China just successfully landed its first rover (探测器) on Mars, becoming only the second nation to do so. Tianwen-1 arrived in Mars’ orbit (轨道) in February 2021 after being sent into space on a Long March 5 rocket in July 2020.

After circling the Red Planet for three months, the Tianwen-1 lander, with the rover attached, separated from the orbiter to begin its going down toward the planet’s surface. Once the lander and rover entered Mars’ atmosphere, the spacecraft went through the “seven minutes of terror” before attempting soft landings on Mars. A heat cover protected the spacecraft during the landing. After that the spacecraft safely parachuted (用降落伞投放) down to the Utopia Planitia region, a plain in the planet’s northern part. Tianwen-1’s landing platform fired some small, downward-facing rocket engines to slow down during the last few seconds of its landing.

China’s Mars rover, called Zhurong, is expected to spend at least 90 Mars days roving around on Mars to study the planet’s composition and look for signs of water ice.

Zhurong will study the Red Planet, and the orbiter will serve as a data station for communications between Zhurong and mission controllers on Earth. The orbiter is designed to last for at least one Mars year, or about 687 Earth days.

China is also planning a Mars mission in 2028, much like a joint NASA and ESA mission scheduled to begin that same year. China is also working with Russia on another mission scheduled to start in 2024.

NASA has made history today, conducting the very first powered flight on another planet. The Mars Helicopter Ingenuity (机智号) successfully took to the Red Planet skies for a brief journey, which will hopefully be the first of several.

Along with accumulating 30 minutes and 48 seconds of flight time, the helicopter has traveled over the surface a distance of 2.2 miles, flying as high as 12 meters and as fast as 5 meters per second.

Flying a craft for a few seconds might not sound like too big an accomplishment, but it’s quite a remarkable achievement of engineering. Ingenuity is flying in conditions unlike any possible on Earth - the gravity on Mars is only one-third as strong as Earth’s, and the atmosphere is extremely thin, at just one percent the density compared to the Earth. Combined with the extreme cold and a lengthy radio delay, the mission has got a lot that can go wrong.

And it already has. After surviving its first cold night on Mars, Ingenuity was set to take off on April 11, but a software error during a high-speed spin test of its rotors (螺旋桨) on April 9 threw a spanner in the works. After troubleshooting the issue, NASA developed a fix and beamed a software update to the Red Planet. If all goes to plan, NASA will conduct a few more flights over the next few weeks, sending Ingenuity higher and farther each time.

“Now, 117 years after the Wright brothers succeeded in making the first flight on our planet, NASA’s Ingenuity helicopter has left this amazing footprint of success on another world,” says Thomas Zurbuchen, NASA Associate Administrator for Science. “While these two symbolic moments in NASA history may be separated by time and 173 million miles of space, they now will forever be linked. To show respect for the two bicycle makers from Dayton, this first of many airfields on other worlds will now be known as Wright Brothers Field, in recognition of the ingenuity and creativity that continue to encourage exploration.”

Trash-Eating Robots

It has become common knowledge that our oceans are filled with garbage. Broken objects, used plastic bottles and so on fill our beaches and cover the ocean floor, doing immense damage to ocean creatures. Many individuals and organizations are working to remove this garbage and recent technological developments have given them a new tool to do so: trash-eating robots.

Robots of various shapes have been designed to collect garbage that they find floating in the ocean. For example, the French company IADYS has developed what it calls the jellyfishbot. 【小题1】 The jellyfishbot is remotely controlled and can clean up to 1,000 square meters per hour. It contains a net that can hold up to 30 liters. The jellyfishbots’ small size and ability to be easily controlled make them ideal for cleaning up crowded areas such as ports.

【小题2】 Designed for use on rivers, the Interceptor looks like a boat with a conveyor belt that picks up trash. A shallow barrier attached to the Interceptor guides floating trash to the conveyor belt, but fish can swim under it safely. Once a sensor indicates that the dustbins are full, the Interceptor automatically sends a text message to onshore operators. These operators collect and empty the dustbins, sending the garbage to local waste management facilities.

Most of the garbage in the oceans comes down rivers. 【小题3】 Hence the Interceptor is used to stop pollution before it enters the ocean.

The Interceptor is completely solar-powered and operates on its own, which minimizes the need for human involvement. Robots are able to clean up large amounts of garbage without humans struggling with beach cleanup by hand. 【小题4】