NOVA: Looking for Life on Mars
(DVD / NR / 2021 / PBS)
Overview: Follow along as NASA launches the Mars 2020 Mission, perhaps the most ambitious hunt ever for signs of life on Mars.
For the first time, in February 2021, a rover will attempt a risky landing in Jezero Crater, the coveted site of an ancient river delta that could possibly be a cradle of life.
DVD Verdict: If the rover, called Perseverance, finds signs of life from when Mars was a watery planet like Earth, it could mean life is more likely to exist elsewhere in the solar system - and beyond.
But getting to Jezero is not easy, as the crater boulders and cliffs make it a dangerous place to land. The spacecraft will reach Mars atmosphere traveling at over 12,000 miles per hour and will have just a few minutes to execute an elaborate descent maneuver and lower the car-sized rover to the surface in just the right spot.
If successful, Perseverance will comb the area and collect samples for possible return to Earth. Traveling onboard Perseverance is a four-pound helicopter that will conduct a series of test flights - the first on another planet.
During its journey, Perseverance will also test technology designed to produce oxygen from the Martian atmosphere, in hopes that the gas could be used for fuel - or for humans to breathe - on future missions.
The search for life on Mars has become more urgent thanks in part to probes by the two rovers now roaming Mars - surface and another spaceship that is orbiting the planet.
In recent months, they have made a series of astonishing discoveries that, once again, tempt scientists to believe that Mars harbors life - or did so in the past.
At a February conference in the Netherlands, an audience of Mars experts was surveyed about Martian life. Some 75 percent of the scientists said they thought life once existed there, and of them, 25 percent think that Mars harbors life today.
A quick start to life on Earth could mean that life could also emerge quickly on other worlds - either Earth-like planets circling other stars, or perhaps even other planets or moons in our own solar system. Of these, Mars has long looked the most promising.
Finding signs of life on Mars is by no means the only goal. If you find a habitable environment and do not find it inhabited, then that tells you something, says Steele.
If there is no life, then why is there no life? The answer leads to more questions. The first would be what makes life-abounding Earth so special.
In the end, the effort being poured into detecting primitive life on Mars may prove its greatest worth right here at home. This is a Widescreen Presentation (1.78:1) enhanced for 16x9 TVs.