National Geographic News
John Grotzinger points at a model of the Curiosity rover.

John Grotzinger, Curiosity's chief scientist, with a model of the Curiosity rover.

Photograph courtesy Paul E. Alers, NASA

Ker Than in Pasadena, California

for National Geographic

Published August 6, 2013

One year ago today, a one-ton, SUV-sized rover named Curiosity touched down on Mars after a daring landing maneuver that involved deploying a parachute at supersonic speeds and using a rocket-powered "sky crane" for the final soft touchdown. (Read: "Mars Curiosity Milestones: Top 5 First-Year Discoveries.")

Viewers around the world tuned in to witness Curiosity's "seven minutes of terror" and then cheered along with NASA scientists and engineers in mission control when news finally arrived that the landing was successful.

We caught up with Curiosity's chief scientist John Grotzinger during an anniversary celebration event at NASA's Jet Propulsion Laboratory in California on Monday to ask him what the past year has been like, what still lies ahead for Curiosity's scientific mission, and how the rover is helping lay the groundwork for a manned mission to Mars. (Related: "Curiosity Finds Evidence for a Habitable Ancient Mars.")

What has been the most exciting part of the mission for you so far?

The landing and the launch—those were all thrills. There was one very special opportunity, though. The night before launch, I stumbled my way onto Kennedy [Space Center] and found my way to the base of the launch vehicle. And then I ran into a photographer who had a pass for a guest, and I wound up standing literally toe-to-toe with the rocket. That was amazing.

In our culture, it's commonplace to see a rocket launching, but when you're next to one it's awe inspiring. And when you know it's carrying the payload that you've helped to develop, that makes it extraordinary. (Watch video of the Mars rover Curiosity.)

What questions about the red planet was Curiosity designed to help answer that are still outstanding?

We have an instrument that's able to detect complex organic molecules, and we've had a couple of sniffs that suggest there might be organics [on Mars]. But we haven't been able to confirm it, so we're looking for a stronger signal.

What we're hoping is we might eventually find an environment that's not only habitable but also has the right chemistry to preserve the organics that we think should be there. And the reason we think they're there is organics are always arriving from outer space onto every planetary surface. We would think that there's some chance to preserve them [on Mars]. (Related: "Meet One of Mars Rover Curiosity's Earthbound Twins.")

In the 1970s, some tantalizing results from experiments performed by NASA's Viking lander missions suggested there might be microbes in the Martian soil that were producing carbon dioxide or methane, but those results were later dismissed. Has Curiosity been able to help settle the debate about whether the Viking landers did or did not find evidence of life?

So far we haven't seen anything. We keep making measurements, and we've seen no methane down to the parts-per-billion level.

How is the Curiosity mission informing NASA's plans for a 2020 rover mission, which is expected to include sample returns of Martian rocks to Earth?

There will be a competition to select the final landing site [for the 2020 rover], and Curiosity's results will surely feed into that by helping us as a community understand better how Mars works. (See: "Mars Gets Its Close-Up.")

You've talked before about how Curiosity is helping lay the groundwork for a manned mission to Mars by measuring radiation on the surface of the red planet. Can you elaborate?

Of course, everybody knows that radiation is not a good thing and can cause cancer. And all astronauts have what are called career limits in terms of what they're exposed to. What Curiosity does is it can actually measure directly the radiation on Mars that astronauts would receive if they were on the planet.

One of the big questions is ... how does the atmosphere interact with the radiation and cause it to be dissipated? We know it'll be dissipated by some amount but not as much as on Earth. We can make these measurements on a regular basis and just see how much radiation an astronaut would experience over that time.

That's never been done before?

Nope. This is the first time ever. We turned on an instrument on Curiosity [called RAD] ten days after we launched so we could measure the radiation dose that an astronaut would get on the flight to Mars while protected by a spacecraft.

And then once we landed, the instrument sits on the deck of the rover, so it's unshielded and you can measure directly what the impact is of the atmosphere on controlling radiation.

Follow Ker Than on Twitter.

Babu Ranganathan
Babu Ranganathan


In the Earth's past there was powerful volcanic activity which could have easily spewed dirt and rocks containing microbes into outer space which not only could have eventually reached Mars but also ended up traveling in orbit through space that we now know as meteors. A Newsweek article of September 21, 1998, p.12 mentions exactly this possibility. "We think there's about 7 million tons of earth soil sitting on Mars", says scientist and evolutionist Kenneth Nealson. "You have to consider the possibility that if we find life on Mars, it could have come from the Earth" [Weingarten, T., Newsweek, September 21, 1998, p.12].

Read my popular Internet article, ANY LIFE ON MARS CAME FROM EARTH!


Babu G. Ranganathan*
B.A. Bible/Biology


*I have given successful lectures (with question and answer period afterwards) defending special creation before evolutionist science faculty and students at various colleges and universities. I've been privileged to be recognized in the 24th edition of Marquis "Who's Who In The East" for my writings.

Christian Adam Herrera
Christian Adam Herrera

I still remember the very day, watching Curiosity land, LIVE on CNN. Curiosity has and will keep discovering interesting finds beneficial for future missions to Mars and the public perception of the Red Planet. 

Gary Proffitt
Gary Proffitt


I and for that matter the rest of the world are totally amazed and excited by the whole curiosity mission and once again Nasa is path finding for the rest of humanity, science in new areas of our solar region of space and it is a great shame that other countries and nations have not contributed enough to this most marvellous endeavour for mankind to go where no man has been before and lead us into a new age of discovery.

Gary Proffitt
Gary Proffitt

As I have said for the the longest time, the real clues and discoveries will arrive when the trench areas and there sedimentary evidence is revealed successfully which is in itself a massive operation of which I hope that the curiosity team make the correct choices at the location choice at mount Sharp Base vicinities.

I sincerely hope that the major lesson to be learned by the curiosity mission

for mankind in terms of using technology will be learned this mission time around and these logically are as follows in no particular order.

1.....Dont base mission directives and objectives on previously poor mission accomplishments, location choices and directives.

2.....Never go anywhere new in the universe and assume you know everything based on what you have learned from your own planet and always keep an open mind.

3.....don't pay too much homage to spectroscopic analysis of atmospheres, surfaces and sub-surface sampling and dis-regard the power of colour observational research by using the sort of high powered camera and microscope technology that is available on Earth at low cost and to be frank far superior to curiosities range of instruments.

4.....The current trend of wheeled rovers is not suitable for the terrains that will provide the best information and we will see this pretty soon when the rover meets the dunes and trench area that surrounds Mount sharp, as for climbing the mountain from the camera information thus far I suspect this will be impossible. 

5.....The Hirise program of surveying Mars is massively outdated and added to the poor downlink times for Mars operations more money needs to be spent on this important observational research tech before any manned operations should be considered,

Dolly Cain
Dolly Cain

I wish Nat Geo, the Science channel, and the NASA channel would provide more frequent updates.  I came up with an equation I'm still testing.


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