Jezero Crater, which once held a lake with the same volume of water as Lake Winnipeg, has been chosen as the landing site of the upcoming Mars 2020 mission. More than 60 candidate locations were scrutinized and debated before Jezero was selected. Mars 2020 launches in July 2020. When it lands on Mars in February 2021, a rover will hunt for signs of past bacterial life and collect and store rock and soil samples to be retrieved and returned to Earth on a future mission.
“The landing site in Jezero Crater offers geologically rich terrain, with landforms reaching as far back as 3.6 billion years old, that could potentially answer important questions in planetary evolution and astrobiology,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate. “Getting samples from this unique area will revolutionize how we think about Mars and its ability to harbor life.”
Jezero Crater is 28 miles wide (45 km) and once home to an ancient river delta that may have preserved organic molecules and potential signs of microbial life. From orbit, satellites have identified at least five different kinds of rock in the crater including clays and carbonates, minerals that form in presence of water. This diversity of landforms also makes it challenging for the team to land the rover. Along with the usual small impact craters there are lots of boulders, cliffs and depressions filled with sand deposited by Martian winds.
NASA’s got its hands full. Well before Mars 2020 arrives, the Mars InSight lander is scheduled to touch down on the Red Planet at about 2 p.m. (Central Time) Monday, Nov. 26. You can tune in to watch coverage of the live event on NASA Live.
InSight is an acronym for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport. Unlike other missions to explore and map the Martian surface or atmosphere, the InSight lander will study the planet’s interior using a seismometer to detect marsquakes and a temperature / heat probe that will penetrate 16 feet (5 meters) into the ground to measure the planet’s interior temperature.
A third experiment uses radio waves sent from Earth to the lander to determine its exact location. Mars orbits the sun in just under two years. During that time, the sun pushes and pulls on the planet, causing it to wobble slightly. It also changes the frequency of the radio signal reflected back to Earth from the lander. Measuring those changes yields not only the size of Mars’ iron-rich core but will help to determine whether it’s liquid, and what other elements, besides iron, may be present.
By getting right to the core of things (so to speak), scientists hope to learn more about how Mars formed but also other rocky planets like the Earth, Venus, Mercury and even the moon. We might also come to better understand why Mars lost its planetary-wide magnetic field, the planet’s main defense against having its atmosphere stripped away. Mars is in part so cold and desert-like today because of its skimpy atmosphere, about 100 times thinner than Earth’s.
If all this talk of landing on Mars has got you excited to see the planet, it’s beautifully placed for viewing any clear evening this month. It now shines just a tad brighter than Vega in the Summer Triangle and stands 35° (three and a half fists) high due south around 6:30 p.m. local time. I observed the planet two nights ago up in Grand Marais, Minn. at a teaching event. It’s certainly shrunk since mid-summer, when it was closest to Earth and big and bright. But I could still clearly make out its gibbous phase, dusky dark surface markings and even a nubbin of a polar cap.