For milcom monitors in the Empire State -- Vigilant Guard will begin November 1!
Vigilant Guard is an annual joint civilian and military response exercise which allows civilian and military first-responders to practice life-saving skills.
The scenario this year is a national earthquake and the week-long exercise will be held at the Spaulding Fiber Plant in Tonawanda, NY November 1-6.
It gets a bit hectic, so it will not be open directly to the public but civilian media are invited and encouraged to come.
More details at http://www.dmna.state.ny.us/blog/journal.php?journal=1254502561
Thursday, October 29, 2009
Tuesday, October 27, 2009
10.7-cm flux - highest yet in current Sunspot Cycle 24
It just keeps getting better! During the CQ WW Contest weekend, the solar flux climbed into the upper 70's. But, as this week unfolds, the flux climbs, with a current flux of 81! This is the highest recording yet since the first observed "new cycle sunspot" in January 2008, the "official" visual start of Sunspot Cycle 24. (We'll see where the statistical averaged solar minimum actually occurs).
Speaking of... the monthly observed smoothed count of zero, recorded in August, does not make that the statistical lowest point in the moving average, because the months prior, and the months since, have higher numbers. And, these numbers, except for August, are all increasing, each month. The current sunspot activity is further confirmation that this cycle is, albeit slow, alive and increasing in activity.
DX was great over the weekend. Even 15 meters was hot with activity. This week is one to enjoy - the CME and Flare activity continues to be low to at most moderate, leaving the geomagnetic field mostly stable. This results in fairly normal (non-depressed) ionospheric conditions.
Please feel free to post your observations of conditions on HF, this week. It would be very enlightening to hear how conditions really are, in your location. Please post your grid square / location, along with the report of working conditions and results of your activity.
This is an exciting start to the Autumn DX season!
--
73 de NW7US, Tomas David Hood - Bitterroot Valley of Montana
Singer/Songwriter/Guitarist : http://tomasdavidhood.com
Contributing editor: CQ Magazine, CQ VHF, Popular Communications, Monitoring Times magazine
Pentagon Radio Volunteers Move to New Office
Gary Sessums, left, Navy Capt. Rick Low and John Grimes discuss communications capabilities at the new Military Affiliate Radio System office in the Pentagon, Oct. 21, 2009. DoD photo by Sally SobseyBy Jim Garamone, American Forces Press Service
WASHINGTON - A military institution designed to provide emergency communications has moved to new quarters in the Pentagon.
John G. Grimes, the former assistant secretary of defense for networks and information integration, cut the ribbon on the new Military Affiliate Radio System (AAN3PNT-LVH) office on the fifth floor of the Pentagon on October 21.
The facility is packed with shortwave radios, radio-telephone patches, computers and data links. It is manned by the Pentagon Amateur Radio Club. "This is a great facility, manned totally by volunteers," Grimes said. "It's a crucial capability for our country."
The system - known by the acronym MARS - began in the early 1950s. It was a worldwide network of shortwave radio enthusiasts who would spring into action in the event of a nuclear war or natural disaster. Thousands of civilian and military ham radio volunteers manned the system.
"In the years before the Internet, deployed servicemembers kept in touch with families and friends using MARS," said Gary Sessums, a contractor in the Pentagon and one of the stalwarts of the radio club.
From the Korean War to the Gulf War, soldiers, sailors, airmen and Marines used "Marsgrams" to keep in touch. Ham radio operators called these "health and welfare" messages.
The shortwave broadcasts have been superseded by the Internet, and servicemembers in many parts of the U.S. Central Command area can use cell phones and voice over Internet protocol to speak with those back home. Still, in the event of an emergency, high-frequency communication is generally the first to recover, and even the most modern technology can get overloaded.
Allan Hubbert, a volunteer in the Pentagon, noted communication problems during President Barack Obama's Jan. 20 inauguration as an example. "During the inauguration, there were so many people on cell phones that it overloaded the system," he said. "We could still operate, and helped back up the system down on the [National] Mall."
More than 60 volunteers help to man the Pentagon node of the system. They will turn out in force to help with communications for the Marine Corps Marathon, which will be held in the area this weekend. "In that case, we can help act as a bridge between the military and various local and regional agencies," said Navy Capt. Rich Low.
