Going Up?

Imagine a 100,000 km elevator ride with the gentle beats of muzak slowly infiltrating your mind, while simultaneously your nostrils are attacked by the pungent scent of cheap perfume and the body odor of your fellow passengers. Some people might consider this to be torture, but chances are the assaults on the other four senses will be blocked out by the visual delight of the Earth slowly shrinking into a magnificent blue sphere; a view which is currently only experienced by a select few.

The idea of an elevator into space is not new. Konstantin Tsiolkovsky was the first to publish the idea in his 1895 paper: “Day-Dreams of Heaven and Earth”. It has also appeared in several Science fiction novels by authors such as Arthur C. Clarke. In a relatively short period of time, this idea has gone from an impossible dream to something that the Lift Port Group believes could happen within 23 years.

To reduce climate risks the elevator will be located somewhere along the equator, where it will climb a 100,000 km ribbon to a space station which will act as a counterweight. This ribbon is the main technological hurdle which needs to be surpassed in order achieve this dream. Carbon nanotubes appear to be the answer and experts say that the technology to build strong enough fibers may be reached in the next couple years.

An elevator to space would have many benefits. An estimated cost of delivering cargo to orbit is only $100/lb compared to current costs of up to $60,000/lb. The savings in cost would improve exploration as more money could be spent on instruments. An elevator to space would ultimately open the doors to space tourism, mining and any number of other entrepreneurial adventures.

If the technological requirements are met, will financial and legal issues prevent the timely construction of one of mankind’s greatest dreams? Or could my generation be riding an elevator to our low-gravity retirement homes?

Could Saturn's Moon Enceladus Harbor Life?

Saturn’s sixth largest moon, Enceladus, was discovered in 1789 by British Astronomer William Herschel. With a low albedo and close proximity to Saturn, Enceladus is difficult to observe. Because of this difficulty little was known about this moon until the Voyager flybys in the 1980’s. Voyager 1 discovered that Enceladus is located in the densest part of Saturn’s E Ring, and Voyager 2 discovered that Enceladus has diverse and relatively complicated surface features.

In 2005 Cassini discovered that Enceladus is the fourth known body in the solar system with active volcanism. The other three are Earth, Jupiter’s moon Io, and Neptune’s moon Triton. This volcanism causes icy jets, plumes of water vapor, and other materials to be shot into the atmosphere. It is this cryovolcanism which was determined to be the cause of Saturn’s E Ring. Just recently Cassini photographed the volcanic southern pole. These pictures revealed a geological feature which scientists are calling “tiger stripes”. These tiger stripes are 300 meter deep fractures and are surrounded by chunks of ice, and are the source of Enceladus’s
volcanism.

During a recent flyby, Cassini was able to detect ammonia within these icy plumes. This ammonia would allow water to remain in its liquid phase at lower temperatures than are normally allowed under the moons temperatures and pressures.

Cassini also discovered the cause of the tectonic activity. Enceladus, like many other moons is traped in orbital resonances, this causes tidal heating on the moons interior. Like thought to exist on Jupiter’s moon Europa, this could also cause Enceladus to have a subsurface liquid ocean. Because of the volcanic activity a subsurface ocean on Enceladus is thought to be only tens of meters beneath the surface, where the oceans on Europa are thought to be 100 kilometers beneath the surface.

Does Enceladus have a subsurface ocean? If it does, is this another place to look for signs of life? The moons ability to retain liquid water at lower than normal temperatures, and the discovery of organic materials within icy the plumes suggests that Enceladus could be one place worth searching for extraterrestrial extremophiles.

The Kepler Mission

Since the dawn of intelligent man, we as a race have asked several questions pertaining to the heavens, and to the meaning of life. In 2012, NASA’S Kepler Mission will bring us one step closer to answering one of these timeless questions: “are we alone?” Launched in March of this year, the Kepler Mission was not only named after the great mathematician and astronomer, Johannes Kepler, it also celebrates the 400th anniversary of the publication of his first two laws on planetary motion.

The Kepler spacecraft will search for Earth-like planets using a technique known as the Transit Method of Detecting Extrasolar Planets. A transit occurs when a planet crosses in front of its host star as viewed by an observer. These transits dim the brightness of a star which allow for the detection of extrasolar planets. This change in brightness is very difficult to detect by terrestrial planets, such as Earth, because they only dim their host star by 100 parts per million, lasting only 2 to 16 hours. In order for an extrasolar transit to be observed from our solar system, the orbit must be viewed edge on. The probability of observing such a planet is less than 1%. To increase the chances of observing a transiting terrestrial planet, the Kepler spacecraft will observe 100,000 of our neighboring stars. Because any planet in the habitable zone will require an orbit close to that of one Earth year, Kepler will need to observe any transits discovered amongst these 100,000 stars for at least 3.5 years to determine if the transit is periodic enough to be a planet.

The precision of the spacecraft was recently tested by observing a known exoplanet called HAT-P-7. This planet orbits a star 1000 light years away in approximately 2.2 days. Not only was Kepler able to observe transit with the precision necessary for the detection of an Earth sized planet, the light given off by this planet was also observed. This is the first time light from an exosolar planet has been observed, this light can provide information about the planet’s atmosphere.

The Kepler Mission may not be able to directly determine whether or not we are alone in the universe, but it will be able to tell us if we have neighboring planetary systems, containing planets, capable of sustaining life. When compared to all the stars in the universe, even one discovery amongst the relatively small sample space of 100,000 stars will be significant enough for us to rethink our meaning and place in the universe.