LAB11 LIFE IN THE UNIVERSE.docx - 1 LIFE IN THE UNIVERSE...

This preview shows page 1 - 2 out of 3 pages.

Info icon Subscribe to view the full document.

Unformatted text preview: 1 LIFE IN THE UNIVERSE Astronomical researchers and planetary researchers are still looking for life in our solar system and the rest of the cosmos. Several of science's most perplexing issues revolve on how much life there is in the universe and what manifestations it may take. In this essay, I'll go through two different types of searches. The first involves direct investigation of planets inside our own solar system, particularly Mars. Secondly, and considerably more challenging, objective is to look for signs of life on planets orbiting other stars. LIFE ON MARS There has been a rich and deep history that Mars has the possibility to have hosted life, or is hosting life. This history dates back to the canals that individuals/astronomers reported to observe on the surface of Mars towards the end of the 19th century and the start of the 20th. With the beginning of the scientific revolution came the opportunity to investigate this concern more closely through a series of exploration of Mars, which originated with the very first effective and successful robotic spaceship mission in 1964 and culminated in the implementation of NASA's Space probe, which touched down on Martian' ground in 2012. Early Mars missions hinted that liquid water—one of life's most basic requirements— might have flowed on the surface, and subsequent deployments to mars have confirmed this finding. In 1976, the NASA Viking space probes landed on Mars with the mission of looking for concrete signs of life. Viking's soil research showed nothing regarding whether life lived on Mars in the ancient history, when water was more plentiful. We certainly understand that water in the form of ice is abundant on Mars, but only at a shallow depth under the crust. The atmosphere of Mars contains water vapor as well. Our knowledge of Mars has increased dramatically since 2 Viking's arrival. The existence of compounds that could only have grown in the presence of liquid water has been found by orbital satellites, which have produced ever-more precise photographs of the ground. This is an excellent indicator of life's existence. LIFE ON PLANETS ORBITING OTHER STARS Astrobiologists have established the concept of a habitable zone—a area around a star where favorable parameters for life may exist—to evaluate the likelihood for life in faraway planets and stars. The habitable zone is commonly conceived of as the range of spatial distance from the central star in which water might be present in liquid form at the surface of a planet, and it concentrates on life's necessity for liquid water. Venus, for instance, has crust temperatures that are much above the water's boiling point, whereas Mars' surface temperatures are almost usually just under water's freezing point. The surface temperature of Earth, which orbits between the two, is "exactly perfect" for keeping much of our ground water in liquid form. The brightness of stars like the Sun grows during their main-sequence lifetimes, which implies that as a star system matures, the habitable zone moves outward. The Sun's power output, for instance, has grown by a minimum of 30% during the last 4 billion years, according to estimates. As a result, Venus was previously habitable, whereas Earth got inadequate solar energy to keep the contemporary Earth (with its current atmosphere) against freezing. Researchers have been trying to comprehend all of the parameters that determine the habitable region and the livability of planets orbiting inside it, as this will be a major guide in locating exoplanets to search for signs of life. As our ability to identify exoplanets has improved, so has our ability to discover Earth-size planets within their parent stars' habitable zones. 3 ...
View Full Document

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture