In or Out? Has Voyager left the solar system?

San Francisco - There is a possibility that Voyager, the U.S. spacecraft launched in 1977, which is thought to have left the heliosphere and entered interstellar space last year, could still be "inside," said Ed Stone, Voyager project chief scientist, today at the annual meeting of the American Geophysical Union in San Francisco.

09 Dec 2013

How strong was the Carrington Event?

NASA has described the magnetic field of the coronal mass ejection (CME) associated with the 1859 Carrington Event, the largest solar storm ever detected, as “extremely intense” relative to other CMEs. The amount of plasma it ejected is difficult to estimate, but more important in determining its strength is how fast it arrived.

21 Jan 2013

Benchmarks: January 1, 1960: The Discovery of "Extinct Radioactivity" The quest to date the elements that formed the solar system

On June 30, 1918, Leo Kern saw a fireball blaze across the sky above his farm near Richardton, N.D., lighting up the night sky as if it were daytime and then exploding with a deafening boom that shook houses and rattled windows. Kern ducked behind a telegraph pole as fragments that sounded like “whistling bullets” struck his barn, he later reported to geologist T.T. Quirke of the University of Minnesota. What Kern and other witnesses all over  the southwestern corner of the state had seen was a 90-kilogram meteor entering Earth’s atmosphere and breaking up 100 kilometers above the surface. Kern had no way of knowing it at the time, but he had also witnessed the arrival of a message from the dawn of the solar system — one that scientists wouldn’t decode for another 42 years. 
01 Jan 2013

Down to Earth With: Jacob Haqq-Misra

Jacob Haqq-Misra is all but addicted to music, which is why the astrobiologist balances his time between research and performing as a percussionist and vocalist with the psychedelic jam band, Mysterytrain.

18 Nov 2012

Voices: Riding the dragon: Commercial space exploration

“Looks like we’ve got us a Dragon by the tail.”

So said astronaut Don Pettit upon the successful capture of the SpaceX Dragon capsule by the robotic arm on the International Space Station (ISS) in May, heralding a revolution in space exploration with a bit of humor. We have entered the era of private spaceflight, and just in time.

01 Sep 2012

Blogging on EARTH: Curious to watch Curiosity land on Mars?

Sunday night will bring excitement to households around the world, not only because of the Olympics (and the GEOlympics), but also because the Mars Science Laboratory, also known as the Curiosity rover, will touch down on the Red Planet.

02 Aug 2012

Blogging on EARTH: Rarity the only reason for Venus transit fever?

If you read one or more stories leading up to yesterday’s transit of Venus across the face of the sun (or if you followed #VenusTransit on Twitter), you likely learned that the transit is akin to a solar eclipse — when the moon crosses directly between Earth and the sun, temporarily blocking part or all of the latter from our view — with the caveat that Venus only blacks out a small dot of the sun because of its distance from Earth. So what was all the fuss about? What was it about the celestial equivalent of watching a marble roll slowly across a dinner plate that brought people out in droves, from professional and amateur scientists to casual observers and families with young children?

06 Jun 2012

Down to Earth With: The Geographers of the Solar System

Certain government officials have super cool titles: for example, Planetary Protection Officer (NASA's Catharine Conley) and Oceanographer of the Navy (David Titley). I think Geographer of the Solar System would be right up there. Alas, no one actually has that title, but in a little-known office of the U.S. Geological Survey (USGS) nestled in the hills above Flagstaff, Ariz., I met a dozen or so people who could reasonably qualify for it.

13 May 2012

North star loses mass but still shines bright

The North Star, the Pole Star, the Guiding Star, Polaris: Its many names reflect the many centuries humans have gazed northward to it for guidance. Because Earth’s North Pole is aligned with Polaris’ position in the sky, the star appears motionless, providing a steadfast beacon for early sailors and adventurers alike. But the star itself is far from motionless. In fact, Polaris is a specific type of star known as a Cepheid variable, which pulsates, varying in size and luminosity over a period of days and, according to recent observations, also ejects large amounts of mass into space.

03 May 2012

Blogging on EARTH: Webb Space Telescope ensnared in political drama

Perhaps you have heard of the psychological principle of entrapment. In college, a friend of mine once described it to me while we stood in a seemingly endless line in one of the dining halls. As I recall, the essence of it is that the more money, time or effort you invest in some venture waiting for a return — a sandwich in my case — the harder it is to simply let it go or give up hope, regardless of how unfavorable the potential cost-benefit ratio is.

13 Jul 2011