【推荐1】The landscape of parents staying at home is changing, challenging old ideas about who takes care of the children. While moms usually did this in the past, a recent study by Pew Research Center shows more dads are staying at home. Over the last 30 years, the number of dads staying at home has gone up from 11% in 1989 to 18% in 2021.

Economics is the most significant part of this change. As women do better in school — with 53.1% of adults with a bachelor’s degree being women and get better jobs, families are thinking about different ways to share responsibilities. Women are getting better paying jobs, like in medicine and law, making some families decide that having the dad at home and the mom as the main earner is the best choice. Chris Braaten from California knew his wife, with a higher degree, could earn more, so he happily stayed at home.

The wish for one parent to stay at home often matches what both partners want. Many dads, not happy with their jobs, find more joy in taking care of their children. Spending meaningful time with family and feeling satisfied often matter more than staying in the workforce.

The high cost of childcare is also making parents think differently. Childcare can be very expensive, ranging from $4,810 to over $15,000 per child each year. This leads some families to consider new ways, like having the dad stay home, to handle these costs.

Cannon Ingalls and Jeff Carlson show this too. Ingalls, moving from Missouri to Minneapolis, chose his wife’s better-paying job over his own. Carlson in Colorado found that most of his salary was going to childcare, so he decided to stay at home to avoid money stress.

As the idea of parents staying at home continues to change, economic factors, along with new thoughts about gender (性别) roles and a wish for more meaningful family time, are making more dads choose to stay at home.

【推荐2】Astronauts floating around Earth might soon be able to make their own delicious, creamy breakfast. This is thanks to Australian high school students. They want to see if the astronauts can make yogurt in space!

Six students from Haileybury, a high school in Melbourne are participating in a program led by some scientists. They placed the bacteria (细菌) producing yogurt in a culture (培养菌) and packed 36 containers with frozen milk and the bacteria. Then, they sent the containers to the International Space Station (ISS), where the astronauts defrosted the frozen ingredients. These students are working with the scientists to study how bacteria react to microgravity, which is only a small part of the gravity we experience on Earth.

But how exactly do bacteria make yogurt? It all starts with the bacteria that live in milk. These bacteria eat some of the sugar in milk and create a kind of acid, which makes the milk thick and creamy. This process is fermentation (发酵).

The astronauts will study these containers to see how yogurts change depending on the type of milk — either full cream cow’s milk or soy milk. They will also test different fermentation time — either 24, 48 or 72 hours.

When the yogurts come back to Earth, the students will analyze their nutrients. One Haileybury student, Chiara Sgroi said one goal of the experiment is to figure out which yogurt is the most nutritious. “We can even get to taste them, which is pretty exciting,” said Sgroi.

One day, we might be able to send astronauts with some frozen bacteria and milk. We hope that they can easily make healthful yogurt in space.

【推荐1】NASA’s Lunar Flashlight (the CubeSat), a small satellite, was launched on Dec. 1, 2022, to demonstrate several new technologies, with the goal to map ice near the Moon’s South Pole. Since then, the briefcase-size satellite’s propulsion （推进） system—the first of its kind ever flown—proved unable to generate enough force to get into lunar orbit, despite months of effort by the operations team. Because the CubeSat cannot complete operations to stay in the Earth-Moon system, NASA has called an end to the mission （任务）.

NASA relies on technology demonstrations to fill specific knowledge gaps and to test new technologies. Used for the first time beyond Earth’s orbit, Lunar Flashlight’s propulsion system and green fuel were such demonstrations. Although the propulsion system was unable to produce the desired force, the newly developed propulsion system components went beyond performance expectations.

“Technology demonstrations are, by their nature, high risk and high reward, and they’re essential for NASA to test and learn,” said Christopher Baker, the program executive. “Lunar Flashlight was successful from the standpoint of being a testbed for new systems that had never flown in space before. Those systems, and the lessons Lunar Flashlight taught us, will be used for future missions.”

The mission’s four-laser reflectometer, a science instrument that had never flown before, either, also tested successfully, giving the mission’s science team confidence that the laser would have been able to detect ice if it were present at the lunar surface.

“It’s disappointing for the science team, and for the whole Lunar Flashlight team, that we won’t be able to use our laser reflectometer to make measurements on the Moon,” said Barbara Cohen, the mission’s principal investigator. “But like all the other systems, we collected a lot of in-flight performance data on the instrument that will be incredibly valuable to future application of this technique.”

【推荐2】“You do not need to be a rocket scientist.” Americans hear these words often. People say them in schools, offices and factories. Broadcasters on radio and television often use them.

How did the expression begin? No one seems to know it.    1    “It grew,” he says. “Because rocket scientists probably are the most intelligent people around.”

Not everyone would agree.    2     For example, a person who speaks fifteen languages, or a medical doctor who operates on the brain. Still, many people would agree that there is something special about scientists who build rockets. Maybe it has something to do with the mystery of space travel.

Moving pictures from before World War Ⅱ showed a man named Buck Rogers landing on the planet Mars.    3     The rocket scientist is a different kind of hero. He or she makes space travel possible.

    4     A Washington rocket scientist told about a launch that was put off many times. Finally, everything seemed right. Mechanical failures had been repaired. The weather was good. The scientists had planned that part of the rocket would fall into the ocean after the launch. All the ships and boats within many kilometers of the danger areas had been warned. But in the last few seconds a small boat entered the area.    5    

When the work goes well, most rocket scientists enjoy their jobs. One scientist said, “As a child I loved to build the rockets. Now I am a grown-up. I still love to build rockets. And now I get paid for it.”