Ex-President Barack Obama has become more popular because of his tweet about an attack in Virginia. The most liked tweet was a line from Nelson Mandela’s book, “Long Walk to Freedom.” It said, “No one is born hating another person because of the color of his skin or his background or his religion. People must learn to hate, and if they can learn to hate, they can be taught to love, for love comes more naturally to the human heart than its opposite.”

The line was divided into three tweets. One of them has a photo of Obama greeting children through a window in Maryland.

A Twitter staff said, the most liked tweet before that was from Ariana Grande about an attack in her concert. It was beat by Obama’s tweet which was liked more than three million times.

Scientists from Brown University have discovered that there is a good bit of water inside the moon. According to the associate professor at Brown University, they found water trapped in glass beads. These beads are from the ashes and rocks of volcanic eruptions. They have also mentioned that almost all of the volcanic materials show signatures of water which means that a large part of the moon is wet.

In 2008, the volcanic beads that were brought back by the Apollo in 1971 and 1972 were examined. They found crystalline formations that contain water. However, they were unsure if these samples represented either the whole moon or just a small part of it. To confirm this, they studied the samples again. They were able to gather more evidence to prove that the volcanic materials were spread all over the moon.

Some people believe that ancient Egyptians knew the principles of flying. With the discovery of the Saqqara Bird in 200 B.C, people thought of it as an actual aircraft model because ancient Egyptians often put models of actual inventions in tombs. A model based on the Saqqara bird’s design was tested and was discovered that it could have flown. Thousands of years after that, a part of an ancient writing system that seems to be a helicopter was seen in the Temple of Seti The First built at around 1280 B.C. However, what ancient Egyptians knew about aircraft remains unknown.

The Quimbaya civilization which existed halfway across the world is what is now called South America. They are popular for their gold antiques. Among them was an airplane-like antique, which was possibly a model of a bird or an insect. However, some people believed that it can fly so in the 1990’s, it was tested with an engine and it flew above the ground.

About the same time with the Quimbaya civilization, the Mayan civilization existed. Some people thought that the ancient Mayans are familiar with space travel because of Pakal I’s tomb. Pakal I ruled from A.D. 615 to 683 and was buried in a spaceship-like tomb. Until now, the mystery behind the ancient models has not been solved.

Have you ever imagined connecting nine dots in three rows and three columns with no more than three straight lines? And the lines have to cross through all nine dots? Do you think it would be possible? For some people, it would be impossible. But if they would challenge their guesses, they would realize that one way to do that is by cutting the dots and lining them up in a straight line.

Thomas Edison, an American inventor and businessman, would usually offer a bowl of soup to applicants during the interview. He wanted to see if they would put salt to the soup even without tasting it first. This way, he would know who would rely too much on guesses. He did not want to hire people who do not consistently challenge the way they think.

Taking guesses affects numerous possibilities. It precludes effective solutions to the problems. That is why it is important to give emphasis on challenging the way they think. However, many things have been taken for granted. For instance, everyone would think that a lake is freezing cold, so no one ever dares to dive into the lake. People would never find out the truth unless they dive into the lake. If people would be able to consistently challenge the way they think, they could extend possibilities and find long-term solutions to their problems.