Did We Once Have a 5th Gas Giant Planet?

Missing Planet Explains Solar System's Structure - New Scientist 9/22/11

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After running thousands of computer model simulations of the creation and history of the solar system, it is becoming apparent to researchers that the best way to explain the current locations and orbits of the planets is to start with 5 gaseous giant planets instead of the four we know and love: Jupiter, Saturn, Uranus and Neptune. Very interesting findings and definitely gives us something to think about. We could have lost our very own orphan planet, something I wrote about the other day as astronomers have finally started to detect exoplanets without stars around them, victims of cosmic pinball that got jettisoned from their solar systems in a gravity tug of war. I don't know if there is any way to actually confirm that this is indeed what happened, but maybe we can think of some fun names in honor of our potentially missing "9th" planet... Suggestions?

Orphan Planets

Billions of Dark Planets Roam the Milky Way - The Daily Galaxy 9/20/11

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Astronomers have finally detected large exoplanets that orbit no particular stars. This was something we expected to find but until has been too difficult to detect in interstellar space. It has long been thought that after the big bang and the creation of galaxies, large and small planets alike were playing cosmic pinball amidst the immense gravitational forces as material coalesced. Many planets were destroyed in the process, some were caught in orbits around nearby stars and many were thought to have been flung into the abyss of space in between star systems to float for ages, dark and alone. In fact, many astronomers feel there are more of these orphan planets than there are regular planets around stars in our galaxy. They are just much more difficult to detect since there is no gravitational wobble or light dimming associated with a parent star (how most planets are currently being detected). Unfortunately, the story doesn't go into detail as to how these planets were detected. I would be interested to know the method for determining these bodies.

Oceans on Pluto?

Pluto's Icy Exterior May Conceal An Ocean - New Scientist 9/16/11

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Didn't see this one coming. Scientists from the University of California announce some stunning new calculations that show an ocean under the surface may be a possibility. Apparently radioactive decay of potassium in the core of the dwarf planet may create enough heat to harbor liquid oceans. NASA's New Horizons Probe may give us some more details when it does a fly-by in 2015. Until then, we will speculate and dream of the possibilities. Pluto may have some spunk after all!

Kepler Finds Tatooine

Real-Life 'Star Wars' Planet Seen

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Another really cool discovery by the Kepler telescope. Announced today, a planet, just like Luke Skywalker's home planet Tatooine, orbits a pair of stars! A double sunset was something for the imagination in 1977 but is now confirmed out in the galaxy. Binary star systems for a long time were considered too unstable to support planets, but here we are. This leaves the doors open for many more possible planets than we had previously thought, much less moons. Well done Kepler, and keep the discoveries coming as we are amazed every time we find something new!

My 2 Suns: Bounty of New Exoplanet Discoveries Includes a World Orbiting a Binary Star

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A Good Planet is Hard to Find

A Good Planet is Hard to Find

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Nice op-ed piece here by Lucianne Walkowicz on what it's like to hunt for earth-like planets orbiting around other stars. The Kepler mission has been finding tons of new planets and these astrophysicists now have very precise ways of identifying a planet, the size and distance from the star and it's chemical makeup in many cases. Very exciting field of science as we search for other life and other habitable planets for humans as we venture out into the stars.

Here is just a sample of some of the orbiting planets found so far in transit in front of their host stars: