A: Mr. Liu, can I ask you some questions about Mars?

B: Sure, go ahead.

A: Is Mars hot?

B: Mars might look red-hot. But don't let its color fool you. Mars is much farther away from the sun than Earth. So it gets less light and heat.

A: Why "Mars"?

B: Mars takes its name from the Roman god of war (罗马战神). In China, the red color makes people think of fire. So they call the planet "fire star".

A: Are there Martians on Mars?

B: Unluckily, we haven't found any "people" on Mars yet. They are kind of like Santa Clause. Nobody can see them, but many people believe they are real.

A: Will we lose weight on Mars?

B: Living on Mars could be good in many ways. For example, you might not need to go on a diet to lose weight. If you weigh 50kg on Earth, you will only weigh 19kg on Mars. This is because the surface gravity (表面重力) on Mars is only about 38 percent of that on Earth. Do you want to know your weight on Mars? Just multiply your weight by 0.38. That's it.

A: Thank you. We know a lot about Mars now.

B: You're welcome.

    As more information comes out about 10-year-old Cindy Smith's death(死亡), worries about amusement park safety(游乐场安全性) grow.

Cindy is not the first child who died on an amusement park ride. 25 years ago, the mother of a 14-year-old girl waited to pick up her daughter outside Worlds of Fun. Laura Barry never saw her daughter Rosie alive again.

"My heart goes out to the Smith family more than they can ever possibly know," said Barry. She is one of the few people who truly know the hurt that family is feeling.

In 1995, Rosie's mom said that something went wrong on the Timber Wolf the night Rosie died. Police found no evidence(证据). Two men told the police that they saw Rosie standing before she fell out of the car.

"I couldn't believe that such a thing could happen still and again," said Barry. She believes Rosie's death should have been a wakeup call for amusement park safety.

She finds that not much has changed in the past years. Amusement parks race to build bigger, taller, faster rides. In her opinion, amusement parks just try to bring in visitors and give them the idea that riding is good, safe and fun. She believes that parks should have put safety first.

There is no exact number of amusement park deaths each year. It is quite low according to some websites. But Barry doesn't accept that. "My daughter was the only person that had ever been killed at Worlds of Fun in all of the years, among all of the thousands and thousands of people that went there. The number doesn't mean anything, you know, because when your child is the one, that's one too many," she said.

It has been nearly 5 years since Chang'e-4, a Chinese spacecraft, made the first soft landing on the far side of the moon at 10:26 am on 3rd January 2019. It is the first time that a spacecraft has made it. The far side is the part of the moon that always faces away from the earth.

After it landed on the ground, the spacecraft took the first photo of the"dark side"of the moon, and sent it back to the earth through the Queqiao relay satellite(中继卫星).The scientists launched the satellite into space in May, 2018.

"What we know about the far side of the moon is from orbiters (轨道飞行器), from Russia, the US, European countries, China and India,"Andrew Coates, a professor of Physics at University College London, told a reporter. China sent Chang'e-4 into space from the Xichang Satellite Launch Centre in December,2018. Sending a spacecraft to the far side of the moon isn't easy, because the far side is covered in craters(火山口). Some of its mountains are higher than Qomolangma, the highest mountain on the earth.

What's more, we can't see the far side because it takes the moon about 28 days to move around the earth with the same side always facing our planet. Direct communication with the earth is impossible on the far side of the moon, so communications must go through a communication satellite. That was why scientists launched the Queqiao relay satellite.

Life is like a box of chocolates.You never know {#blank#}1{#/blank#}you're going to get.Not only life，so are the mystery boxes（盲盒） from a {#blank#}2{#/blank#}in Zhengzhou，Henan Province.

The museum catches visitors' eye with a series of archaeological（考古） mystery boxes.These boxes allow visitors to {#blank#}3{#/blank#}up the earth to look for replicas of cultural relics（文物复制品） {#blank#}4{#/blank#} thousands of years ago.

As the name suggests，a mystery box is mysterious，as there is {#blank#}5{#/blank#}way to know what is inside.Just for about 40 yuan，people can take their chance to dig and try to find their {#blank#}6{#/blank#}treasures.The mystery boxes come in different {#blank#}7{#/blank#}.Even if there aren't any replicas of cultural relics in a mystery box，a small gift can still be {#blank#}8{#/blank#}.The museum's first mystery boxes sold out soon，with many visitors calling for restocking（补货） online.

The museum in Henan is not the {#blank#}9{#/blank#}to sell mystery boxes with replicas of cultural relics in China.The Shaanxi History Museum in Xi'an has created its own mystery box models based on relics from the Shang and Zhou Dynasties.What's also {#blank#}10{#/blank#}are the mystery boxes from the Sanxingdui Museum in Sichuan.

The museums are using their creative products {#blank#}11{#/blank#}ancient Chinese stories.It's a great way for young people to get to know about our history and culture.

A handwritten letter by a little boy asking Santa for a "very good dad" has captured hearts worldwide.

The boy, known only as "Blake" in the letter, wrote, "Dear Santa, We had to leave our house. Dad was mad. We had to do all the chores. Dad got everything he wanted. Mom said it was time to leave and she would take us to a safer place where we don't have to be scared.

"Blake is a 7-year-old boy in one of our shelters, and his mom found this letter in his backpack..."Posted by SafeHaven of Tarrant County on Wednesday, December 18, 2019.

"I'm still nervous. I don't want to talk to the other kids," he continued. "Are you going to come this Christmas? Can you bring a dictionary, and a compass and a watch?"

The most heart-breaking part of the letter was the last line that read, "I also want a very very very good dad. Can you do that too?" 

Officials with SafeHaven of Tarrant County, a group seeking to help end domestic (家庭的) violence（暴力）, posted Blake's letter to its Facebook page. Now, some of the child's wishes have come true. All of the gifts he asked for have been donated by people in the community. Though SafeHaven received more than 10,000 gifts this year, they want to shine a light on the bigger issue of domestic violence.

"To us, it was kind of a story that we've heard all the time," Kathryn Jacob, the organization's president and CEO, told Today. "Like tonight, we have 73 kids in the shelter.""Blake is just one of many."