UNH to analyze 'bellwether' solar event data from European satellite

May 31, 2012
The Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics, or PAMELA, satellite. Credit: PAMELA mission.

When the sun launched a moderate, or M-class, solar flare May 17, 2012, it was still one of the largest eruptions seen since late January when our star began to rouse from an anomalously long quiet period. But the event was not just an additional solar wake-up call; it produced something that has the solar physics community puzzled and scientists from the University of New Hampshire poised to analyze a singular dataset gathered during the event by a European satellite called PAMELA – short for Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics.

The puzzle is this: The solar event created what is known as a ground-level enhancement (GLE), which is a blast of high-energy particles registered by ground stations on Earth after a very large solar flare and/or another explosive mechanism known as a coronal mass ejection (CME). The May 17 GLE lit up ground stations (neutron monitors) all over the world for the first time in nearly six years, but given the stature, or lack thereof, of the solar explosions, there should have been no GLE at all.

Says James Ryan, an astrophysicist at the UNH Space Science Center (SSC) and UNH co-investigator on the PAMELA mission, "This solar flare was most unimpressive and the associated CME was only slightly more energetic. And looking at it optically, it was remarkably dim, it was, all things considered, a ninety-eight pound weakling of solar events."

Enter PAMELA, which as luck would have it "looks" at an energy range of particles not seen by any other spacecraft. The data PAMELA recorded on the May 17 solar event should provide scientists with an unprecedented view of how the high-energy particles morphed through time and space, and this should provide insight into the mysterious appearance of the GLE.

PAMELA is a mission carried out by a European collaboration led by Italy and Russia together with German and Swedish institutes, and collaborators in the U.S. at UNH, New Mexico State University, and NASA's Goddard Space Flight Center. Launched in 2006 and dedicated to studying cosmic rays, just two weeks before the most recent blast from the PAMELA was retasked to focus on solar physics due to the sun's ever-increasing activity.

For decades, there has been strong debate as to what complex processes produce the extremely energetic particles that are registered on the ground; is it the shockwave in front of a CME or do the particles come from the itself? The most recent event has the potential to be a "real bellwether" according to Ryan because it will allow the study of the evolution of the flare from low to high energies without interruption.

"The PAMELA satellite provides us with a bridge that has never existed before," says Ryan, "a bridge between solar energetic particles measured by other spacecraft and those made on the ground by neutron monitors, like the one we've operated here in Durham for decades. Spanning that gap has opened up new opportunities."

The opportunity for Ryan and his SSC colleague Ulisse Bravar, UNH's principal investigator for the PAMELA mission, is to begin doing the detailed analysis of the May 17 data that will provide the scientific community with fresh insights.

UNH is funded for the PAMELA mission through the National Science Foundation's Solar, Heliospheric, and Interplanetary Environment (SHINE) program for the very purpose of analyzing data from these sorts of solar events because, notes Ryan, "this is an untapped capability of PAMELA. The NSF saw the value in getting this data and of having UNH, which has a strong history in , lead that effort."

Explore further: Curiosity brushes 'Bonanza king' target anticipating fourth red planet rock drilling

add to favorites email to friend print save as pdf

Related Stories

Moderate Labor Day solar flare eruption

Sep 07, 2011

At 9:35 PM ET on September 5, 2011, the sun emitted an Earth-directed M5.3 class flare as measured by the GOES satellite. The flare erupted from a region of the sun that appears close to dead center from Earth's ...

Sun delivered curveball of powerful radiation at Earth

Feb 01, 2012

A potent follow-up solar flare, which occurred Friday (Jan. 17, 2012), just days after the Sun launched the biggest coronal mass ejection (CME) seen in nearly a decade, delivered a powerful radiation punch ...

A 360 degree view of an X-class flare and a CME

Nov 08, 2011

(PhysOrg.com) -- The sun sent out two different kinds of solar activity last night in different directions. One was an X 1.9 class flare that burst out from an active region on the sun, numbered AR1339, which ...

NASA sees the sun having a solar blast (w/ video)

Jun 07, 2011

The Sun unleashed an M-2 (medium-sized) solar flare, an S1-class (minor) radiation storm and a spectacular coronal mass ejection (CME) on June 7, 2011 from sunspot complex 1226-1227. The large cloud of particles ...

An X1.4 Solar Flare and a CME

Sep 23, 2011

(PhysOrg.com) -- A large coronal mass ejection (CME) shot off the West (right) side of the sun at 6:24 PM ET on September 21, 2011. The CME is moving away from Earth at about 900 miles per second.

2012: Killer solar flares are a physical impossibility

Nov 11, 2011

(PhysOrg.com) -- Given a legitimate need to protect Earth from the most intense forms of space weather – great bursts of electromagnetic energy and particles that can sometimes stream from the sun – ...

Recommended for you

Australian amateur Terry Lovejoy discovers new comet

13 hours ago

It's confirmed! Australian amateur astronomer Terry Lovejoy just discovered his fifth comet, C/2014 Q2 (Lovejoy). He found it August 17th using a Celestron C8 fitted with a CCD camera at his roll-off roof ...

Students see world from station crew's point of view

Aug 19, 2014

NASA is helping students examine their home planet from space without ever leaving the ground, giving them a global perspective by going beyond a map attached to a sphere on a pedestal. The Sally Ride Earth ...

Mars deep down

Aug 19, 2014

Scarring the southern highlands of Mars is one of the Solar System's largest impact basins: Hellas, with a diameter of 2300 km and a depth of over 7 km.

User comments : 0