Featured Research

from universities, journals, and other organizations

We're not likely to get fried bygamma ray burst

Date:
December 10, 2013
Source:
University of Alabama Huntsville
Summary:
If recent news that researchers observed the largest gamma ray burst ever has you nervous about getting blasted into extinction, the researchers themselves say chances of that are exceedingly rare.

If recent news that University of Alabama in Huntsville (UAH) researchers observed the largest gamma ray burst ever has you nervous about getting blasted into extinction by a massive burst from space, the UAH researchers have good news.

The chances of Earth being fried by a burst are exceedingly rare. In fact, say Dr. Rob Preece, doctoral candidate J. Michael Burgess and Dr. Michael S. Briggs, Earth was actually at the center of the hit from April's big gamma ray burst, --which they picked up on equipment aboard the Fermi Space Telescope that UAH and partners NASA/MSFC and the Max Planck Institute for Extraterrestrial Physics in Germany designed and tested.

Yes, we took a direct hit. But the collapsing star that created the burst was so far away that it was very weak when it reached us. Stars that collapse and produce these bursts are far away, the researchers say, in older portions of the universe that were created early after the Big Bang event, portions where there are a lot of lighter elements that were flung far. Closer to Earth, there are a lot of heavier elements that suppress the collapse of stars.

"Our observations show that gamma ray bursts are less common in the immediate universe," said Dr. Briggs.

"These bursts occur in younger galaxies," said Burgess. "We're in the oldest galaxy in our immediate universe because as you look deeper into space you are looking back into time."

So any burst generated out there will come from really far away where we can detect it early, and it will be a comparative pipsqueak by the time it gets here.

"As I was thinking about it, I realized that we would have ample warning," Dr. Preece said. The stars involved are huge. "They blow off winds that we can see well in advance. We would know ahead of time if one of these guys was ready to go off."

The gamma ray burst created in these events is much more like a rifle than a shotgun. Unless you are close by and directly in the path, you're good. In fact, researchers are watching a star that's closer to Earth called Eta Carinae that's what they call a hyper-giant, ready to potentially collapse and release a gamma ray burst.

"But it would have to be pointed at us within 5 degrees of accuracy to do damage," Dr. Preece said. And while these events are regular across the universe, they only happen "once per million years per galaxy."

When a star collapses, it creates a phenomenon that looks like you've stuck your Dunkin Donuts coffee stirrer through the hole in your doughnut. The doughnut's center is a black hole, about which not much is known. The stirrer represents an incredibly powerful energy stream that scientists think is generated by the collapse -- the gamma ray burst.

The beauty part

OK, now that we have been reassured about calamity, here's the beauty part: the research. The big burst was icing on the cake for the UAH scientists, who detected it as they were testing out some very complex mathematical models against real data they were collecting from 14 sensors mounted on the Fermi Large Space Telescope.

Dr. Preece is primary author and Burgess secondary author of their research, "The First Pulse of the Extremely Bright GRB 130427A: A Test Lab for Synchrotron Shocks" in a recent issue of the journal Science. They had already done tests on other gamma ray bursts and were in the right place at the right time to witness the largest one ever recorded.

One reason the events leading to the origin and evolution of gamma ray bursts interest scientists is because they have many similarities to events that happened at the Big Bang. Understanding the phenomena could provide clues to the origins of the universe.

"We don't really know what is producing these gamma rays," said Burgess. "We think we know, and we think that it's because of a collapsing star."

Dr. Preece and Burgess have developed methods to measure the gamma ray spectra that may give insights into the origin of the bursts, called a jet by researchers. Instead of using theoretical constructs to test the methods, the UAH researchers are applying them to real world data from the Fermi telescope. The new methods are central to Burgess' doctoral thesis.

"For two years, we measured various bursts," Burgess said. "Then this burst happened and it was just perfect for what we needed to study." They've found that the models work surprisingly well and do provide insights into how gamma ray bursts work.

"We're trying to show how they are created, and from how they are created it gives us a window on where they were created within the jet," said Burgess. "These are the most awesomely energetic things that are happening in our universe since the Big Bang."

The equipment

None of that real-world testing would have been possible except for eight years of design and testing of the 12 low-energy sensors and two high-energy sensors that are aboard Fermi. UAH developed performance requirements and the Germans, with their subcontractors, did the detailed design work and built the detectors. Dr. Preece and Dr. Briggs developed the ground and flight software.

"NASA wanted a gamma ray instrument and we are experts in gamma rays, so we proposed it," said Dr. Briggs, who is the UAH principle investigator for the Fermi Gamma Ray Burst Monitor (GBM), the official name of the equipment UAH, NASA and the Germans created to fly on the Fermi telescope.

From 2000 to the flight in 2008, UAH, NASA and Marshall Space Flight Center worked in partnership with the German institute and German companies to document, build and test GBM. A U.S. company, Southwest Research Institute, designed and built the flight computer.

Dr. Briggs and Dr. Preece were both deeply involved in the testing of the monitor system at locations from Huntsville to Phoenix to the District of Columbia, and in its integration into the Fermi telescope, to the point where Dr. Preece oversaw technicians as they plugged in the wiring. UAH scientists gather at Cramer Hall weekly to teleconference with German researchers, who have the same computer equipment and software there.


Story Source:

The above story is based on materials provided by University of Alabama Huntsville. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. Ackermann et al. Fermi-LAT Observations of the Gamma-Ray Burst GRB 130427A. Science, 2013; DOI: 10.1126/science.1242353

Cite This Page:

University of Alabama Huntsville. "We're not likely to get fried bygamma ray burst." ScienceDaily. ScienceDaily, 10 December 2013. <www.sciencedaily.com/releases/2013/12/131210152537.htm>.
University of Alabama Huntsville. (2013, December 10). We're not likely to get fried bygamma ray burst. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2013/12/131210152537.htm
University of Alabama Huntsville. "We're not likely to get fried bygamma ray burst." ScienceDaily. www.sciencedaily.com/releases/2013/12/131210152537.htm (accessed September 16, 2014).

Share This



More Space & Time News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NASA’s Curiosity Rover Finally Reaches Long-Term Goal

NASA’s Curiosity Rover Finally Reaches Long-Term Goal

Newsy (Sep. 15, 2014) — After more than two years, NASA’s Mars Curiosity Rover reached Mount Sharp, its long-term destination. Video provided by Newsy
Powered by NewsLook.com
SpaceX's Elon Musk Really Wants To Colonize Mars

SpaceX's Elon Musk Really Wants To Colonize Mars

Newsy (Sep. 14, 2014) — Elon Musk has been talking about his goal of colonizing Mars for years now, but how much of it does he actually have figured out, and is it possible? Video provided by Newsy
Powered by NewsLook.com
International Space Station Crew Returns Safely To Earth

International Space Station Crew Returns Safely To Earth

Newsy (Sep. 11, 2014) — The three-man crew touched down in Kazakhstan Wednesday after more than five months of science experiments in orbit. Video provided by Newsy
Powered by NewsLook.com
Solar Storm To Hit This Weekend, Scientists Not Worried

Solar Storm To Hit This Weekend, Scientists Not Worried

Newsy (Sep. 11, 2014) — Two solar flares which erupted in our direction this week will arrive this weekend. The resulting solar storm will be powerful but not dangerous. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins