A2: Microbes in the News

Article: 7 Alien ‘Earths’ May Be Swapping Life via Meteorites

Link: National Geographic, Mar 22, https://news.nationalgeographic.com/2017/03/earth-planets-aliens-life-panspermia-space-science/

Summary: On Feb 23, NASA reported that they found other solar system about 39 light years away from our solar system, called TRAPPIST-1 and some of planets in TRAPPIST-1 have liquid water. This release gave a shock to the world and someone may think that extraterrestrial life is existing now. According to the new research from Manasvi Lingam and Abraham Loeb of the Harvard-Smithsonian Center for Astrophysics released on Mar 15 that seven planets in TRAPPIST-1 is condensed around the stellar host so that the seeds of life can jump from one planet to other planet by debris. This research support the theory of panspermia, which maintains the origin of life came from the space to Earth. In TRAPPIST-1, all planets are located close to each other and distance between them is much shorter than the distance between Earth and Mars, so it’s easy to approach to other planets in TRAPPIST-1. Also, three planets out of seven planets may have liquid water and is located in habitable zone, so they think if they have moderate temperature and atmosphere, life can exist there. However, some astronomers are suspicious of this because they think life can’t stand the harsh condition while they are traveling. In the space, there are lots of cosmic rays and they can be exposed for more than million years. In addition, they receive a huge shock when they land on some planets. Though some member in the team says it’s really difficult to survive in the harsh condition, but some organism like extremophiles can overcome it. They don’t find plausible evidence yet, but it is a good chance for us to think about what is panspermia theory and where life come from.

Connection: The idea of ubiquitous is relate to this article. It is also relate to the origin of life(LUCA).

Critical analysis: Discovering of the TRAPPIST-1 was amazing. However, I’m wondering how microbes can jump from one planet to the other. This news said some researchers thinks it’s difficult for some microbes to survive in the space for long time due to UV or cosmic rays. While, other researchers says extremophiles can survive because some has tolerance for UV or heat. I’m suspect for this idea. If microbes can jump to other planet, we can find microbes from meteorites which come to the earth. Inside the meteorites, there are lots of Carbon sources, but their shock when land on some planet or heat can sterile them. However, the distance between one planet to the other is shorter than the distance between the Earth and Mars. Therefore, maybe, if their travel is short, some may survive and land on other planet, but it’s rarely happened.

Question: Why it support panspermia theory? How to jump to other planet from the ocean in the planets in TRAPPIST-1?