With more than 6,000 volunteers worldwide, the system now also backs up the Department of Homeland Security. "There have been many crises or disasters that have struck where the first word out of an area is via [shortwave radio], and someone has their little gas generator going," Grimes said. "That's not likely to change any time soon."
You can learn more about this new Pentagon Radio Station (Amateur and MARS) on the PARC website at http://www.k4af.org/.
A volunteer mans his radio at the new Military Affiliate Radio System in the Pentagon, Oct. 21, 2009. DoD photo by Sally Sobsey
Monday, October 26, 2009
Best Solar Prop Shop on the Net
If you are looking for the latest and greatest propagation and solar information I highly recommend the Solarcycle24.com website. VE3EN has put together some of the best web solar and propagation information sources onto one webpage for use by the radio hobby community.
If you are involved in the radio hobby and are advanced enough to know, use and understand how propagation works, then this site is a must visit and bookmark. I use it everyday. Go to http://www.solarcycle24.com/.
Global Tuner Node Operator Lost in Ham Aircraft Crash
Just an additional note to our earlier story on this blog regarding the four hams who passed away in the South Carolina plane crash enroute C6APR and the CQWW contest operation (4 Hams En Route to Contest Station Killed inPlane Crash
Randy Hargenrader, K4QO, was the operator of the Charleston SC receiver nodes on the popular Global Tuners (http://www.globaltuners.com/) website. He was one of the four hams who died last week in that tragic private aircraft crash. They were going to their ham radio contest station C6APR in the Bahamas with 3 other hams. His plane, a twin-engine, six-seat Piper Aztec — burst into flames after it crashed into a densely-wooded area shortly after taking off from Runway 24 in Dorchester County SC.
Randy Hargenrader, K4QO, was the operator of the Charleston SC receiver nodes on the popular Global Tuners (http://www.globaltuners.com/) website. He was one of the four hams who died last week in that tragic private aircraft crash. They were going to their ham radio contest station C6APR in the Bahamas with 3 other hams. His plane, a twin-engine, six-seat Piper Aztec — burst into flames after it crashed into a densely-wooded area shortly after taking off from Runway 24 in Dorchester County SC.
Veterans Day Special Event Station K0V
The Emporia Amateur Radio Society will be on the air with a special event station on November 7th and on Veterans Day, November 11, to honor our Veterans. We will be using the special event callsign KØV, and the station will be located adjacent to the Emporia All Veterans Memorial. You can get more information at:
http://www.qsl.net/emporiaars/Veterans%20Day%20Special%20Event%20Station.html
Friday, October 23, 2009
VK9 Callsign Changes
VK9 C, L, M, N, W & X deleted from DX equation
The Australian Communications and Media Authority (ACMA) has decided to discontinue the use of a VK9 callsign suffix letter to denote each of the six Australian external territories, each a DX entity.
The long-standing prefixes included VK9C for Cocos (Keeling) Island, VK9L Lord Howe Island, VK9M Mellish Reef, VK9N Norfolk Island, VK9W Willis Island and VK9X Christmas Island.
The Wireless Institute of Australia (WIA), under its role of providing ham radio licence examinations and issuing amateur certificates of proficiency, also recommends each and every amateur radio callsign issued by the ACMA.
On taking on new roles earlier this year it began to query the practices in relation to VK9 callsigns, then consulted the amateur radio community and came to the view that it could not support having a suffix letter as a geographic identifier in VK9 callsigns.
The ACMA itself has not stuck with the VK9 callsign tradition over the years when issuing licences and some DXers requested a callsign contrary to the historic or DXCC list suffix block.
VK9Y has also been used for Cocos and VK9Z for Mellish, and often, particularly recently, if a VK9 callsign was requested it would be issued.
The ACMA having not rigidly applied its own VK9 callsign policy, and wanting to eliminate where-ever possible administrative tasks related to the amateur radio service, decided that the historic VK9 callsigns are a thing of the past.
From 1 November, callsigns for the VK9 DX entities will fall in line with the practice for issuing callsigns for all other VK call areas, with the suffix only to denoting the class of licence issued - Advanced, Standard or Foundation.
Licences with a VK9 callsign issued to visiting overseas radio amateurs will only be for a short-term if requested or for a maximum 12 months period, and not be automatically renewed.
A VK ham or visiting radio amateur does not necessarily require a VK9 callsign, although most do for DXing, contesting or QSLing purposes.
Under the provisions of the Amateur Licence Conditions Determination, portable operation is permitted with a radio amateur using their home callsign /VK9 and stating their location.
Jim Linton VK3PC
The Australian Communications and Media Authority (ACMA) has decided to discontinue the use of a VK9 callsign suffix letter to denote each of the six Australian external territories, each a DX entity.
The long-standing prefixes included VK9C for Cocos (Keeling) Island, VK9L Lord Howe Island, VK9M Mellish Reef, VK9N Norfolk Island, VK9W Willis Island and VK9X Christmas Island.
The Wireless Institute of Australia (WIA), under its role of providing ham radio licence examinations and issuing amateur certificates of proficiency, also recommends each and every amateur radio callsign issued by the ACMA.
On taking on new roles earlier this year it began to query the practices in relation to VK9 callsigns, then consulted the amateur radio community and came to the view that it could not support having a suffix letter as a geographic identifier in VK9 callsigns.
The ACMA itself has not stuck with the VK9 callsign tradition over the years when issuing licences and some DXers requested a callsign contrary to the historic or DXCC list suffix block.
VK9Y has also been used for Cocos and VK9Z for Mellish, and often, particularly recently, if a VK9 callsign was requested it would be issued.
The ACMA having not rigidly applied its own VK9 callsign policy, and wanting to eliminate where-ever possible administrative tasks related to the amateur radio service, decided that the historic VK9 callsigns are a thing of the past.
From 1 November, callsigns for the VK9 DX entities will fall in line with the practice for issuing callsigns for all other VK call areas, with the suffix only to denoting the class of licence issued - Advanced, Standard or Foundation.
Licences with a VK9 callsign issued to visiting overseas radio amateurs will only be for a short-term if requested or for a maximum 12 months period, and not be automatically renewed.
A VK ham or visiting radio amateur does not necessarily require a VK9 callsign, although most do for DXing, contesting or QSLing purposes.
Under the provisions of the Amateur Licence Conditions Determination, portable operation is permitted with a radio amateur using their home callsign /VK9 and stating their location.
Jim Linton VK3PC
Thursday, October 22, 2009
4 Hams En Route to Contest Station Killed inPlane Crash
Tragic late breaking news from the CQ/WorldRadio Online Newsroom...
Four well-known contesters en route to operate the CQ World Wide DX Contest this weekend from Bahamas were killed yesterday when their plane crashed shortly after takeoff from South Carolina. The four, all regular operators of the C6APR contest station, were identified as Peter Radding, W2GJ/C6APR, the pilot; and passengers Ed Steeble, K3IXD/C6AXD; Randy Hargenrader, K4QO/C6AQO, and Dallas Carter, W3PP.
According to the local Summerville Journal Scene newspaper, the plane crashed 250 yards east of the runway at Summerville Airport in Jedburg, South Carolina. The cause of the crash has not yet been determined, but Radding was a very experienced pilot. County Coroner Chris Nesbit told the newspaper that it appears the four were killed by the severity of the crash itself rather than the fire that followed. Autopsies are scheduled for today.
CQ WW Contest Director Bob Cox, K3EST, called the crash, "a real tragedy," adding that "devoted hams and contesters were lost." The C6APR team was featured in the cover story of April's WorldRadio Online, and Steeble wrote an article in the April, 2007 issue of CQ about his experiences as QSL manager for C6APR and for a special Islands on the Air expedition, W2GJ/C6A, in 2006. As of this morning, comments from hams around the world had been posted on the Journal Scene's website.
Additional details on this story available on the ARRL website at
http://www.arrl.org/news/stories/2009/10/21/11157/?nc=1
This is a tremendous loss to the amateur radio community and our heartfelt prayers and condolences go out to Peter, Ed, Randy and Dallas' families who were lost in the crash.
Four well-known contesters en route to operate the CQ World Wide DX Contest this weekend from Bahamas were killed yesterday when their plane crashed shortly after takeoff from South Carolina. The four, all regular operators of the C6APR contest station, were identified as Peter Radding, W2GJ/C6APR, the pilot; and passengers Ed Steeble, K3IXD/C6AXD; Randy Hargenrader, K4QO/C6AQO, and Dallas Carter, W3PP.
According to the local Summerville Journal Scene newspaper, the plane crashed 250 yards east of the runway at Summerville Airport in Jedburg, South Carolina. The cause of the crash has not yet been determined, but Radding was a very experienced pilot. County Coroner Chris Nesbit told the newspaper that it appears the four were killed by the severity of the crash itself rather than the fire that followed. Autopsies are scheduled for today.
CQ WW Contest Director Bob Cox, K3EST, called the crash, "a real tragedy," adding that "devoted hams and contesters were lost." The C6APR team was featured in the cover story of April's WorldRadio Online, and Steeble wrote an article in the April, 2007 issue of CQ about his experiences as QSL manager for C6APR and for a special Islands on the Air expedition, W2GJ/C6A, in 2006. As of this morning, comments from hams around the world had been posted on the Journal Scene's website.
Additional details on this story available on the ARRL website at
http://www.arrl.org/news/stories/2009/10/21/11157/?nc=1
This is a tremendous loss to the amateur radio community and our heartfelt prayers and condolences go out to Peter, Ed, Randy and Dallas' families who were lost in the crash.
Wednesday, October 21, 2009
Comments Sought for Draft Channel Naming Standards
Here is the APCO pdf document with a complete list of interop freqs and the proposed new desigs. This is a must download for active public safety scanner monitors.
http://apcointl.org/new/commcenter911/documents/APCO-NPSTC-ANS-1-104-1DraftPRC.pdf
APCO NPSTC
2009 Oct 20
Alexandria, Va. - The Association of Public-Safety Communications Officials (APCO) International and the National Public Safety Telecommunications Council (NPSTC) released for comments a candidate American National Standard (ANS) to ensure national consistency of interoperability on related radio channels. The proposed Standard Channel Nomenclature for Public Safety Interoperability Channels provides a standardized naming format for each Federal Communications Commission (FCC) designated Interoperability Channel in Public Safety Radio Services.
“The public safety community uses 700 MHz spectrum allocated by the FCC that is replete with interoperability channels,” APCO International Executive Director George Rice said. “It is necessary to develop and employ a common set of channel names. It is crucial that all responders to an incident know which channel to tune their radios to, as well as the band and primary use for the channel.”
NPSTC Chair Ralph A. Haller said that he was pleased to see such a positive step forward in interoperability saying, “Common interoperability channel names will help to assure that any organization responding to an emergency will be able to establish contact immediately when arriving on scene. Although the specific channel names were initially controversial, the proposed standard represents the collective efforts of public safety agencies across the country to reach consensus. NPSTC is pleased to have been instrumental in this process."
The issue of common channel naming has been on the forefront since the mid-1980s and was again highlighted during the terrorist attacks on September 11, 2001 and Hurricane Katrina. In 2006, NPSTC reviewed and updated the Standard Channel Nomenclature recommended in the 700 MHz National Coordination Committee’s Final Report. This new protocol has been widely adopted across the country in the intervening period, and requests to the federal government resulted in finalizing standard names for similar channels in federal agency spectrum earlier this year.
APCO International is the recognized American National Standards Institute (ANSI)-accredited Standards Developer for public safety communications standards and was selected to facilitate the most recent version of the Standard Channel Nomenclature document through the ANSI standardization process, moving one step closer to completion of National Emergency Communications Plan milestone 3.1.33.
There is a 45-day public review and comment period for this standard that ends on November 30. The Candidate ANS can be downloaded at http://apcointl.org/new/commcenter911/ansi-activity.php . To submit comments or questions prior to the deadline, e-mail standards@apco911.org .
http://apcointl.org/new/commcenter911/documents/APCO-NPSTC-ANS-1-104-1DraftPRC.pdf
APCO NPSTC
2009 Oct 20
Alexandria, Va. - The Association of Public-Safety Communications Officials (APCO) International and the National Public Safety Telecommunications Council (NPSTC) released for comments a candidate American National Standard (ANS) to ensure national consistency of interoperability on related radio channels. The proposed Standard Channel Nomenclature for Public Safety Interoperability Channels provides a standardized naming format for each Federal Communications Commission (FCC) designated Interoperability Channel in Public Safety Radio Services.
