Science

Curiosity streams a human voice and new telephoto images from Mars

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A chapter of the layered geological history of Mars is laid bare in this postcard from NASA's Curiosity rover (Image: NASA/JPL)
Image taken by the Mast Camera (MastCam) on NASA's Curiosity rover highlights the interesting geology of Mount Sharp (Image: NASA/JPL)
This image taken by a front Hazard-Avoidance camera on NASA's Curiosity shows track marks from the rover's first Martian drives (Image: NASA/JPL)
This image taken by NASA's Curiosity rover shows track marks from a successful drive to the scour mark known as Goulburn, an area of bedrock exposed by thrusters on the rover's descent stage (Image: NASA/JPL)
This color panorama shows a 360-degree view of the landing site of NASA's Curiosity rover, including the highest part of Mount Sharp visible to the rover (Image: NASA/JPL)
This image is from a series of test images to calibrate the 34-millimeter Mast Camera on NASA's Curiosity rover (Image: NASA/JPL)
A chapter of the layered geological history of Mars is laid bare in this postcard from NASA's Curiosity rover (Image: NASA/JPL)
Image is from a test series used to characterize the 100-millimeter Mast Camera on NASA's Curiosity rover (Image: NASA/JPL)
This chart shows increases in the volume of data coming back from NASA's Mars rover Curiosity over recent sols, or Martian days (Image: NASA/JPL)
The two donut-shaped tracks make an infinity symbol, and mark the first two drives of NASA's Curiosity rover (Image: NASA/JPL)
The SAM instrument, about the size of a microwave oven, will analyze the chemical ingredients in samples of Martian atmosphere, rocks and soil (Image: NASA/JPL)
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For the very first time in human history, a human voice was streamed from the surface of another planet and traveled some 168 million miles (267 million km) into space before it was heard on Earth. The audio was a pre-recorded message from NASA administrator Charles Bolden, who sent a congratulatory message to the engineers involved in the US$2.5 billion mission to safely land the Mars Science Laboratory – better known as the Curiosity rover – on the surface of Mars.

Streaming bits from another planet

Weeks ago, Curiosity landed on the surface of Mars with an unprecedented maneuver that, despite initially raising a few eyebrows among the public over its complexity, was performed flawlessly. Since then, the engineers at NASA have been tirelessly conducting a long series of extensive testing and software updates on the rover, gearing up for a main mission that will try and answer the question of whether Mars’ environment ever was, or still is now, capable of supporting life on its surface.The 500 kilobyte audio file was streamed back to Earth as part of a communications test. This marks the first time we've heard a human voice beamed from the surface of an alien planet. It's a small step toward extending human presence to other planets, and has been sent with the hope that, in the not-too-distant future, generations that are hearing it today will be the very same who land the first humans on the surface of the Red Planet.

One of the challenges of a landed mission is to transmit data from Mars to Earth. Curiosity has very limited transmission capabilities on the direct Mars to Earth path: its antenna dish is a single foot (30.5 cm) in diameter, and with a measly power of 15W at its disposal it could only achieve data rates of around one kilobit per second without external help.

This chart shows increases in the volume of data coming back from NASA's Mars rover Curiosity over recent sols, or Martian days (Image: NASA/JPL)

Fortunately, however, the rover gets help from three Mars orbiters that act as a relay and increase the data rates considerably. On landing day, Odyssey, the Mars Reconnaissance Orbiter (MRO) and Mars Express spacecraft were all positioned optimally to relay data and make sure that the entry and descent stage proceeded without hiccups. Ever since, MRO and Mars Express have been collecting and relaying data from and to the rover, bumping data transfer rates up to about two megabits per second, while the European Mars Express is serving the role of a backup should either of NASA's incur into problems.

Odyssey and MRO are in orbit around Mars at an altitude of 185 to 250 miles (300 to 400 kilometers) and, whenever they appear over Curiosity’s horizon, they offer radio contact with the rover for ten to fifteen minutes at a time. The connection speed improves the higher the orbiter is over Curiosity’s head, and NASA’s newly developed algorithms for adaptive data rates are maximizing the amount of data that can be beamed back to Earth on any given day.

This new approach to achieve optimal data rates has been very fruitful. Taken together, MRO and Odyssey have already relayed close to one gigabyte of data since the rover’s landing. That’s almost three times more than the Spirit, Opportunity, or Phoenix missions had achieved in the same amount of time.

New telephoto images

A chapter of the layered geological history of Mars is laid bare in this postcard from NASA's Curiosity rover (Image: NASA/JPL)

The voice playback was released to the media along with new telephoto images taken by the 100-mm lens and the 34-mm wide angle lens of Curiosity's Mast Camera (Mastcam) instrument. The high resolution images of the lower slope of the nearby Mount Sharp show eroded knobs and gulches with clearly visible geological layering.

"This is an area on Mount Sharp where Curiosity will go," said Mastcam principal investigator Michael Malin, of Malin Space Science Systems in San Diego. "Those layers are our ultimate objective. The dark dune field is between us and those layers. In front of the dark sand you see redder sand, with a different composition suggested by its different color. The rocks in the foreground show diversity -- some rounded, some angular, with different histories. This is a very rich geological site to look at and eventually to drive through."

Sniffing the Martian atmosphere

The SAM instrument, about the size of a microwave oven, will analyze the chemical ingredients in samples of Martian atmosphere, rocks and soil (Image: NASA/JPL)

As part of the preliminary checks before Curiosity drives away toward Mount Sharp, NASA engineers conducted a test in which the SAM (Sample Analysis at Mars) instrument took a brief sniff of Mars’s atmosphere. SAM’s mass and tunable laser spectrometers were used to look for the major constituents of the Martian atmosphere.

Here, there was a minor hiccup: as it turns out, an excessive amount of residual Earth atmosphere and calibration gas leaked into the tunable laser spectrometer. As a result, the very first measurement registered unexpectedly high levels of methane, and caused quite a stir among NASA engineers – at least until they figured out that what they just measured wasn’t Mars’s atmosphere, but rather Florida’s. The unwanted gases have now been flushed from the system and the instruments are performing as expected.

This minor incident aside, these preliminary tests were a complete success. With all of the relevant instruments properly calibrated, Curiosity will be able to take a first, proper look at the composition of the atmosphere on Mars. Over the coming months, comparing those results to a similar analysis of local rocks that formed billions of years ago might give us a better insight into Mars’s distant past.

What’s next?

This image is from a series of test images to calibrate the 34-millimeter Mast Camera on NASA's Curiosity rover (Image: NASA/JPL)

Curiosity is currently investigating the scour marks left by the thrusters of its powered descent stage, which have uncovered bare rock. The DAN instrument, which is designed to look for subsurface water, and ChemCam are gathering information on the nature of the soil around it.

Then, in just a few days’ time, the rover will start heading east to discover new lands and landscapes on the Martian surface.

Source: NASA

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6 comments
Rt1583
This is spectacular in what way? They have been communicating back and forth via RF with the various spacecraft for decades.
Now, when it is the first manned mission that is transmitting back, that will be spectacular.
Christian Sampedro
That's just a made up milestone...
Jay Finke
I love this stuff what a interesting time we live in, I just can't get enough info . i got it bad !
Gregg Eshelman
Looks like Arizona. ;-)
Paul Perkins
When can we go?
denny245
OK, they sent a voice modulated signal back to Earth from Mars. That's great. Even though Mars has a thin atmosphere, could they turn on an external microphone to see if there are any external sounds on Mars such as the wind blowing in the background, if that is possible with an atmosphere 100 times thinner than Earths. Should be able to hear the electric motors on the Curiosity would imagine. Be interesting to hear the sound quality.