It seems that we are one step closer to finding alien life and maybe a future home for humanity. Scientists from NASA have found a new solar system filled with planets that look like the Earth and could even support life.

The group of seven planets, which orbits a star called Trappist-1, is 39 light years away from the Earth in the constellation of Aquarius (水瓶座). And three of them are in the “habitable zone” — the area around a star where water is most likely to be found. This is important because water is necessary for life.

“This is an amazing planetary (行星的) system, not only because we have found so many planets, but because they are all surprisingly similar in size to the Earth”, astronomer Michael Gillon from the University of Liege in Belgium told The Independent.

Trappist-1 is a “dwarf star (矮星)” which is colder and shines dimmer than our sun. If a person were on one of the seven planets, everything would look a lot darker than usual. The amount of light heading toward our eyes would be about 200 times less than we get from the sun, according to The Independent.

Because of that, Trappist-1, together with many other dwarf stars, was never on the list of places where scientists looked for alien life. But Michael Gillon, lead researcher behind the discovery, decided to give dwarf stars a chance. He built a telescope in Chile to observe 60 of the closest dwarf stars, and it turned out that Trappist-1 was worthy of the effort.

The researchers hope that they can spend more time watching the newly found planets to learn more about them. Even though more research is needed before determining whether these planets could really support life, the discovery is still encouraging. It shows just how many Earth-size planets could be out there.

“The discovery gives us a hint that finding a second Earth is not just a matter of if, but when,” NASA scientist Thomas Zurbuchen told The Telegraph.

The journey to the moon has been the first step towards future exploration in space. The distance between the Moon and Earth is very short indeed when compared with the distances between Earth and the other planets. Mars, the nearest planet to Earth is millions of miles away! Travelling to the planets will be man's next aim. Such travels will be more challenging than the trip to the moon and certainly more adventurous.

Recently, two American spaceships, Vikings 1 and 2, landed on Mars trying to discover whether that planet has any life on it. So far the signs of life on Mars has neither confirmed nor ruled out. Russians have discovered that the surface of Venus（金星）is so hot that it is almost certain that there is no life there. Also the atmosphere of Venus is extremely dense and the pressure is nearly a hundred times greater than that of the Earth's atmosphere.

Scientists believe man may find planets which have the same conditions as those we have on earth, but man should realize Earth will be his only home for a long time and begin to love and care for it.

The earth has many mysteries for people to explore and we live on the earth for protection. Do you know that the earth has two North Poles? There’s the geographic North Pole, which never changes. And there’s the magnetic (有磁性的) North Pole, which is always on the move. Over the past 150 years, the magnetic North Pole has casually wandered 685 miles across northern Canada. But right now it’s racing 25 miles a year to the northwest. This could be a sign that we’re about to experience something humans have never seen before: a magnetic polar flip (翻转). And when this happens, it could affect much more than just your compass.

Right now on the surface of the planet, it looks like it’s just a bar magnet. Our compasses are just pointing to one pole at a time because there’s mainly a two-pole system. But sometimes, the earth doesn’t just have a single magnetic North and South Pole. Evidence suggests that, for hundreds to thousands of years at a time, our planet has had four, six, and even eight poles. This is what has happened when the magnetic poles flipped in the past. And when it happens again, it won’t be good news for humans.

Now you might think, eight poles must be better than two. But the reality is that multiple magnetic fields would fight each other. This could weaken the earth’s protective magnetic field by up to 90% during a polar flip.

The earth’s magnetic field is what protects us from harmful space radiation which can damage cells and cause cancer. With a weaker field in place, some scientists think this could expose planes to higher levels of radiation, making flights less safe.

This could also interrupt the internal sense of direction in many animals that use the magnetic field for navigation (导航). Even worse, it could make certain places on the planet too dangerous to live in. But what exactly will take place on the surface is less clear than what will undoubtedly happen in space.

Satellites and space missions will need extra shelter that we’ll have to provide ourselves. Without it, intense universal and solar radiation will fry circuit boards and increase the risk of cancer in astronauts.