Archive for January, 2009

Could life exist on Super-Earths?

Wednesday, January 7th, 2009 by Evan Finnes

The search for extraterrestrial life within our solar system has mainly been focused on Mars, and there has been speculation that some the moons of the outer solar system may also be a good place to look for life. Outside of our solar system, planet hunters and astrobiologists have been searching for Earth-like planets to help answer one of mankind’s most profound questions, “are we alone?” To date, no such planets have been discovered, so a team of scientists have now set their sights on a relatively abundant group of extrasolar planets known as “super-Earths”.

The term “super-Earth” is slightly misleading because the only thing that these planets have in common with the Earth is the fact that they are terrestrial. A super-Earth is typically classified as a terrestrial planet with a mass of 5 to 10 Earth masses. Thus far, Super Earths have not been found within the habitable zone of their host star, with orbits much too far or much too close to sustain life as we know it. The super-Earths with orbits far from their host star are the places that astrobiologists now believe could harbor some form of life.

It is estimated that one-third of all solar systems contain super-Earths, and some scientists believe that it may be possible to find some that have liquid water either on the surface, or below a thick layer of ice. This water could theoretically exist on a super-Earth if one of three conditions were met. 1) If the planet had a thick enough atmosphere it may be possible that enough solar radiation could be by greenhouse gases to prevent water from completely freezing. 2) If the planet was massive enough or young enough, there may still be enough primordial heat available to sustain some amount of liquid water.

Currently, the best technique for discovering super-Earths is by using gravitational microlensing. This phenomena occurs when an object in the foreground has enough mass, its gravitational field will bend the incoming light of a much more distant object. This results in the magnification of the distant object, no matter how faint it may seem.

It is not unfathomable to predict that an extrasolar super-Earth outside of its host stars habitable zone could contain water, at least as ice. Much of the ice in our own solar system is located outside of the habitable zone. There is no super-Earth in our solar system, but there are icy bodies that could contain liquid oceans. It is hypothesized that Jupiter’s moon, Europa, may have enough heat due to tidal flexing to permit a liquid ocean.

Traveling amongst the stars and exploring extrasolar planets is unfortunately not in the near future, but we can test hypothesis such as this one by exploring the planets within our solar system, and isn’t it about time we send a probe to Europa?

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OUU Podcast #5: Something from Nothing

Monday, January 5th, 2009 by Aridian PR
Our Undiscovered Universe Podcasts

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OUU Podcast #5: Something from nothing

Welcome to the fifth in a series of podcasts that explore Null Physics as presented in the book, Our Undiscovered Universe, written by Scientist and Engineer, Terence Witt.

The topic of discussion today is “Something from nothing”, discussing various cosmology theories like the big bang and how they compare to the theory presented using Null Physics.

Also in Episode 5:

  • How does science address new ideas?
  • What role does the Big Bang play when scientists are looking for an alternative theory?
  • How did Null Physics evolve to the theory it is today?
  • What is the difference between a steady state universe of null or zero, and the theory that one began as zero then exploded with a bang?
  • Also available on iTunes! Search “Null Physics” and Subscribe Now!

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    International Year of Astronomy

    Monday, January 5th, 2009 by Bellatrix

    Now that 2009 has begun its important for all to know that 2009 has been declared the international year of astronomy. It is the 400th anniversary of when Galileo Galilee first turned his telescopes to the heavens, opening a whole new world of scientific discovery. It is an important time to remind and education the public about the world of astronomy, with astronomy budgets tightening getting the public involved is crucial to keeping support alive and well.

    The history surrounding Galileo is quite fascinating and worth looking into for any science or history enthusiast. He was truly one of the first real scientists, pioneering what we know as the modern scientific method. Galileo lived an interesting life teaching mainly in Pisa Italy (where he did the famous experiment of dropping objects of different weights off the leaning tower) and then spending the majority of his life in Florence. In Florence he spent his time educating the ruling family of the time, the Medici. He did not invent the telescope as many think, as it was first invented for use as a naval navigation tool. He was the first to use it for astronomical purposes. With his telescope he discovered the moons of Jupiter and documented sunspots, the phases of Venus, and made detailed drawings of the surface of the moon. For anyone interested a terrific read on the subject is the book ‘Galileo’s Daughter’ by Dava Sobel. It is a good biography not just of his professional but also personal life and includes real transcripts of letters between him and his daughter; it gives a good view of life in Italy at the time.

    Back in 2009, many events will be happening throughout the year to commiserate this occasion. For a full list check out the official website at www.astronomy2009.org. The kick off will officially be in Paris on January 15 and 16 featuring keynote speeches from Nobel laureates and video feeds from scientists all over the world. The solar physics group will be having a yearlong campaign in over 30 countries at 150 different venues. ‘The Cosmic Diary’ is a website being launched in January focusing on the daily lives of astronomers with over 50 astronomers from 35 countries participating with blogs, articles, video, and more. Another event is the ‘100 Hours of Astronomy’ taking place on April 2-5. It will feature live web casts, public viewings, and other outreach events. One interesting feature going on the month of January is the project ‘Dark Skies Awareness’, where the International Year of Astronomy organization is trying to rise awareness about light pollution and they’ve called on the public to count the number of stars that are visible in areas with differing light pollution and you can then compare with there data on the number of stars when there is no light pollution and the results are quite surprising.

    I personally encourage anyone reading to get involved. There are many ways for the public to get involved in astronomy. You can head out to your local planetarium and see what they have going on. Or go to a public viewing night held by your local university or observatory. I know some university’s go out into the community and do things like Universe in the Park viewing nights, or if you have children you can sign up their class or troop to have astronomy students come do a presentation. If you already have a telescope just take it out and make sure it gets some use, and if you know how try hooking up your camera to it and enter an astronomy picture contest. Astronomy is a fascinating subject, but in difficult financial times its important to keep the public enthused involved and educated, hopefully with some of these large scale events going on people will get reminded just how fun and amazing it can be to look up to the heavens as Galileo did so many years ago.

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