Astrobiology, The Future.

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Space Travel

I am still trying to decide whether my admiration for Elon Musk is because of his electric vehicles (S-3-X-Y) or his passion for space exploration. The topic of space exploration leads me to a scientific field I would like to talk about briefly, Astrobiology. Wikipedia defines Astrobiology as “an interdisciplinary scientific field concerned with the origins, early evolution, distribution, and future of life in the universe.” I am not an Astrobiologist but I do know that what is keeping professionals in the field awake at night is the question of whether extraterrestrial life exists, and if it does, how humans can detect it. To do this, Astrobiologists make use of molecular biology, biophysics, biochemistry, chemistry, astronomy, physical cosmology, exoplanetology and geology to investigate the possibility of life on other worlds. They also try to recognize biospheres that might be different from that on Earth.

Thanks to the use of high level automated systems for space missions, space exploration has become easier. According to Wikipedia, these high level automated systems “yield benefits such as lower cost, less human oversight, and ability to explore deeper in space which is usually restricted by long communications with human controllers.” How much progress have we made in determining whether extraterrestrial life exists? Ever since landing on the moon, Mars has been a focal point of modern space exploration. According to Aerospace.com, “Mars exploration is a long-term goal of the United States. NASA is on a journey to Mars, with a goal of sending humans to the Red Planet in the 2030s.” NASA and its partners have sent landers, orbiters, and rovers to help it increase its knowledge about the planet.

It is worth mentioning that only three countries have human space programs (China, Russia and the US). It costs a lot to have such a program! Additionally, there is more competition between these countries than is healthy. Even though the International Space Station (ISS) is a massive collaboration between five space agencies (Nasa, Roscosmos, Japan’s Jaxa, the pan-European agency ESA and the Canadian Space Agency), we have a powerful and resourceful country like China trying to ride solo. As a matter of fact, it is reported that “in 2006, Beijing reportedly tested lasers against US imaging satellites in what appeared to be an attempt to blind or damage them, and US lawmakers later banned cooperation between Nasa and China’s state agency.” But I am hopeful that the ISS is strong and resourceful enough to embark on many more groundbreaking missions.

Retrograde Motion simplified.

the path of mars

The path of Mars, as viewed from the Earth.

         Retrograde motion is the apparent backward motion of a planet caused by its being lapped by another planet, or vice-versa.1  These two planets are usually on two different orbits, a larger one and a smaller one, and they move around the sun in the same direction (eastward). The planet on the smaller orbit moves faster than the planet on the larger orbit. When the two planets on different orbits do overlap, and align with the sun, either one of the planets sees the other planet as moving in the opposite direction. However, this is only an apparent motion, as the planets are truly moving in the same direction. This apparent motion is what we call “retrograde motion.” The period between two retrogradations is the synodic period of the object/planet.2 A practical example of retrograde motion is the motion that when you pass a car on the freeway. The car being passed appears to move backwards relative to you. Alternatively, you can experience this by standing side by side with a friend, and having them. walk forward slowly. Now walk forward at a faster speed and watching your friend, think about how they are moving relative to you. At first, they move away, then as you pass them, they appear to be moving backward relative to you – even though they are still walking forward. Ancient Greek astronomer Ptolemy in 150 AD believed that the Earth was the center of the Solar System and therefore used the terms retrograde and prograde to describe the movement of the planets in relation to the stars, and the names have remained since then.3