Massive Planet Gone Rogue Discovered

In this artist's conception, a rogue planet drifts through space. Credit: Christine Pulliam (CfA)

A massive rogue planet has been discovered in the Beta Pictoris moving group. The planet, called PSO J318.5338-22.8603 (Sorry, I didn’t name it), is over eight times as massive as Jupiter. Because it’s one of the few directly-imaged exoplanets we know of, and is accessible for study by spectroscopy, this massive planet will be extremely important when piecing together the details of planetary formation and evolution.Most planets outside our solar system are not directly observable. They are discovered when they transit in front of their host star. That’s how the Kepler mission finds exoplanets. After that, their properties are inferred by their gravitational interactions with their star and with any other planets in their system. We can infer a lot, and get quite detailed, but studying planets with spectroscopy is a whole other ball game.The team of researchers, led by K. Allers of Bucknell University, used the Gemini North telescope, and its Near-Infrared Spectrograph, to find PSO’s radial and rotational velocities. As reported in a draft study on January 20th, PSO J318.5338-22.8603 (PSO from now on…) was confirmed as a member of the Beta Pictoris moving group, a group of young stars with a known age.The Beta Pictoris moving group is a group of stars moving through space together. Since they are together, they are understood to be formed at the same time, and to have the same age. Confirming that PSO is a member of this group also confirmed PSO’s age.Once the age of PSO was known, its identity as a planet was confirmed. Without knowing the age, it’s impossible to rule it out as a brown dwarf, a “failed star” that lacked the mass to ignite fusion.This new rogue planet is 8.3 + or – 0.5 times the mass of Jupiter, and —> Read More

Gravity Waves and ET

The other shoe has dropped.

After a century of speculation and a half-century of searching, science teams using instruments built by Caltech and MIT have made a discovery that will take up permanent residency in physics textbooks from now to the end of textbooks. They’ve found the gravity waves that Einstein’s General Theory of Relativity predicted must pervade the cosmos.

There’s little doubt that this experiment should be celebrated. It’s a triumph of perseverance and clever effort: the instrumentation involved is able to detect distortions amounting to a millionth of a billionth of a meter in a tube four kilometers long. That’s like measuring the distance to Mars with a precision greater than the thickness of a bacterium’s cell wall.

Once more, Einstein’s concept of space-time has been vindicated, and while pundits love to talk about how incomplete science is and how little those pointy-headed academics know, this discovery indicates that there are things we do know. Important things, such as the behavior of space and time.

This is a story about physics, of course. But although one seldom hears “extraterrestrial intelligence” and “space-time continuum” in the same breath (unless you’re a Dr. Who fan), there’s a perceived connection between the two subjects.

I often get correspondence from folks who think that listening for radio signals or looking for laser flashes are fundamentally flawed approaches to hunting down evidence for alien beings. The extraterrestrials, these people suggest, will have moved on to a more avant-garde communication mode: gravity waves.

There are, indeed, some positive arguments for aliens with a penchant for palaver to opt for gravity wave communication. Gravity waves can travel unhindered through the dusty material that suffuses interstellar space — unlike laser light. And gravity waves aren’t distorted and scattered by the ionized gas that clutters the cosmos —> Read More

1 2 3 5,450