1 . Most solar panels acquire sunlight from only one side, meaning they can acquire more or less of it depending on where the sun is in the sky. In recent years, they’ve become far more effective typically turning around 22 percent of the light they acquire into energy. In a new study published in the journal Joule on Tuesday, scientists put forth a way to increase that percentage even higher: double-sided solar panels that can move to follow the sun.
Basically, these panels can acquire sun from not only their sun-facing side but also from the light reflected off the ground onto their dark undersides. At the same time, a GPS allows them to move on an axis from east to west in order to always be pointed at a best angle to acquire the sun’s rays. Though double-sided solar panels and sun-following solar panels are both in use currently, models that combine the two technologies aren’t widely available for commercial use, Solar experts predict explosive growth in the market soon, though.
The study authors determined that these two-sided sun-tracking panels produce an average of 35 percent more energy than immobile single-panel systems, and are 16 percent more cost-efficient. That holds true even when accounting for changes in weather conditions.
“This means that investing in double-sided and tracking systems should be a safe bet for the foreseeable future, Carlos Rodriguez-Gallegos,” the study’s lead author said.
The same warnings for solar panels and their effect on the local environment apply to the double-sided, moving systems as well, if not more so. Lead used in solar panels can be one source of local pollution, and Dustin Mulvaney, an associate professor of environmental studies, told Earther in an email double-sided panels could mean “twice as much lead” as traditional solar systems.
Since these new panels are more energy efficient, they could save not only money but also land. That would require restructuring how solar contracts currently work.
1. What does most solar panels rely on to acquire sunlight?| A．The amount of sunlight. | B．The location of the sun. |
| C．The quality of solar panels. | D．The size of solar panels. |
| A．The sun’s rays. | B．The panels’ undersides. |
| C．The double-sided panels | D．The panels’ sun-facing sides. |
| A．Uncertain. | B．Supportive. | C．Doubtful. | D．Subjective. |
| A．Double-Sided Solar Panels that Follow the Sun | B．Advantages of the Double-Sided Solar Panels |
| C．Application of the Double-Sided Solar Panels | D．New Trends of Double-Sided Solar Panels |
2 . Japanese officials say they are pleased with the quality of the asteroid (小行星) material collected by a spacecraft and returned to Earth.
Last week, officials from Japan described the samples (样品), which were collected from the Ryugu asteroid in July 2019. Ryugu sits more than 300 million kilometers from Earth. Japan’s unpiloted Hayabusa2 spacecraft removed the material after making a hole into the asteroid.
The space agency said the July 2019 mission (任务) aimed to collect samples from below the surface of Ryugu. During an earlier operation in February 2019, Hayabusa2 collected material from a different part of the asteroid. The second collection effort resulted in sample pieces as big as 1 centimeter. The black material looked similar to charcoal and was very hard. It did not break apart when picked up or poured into another container.
Earlier this month, space officials described the samples Hayabusa2 removed on its first mission as smaller, sandy pieces. They were collected from the surface of Ryugu. Hayabusa2 was launched in December 2014 and arived near Ryugu in June 2018. The Japanese space mission aims to use the samples to learn more about how our solar system formed.
To get the second set of samples in July, Hayabusa2 used an impactor to knock the asteroid’s surface. The aim was to collect material unaffected by space radiation or other environmental conditions. The size differences suggest different hardness of the bedrock of the asteroid. One possibility is that the place of the second touchdown was a hard bedrock and larger particles broke and entered the container.
Hayabusa2 is now on another mission to a smaller asteroid, called 1998KY26. The Japanese government expects the aircraft to take 11 years to reach that asteroid. Hayabusa2’s new mission aims to study possible ways to prevent large meteorites (陨石) from hitting Earth.
1. What are these asteroid materials used to do?| A．Study how the solar system was born. | B．Determine the movement of asteroids. |
| C．Study the environment on the asteroid. | D．Uncover when the asteroid was formed. |
| A．To discover new planets. | B．To fetch more materials in space. |
| C．To travel around the solar system. | D．To explore ways to protect the earth. |
| A．They were collected in the same place. | B．They both were black and hard. |
| C．They came in different shapes. | D．They were of equal weight. |
| A．Japan Makes Progress in Studying Solar System |
| B．Japan Is Pleased with Latest Asteroid Samples |
| C．The Secret of an Asteroid Comes to Light |
| D．The Earth Faces Threats from Space |
