancient stream bed.

Mark Heyck, Mayor of Yellowknife, N.W.T., notes that the city was thrilled to have part of another planet named in their honour. "The naming of the Yellowknife quadrant in Gale Crater and the geologically interesting place now known as Yellowknife Bay, Mars, is a distinguished recognition that honours the history and spirit of our community, as well as the ancient geology of the Yellowknife Greenstone Belt," said Heyck.  "As new discoveries are made, we welcome the opportunity to continue this celebration of exploration, discovery and the frontier spirit – a celebration that extends from one world to another."

In December 2012, the rover reached Yellowknife Bay, a section of a larger feature dubbed Glenelg, which scientists believe is the deepest and youngest region of the crater floor.  This new area is exciting to mission geologists due to its rounded pebbles, conglomerate rocks, and a Martian surface crisscrossed by fractures filled with veins of minerals—all likely formed when water flowed through this part of the crater.

Digging into Mars

Billed as the most complex engineering task since its harrowing landing, Curiosity began conducting drill operations for the first time at Yellowknife Bay in February 2013, and bore deeper into rocks than ever before attempted on Mars.

Recovered powdered samples were tested with the onboard chemistry labs to help determine whether or not the minerals present in the bedrock were formed in the presence of water.

Early science results show that Curiosity is sitting on an ancient Martian lakebed. Clay minerals found in the rock samples indicate they could only have formed in neutral water – making the local environment once quite hospitable to life.

After wrapping up its investigations at Yellowknife Bay, Curiosity is expected to begin its six-month road trip to the base of Mount Sharp 10 kilometres away, where evidence for extensive layered deposits of clay and sulfate were identified from orbit.

APXS, Canadian Chemical Detective

Photo of APXS

Canada's hardware contribution to Curiosity's mission: the cube-shaped APXS instrument, seen here on the right side of the turret at the end of the robotic arm. (Credit: NASA/JPL-Caltech/MSSS)

Since Curiosity landed, the Canadian APXS instrument was put into action on several occasions to analyze the chemical makeup of soils and rocks at the landing site. Early results indicate that the composition of the dust in Gale crater is a good match to what had been found across the Martian globe by earlier APXS instruments aboard the twin Mars Exploration Rovers, Spirit and Opportunity. With these cross-planet comparisons using APXS data, scientists can tie together the results and findings of Curiosity with previous missions.

Whereas the APXS instrument on board Opportunity (which has been operating on Mars since 2004) needs a full night to analyze a given spot, the improved APXS on Curiosity is about 5 times faster and recently analyzed 7 spots of drill powder within one single night.

Mounted on the end of the rover's robotic arm, APXS has helped piece together the first clues of the geological history of the landing site. The instrument also helped select the first target for the rover to drill: an area in a bedrock named "John Klein" at Yellowknife Bay. Early science results show that Curiosity is sitting on an ancient Martian lakebed. Clay minerals found in the rock samples indicate they could only have formed in neutral water – making the local environment once quite hospitable to life.

APXS determined that the white veins filling the cracked bedrocks contain calcium sulfate, likely a later-stage process that happened long after the bedrock was formed. This is very similar to findings that Opportunity made at the Endeavour crater rim.

Photo Highlights: Curiosity's First 6 Months on Mars

List of photos

2012-09-07 (PDT) or 2012-09-08 (UTC) - This image shows the Canadian-built APXS on NASA's Curiosity rover, with the Martian landscape in the background. The image was taken by Curiosity's Mast Camera on the 32nd Martian day, or sol, of operations on the surface. APXS can be seen in the middle of the picture. This image let researchers know that the APXS instrument had not become caked with dust during Curiosity's dusty landing. Scientists enhanced the color in this version to show the Martian scene as it would appear under the lighting conditions we have on Earth, which helps in analyzing the terrain.. (Credit: NASA/JPL-Caltech/MSSS)

With Mount Sharp in the background, Curiosity took this self-portrait with a camera mounted at the end of its robotic arm.  (Credit: NASA)

A map of Curiosity's stop-off points as it travels from its landing site to a place called Glenelg where three types of terrain meet. The depression called Yellowknife Bay was selected as the location for Curiosity's first drilling of a sample from a target rock. (Credit: NASA)

Text description of image of Curiosity's stop-off points.

Some of the first science carried out on the mission included the use of Canada's onboard APXS instrument.  The chemical sensor has looked at the elemental composition of minerals that make up rocks and soil at various points along the rover's journey to Yellowknife Bay. For several weeks in October and November 2012, Curiosity stopped at a soil drift dubbed the Rocknest, where (as seen in the photo) the rover's wheel scuff exposed surface material which was subsequently analyzed by APXS. (Credit: NASA)

Curiosity's first drilling took place on February 8, 2013, in a rock named John Klein in Yellowknife Bay region of Gale Crater. The deeper of the two holes in this image resulted in obtaining the first powdered rock samples that helped determine the watery past of this Mars landing site. (Credit: NASA/JPL-Caltech/MSSS)