Mars first flight unlocked and 5 other top space and science stories this week

When Neil Armstrong stepped on the moon's surface in 1969, it became a defining moment for the space age. For the first time, humans truly explored beyond their home -- and it won't be the last.

We were witnesses to history once again as two robotic explorers achieved landmark firsts on planet Mars.

Don't let these moments get buried in the busyness of the week. Allow yourself to marvel. Talk to your friends and family about it. Ponder what it took to make these feats possible and what it means for the future.

Just don't let the moment slip away.

Across the universe

Seeing the black-and-white image of the chopper's shadow on the surface of the red planet, taken during the first Mars flight, was that magical moment for MiMi Aung, the Ingenuity Mars helicopter project manager.

"When I first saw it, I immediately thought of the picture Buzz Aldrin took of his boot print on the lunar surface. That iconic image from Apollo 11 said 'We walked on the Moon,'" she wrote in a statement. "Ours says 'We flew on another world.'"

Ingenuity conducted the first powered, controlled flight on Mars Monday, followed by a second riskier flight Thursday. Images and video returned by the helicopter and the Perseverance rover captured Ingenuity's historic milestones -- a true Wright brothers moment on another planet.

In between the flights, Perseverance kept busy by using its MOXIE instrument to create oxygen on the red planet, another astonishing first.

The MOXIE instrument, short for Mars Oxygen In-Situ Resource Utilization Experiment, converted carbon dioxide in the Martian atmosphere into enough oxygen to sustain an astronaut for about 10 minutes.

Ingenuity, scheduled for a third flight on Sunday, has also returned its first color image while aloft. The photo provides us all with an idea of what it looks like to fly on Mars.

While Ingenuity and MOXIE are just tech demos for now, both could contribute to humans landing on the red planet in future missions.

Defying gravity

More history was made this week when four astronauts from three countries launched from the US to the International Space Station aboard the SpaceX Crew Dragon capsule Friday. This marks the third-ever crewed flight for SpaceX and the first instance of the company making use of a previously flown rocket booster and spacecraft.

Crew-2 includes NASA astronauts Shane Kimbrough and Megan McArthur, French astronaut Thomas Pesquet of the European Space Agency, and Akihiko Hoshide from Japan.

This adds four crew members to the seven astronauts already on board the station, four of whom arrived on a different SpaceX Crew Dragon capsule in November.

It bumps the space station's total crew to 11, one of the largest groups that the orbiting laboratory has ever hosted. But the merry crowd is only temporary; Crew-1 is slated to return to Earth on April 28.

Once upon a planet

When astronauts view Earth from the International Space Station, they often remark on how beautiful it looks -- and how fragile it appears.

This view of the Anti-Atlas Mountains in Morocco was captured by ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) on NASA's Terra satellite.

Victor Glover Jr., who conducted his third spacewalk in late February, talked then about "just how special it is for there to be human life on this planet."

"It makes me want to do all that I can to protect that," the NASA astronaut said.

Earth Day, celebrated Thursday, is a good reminder for all to do our part to protect the only home we have. And some of the changes we've embraced during the pandemic over the last year actually have benefited the environment, like shopping locally, cutting down on commutes, reducing food waste and flying less.

We just need to make them common practices rather than temporary habits.

Curiosities

Calling all citizen scientists. Keep an eye out for "moon trees" -- the Royal Astronomical Society and the UK Space Agency are looking for them.

As fanciful as it may be to imagine forests filled with ghostly silver trees on the otherwise inhospitable moon, these are trees grown from 500 seeds that traveled to our lunar companion and back aboard NASA's Apollo 14 mission.

The seeds, including sycamore, redwood and Douglas fir, traveled with NASA astronaut Stuart Roosa, a former US Forest Service parachute firefighter, in his personal luggage to see how they reacted to the space environment.

Once returned to Earth, the seedlings were germinated by the Forest Service and planted around the world. There was no systematic effort to keep track of them, but NASA has since tracked down about 60 trees.

Steve Miller, vice president of the Royal Astronomical Society, thinks some of them ended up in the UK and wants to know what happened to them, hence his appeal to the public this week.

Wild kingdom

Humans and animals aren't so different from each other, after all.

After Hurricane Maria swept through Puerto Rico in 2017 with devastating impact, researchers found rhesus macaques, a monkey species living on Cayo Santiago, became more sociable with each other.

While these monkeys tend to be competitive with one another and aggressively protect their food and water, researchers discovered they actually expanded their social groups and grew more tolerant of each other post-Maria.

These interactions were measured based on grooming, which is one way monkeys bond. These grooming networks grew after the hurricane, suggesting that the monkeys were making social connections and friendships with friends of their friends -- not unlike the way humans connect and expand their social groups.

Climate changed

Lake Mead, a key reservoir on the Colorado River, could sink to its lowest levels since being filled in the 1930s, according to new projections released this week by the US Bureau of Reclamation.

Reservoirs serve as a buffer in times of scarcity, but Lake Mead -- the largest in the country -- has been impacted by climate change, overuse and drought and is only 39% full today.

If the water levels fall below 1,075 feet on January 1, 2022, significant water cutbacks could hit Arizona, Nevada and Mexico.

Talk about a stark reminder to conserve water wherever you can.

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