“The public safety community uses 700 MHz spectrum allocated by the FCC that is replete with interoperability channels,” APCO International Executive Director George Rice said. “It is necessary to develop and employ a common set of channel names. It is crucial that all responders to an incident know which channel to tune their radios to, as well as the band and primary use for the channel.”
NPSTC Chair Ralph A. Haller said that he was pleased to see such a positive step forward in interoperability saying, “Common interoperability channel names will help to assure that any organization responding to an emergency will be able to establish contact immediately when arriving on scene. Although the specific channel names were initially controversial, the proposed standard represents the collective efforts of public safety agencies across the country to reach consensus. NPSTC is pleased to have been instrumental in this process."
The issue of common channel naming has been on the forefront since the mid-1980s and was again highlighted during the terrorist attacks on September 11, 2001 and Hurricane Katrina. In 2006, NPSTC reviewed and updated the Standard Channel Nomenclature recommended in the 700 MHz National Coordination Committee’s Final Report. This new protocol has been widely adopted across the country in the intervening period, and requests to the federal government resulted in finalizing standard names for similar channels in federal agency spectrum earlier this year.
APCO International is the recognized American National Standards Institute (ANSI)-accredited Standards Developer for public safety communications standards and was selected to facilitate the most recent version of the Standard Channel Nomenclature document through the ANSI standardization process, moving one step closer to completion of National Emergency Communications Plan milestone 3.1.33.
There is a 45-day public review and comment period for this standard that ends on November 30. The Candidate ANS can be downloaded at http://apcointl.org/new/commcenter911/ansi-activity.php . To submit comments or questions prior to the deadline, e-mail standards@apco911.org .
Monday, October 19, 2009
SAQ October Transmissions Cancelled
Grimeton Radio/SAQ transmission CW on VLF 17.2 kHz
We deeply regret we have to cancel the previously announced transmission on United Nations Day, October 24th 2009. Next planned transmission will be on Christmas Eve, December 24th 2009, at 08:00 UTC.
Lars, SM6NM
Wednesday, October 14, 2009
NASA retires 'queen' of tracking satellite fleet
Article by STEPHEN CLARK on SPACEFLIGHT NOW
More than a quarter-century after a hard-luck launch aboard the shuttle Challenger, the pioneer of NASA's constellation of tracking and communications satellites is being retired from service.
Named TDRS 1, the satellite's last traveling wave tube amplifier recently failed, rendering the craft unable to support most of its users' Ku-band data relay and telemetry needs, according to Roger Flaherty, the Space Network project manager at NASA's Goddard Space Flight Center in Maryland.
"We are going to relocate TDRS 1 and that relocation process will start on or about the 21st of October," Flaherty said.
TDRS 1 is currently located in a geosynchronous orbit more than 22,000 miles above Earth. At that altitude, satellites' orbits match the speed of Earth's rotation, causing spacecraft to hover over a specific geographic region.
Now positioned at 49 degrees west longitude, TDRS 1 will soon be moved to a nearby temporary slot for final decommissioning activities, according to NASA.
Read the rest of the whole copyrighted story at http://www.spaceflightnow.com/news/n0910/13tdrs/
More than a quarter-century after a hard-luck launch aboard the shuttle Challenger, the pioneer of NASA's constellation of tracking and communications satellites is being retired from service.
Named TDRS 1, the satellite's last traveling wave tube amplifier recently failed, rendering the craft unable to support most of its users' Ku-band data relay and telemetry needs, according to Roger Flaherty, the Space Network project manager at NASA's Goddard Space Flight Center in Maryland.
"We are going to relocate TDRS 1 and that relocation process will start on or about the 21st of October," Flaherty said.
TDRS 1 is currently located in a geosynchronous orbit more than 22,000 miles above Earth. At that altitude, satellites' orbits match the speed of Earth's rotation, causing spacecraft to hover over a specific geographic region.
Now positioned at 49 degrees west longitude, TDRS 1 will soon be moved to a nearby temporary slot for final decommissioning activities, according to NASA.
Read the rest of the whole copyrighted story at http://www.spaceflightnow.com/news/n0910/13tdrs/
Saturday, October 03, 2009
Yellowstone National Park Freqs
Here is a list of Yellowstone National Park freqs courtesy of Peter Sz
North District
166.3750/166.9750 Henderson repeater (192.8 Hz pl tone) (Lamar District)
166.3250/166.9350 Washburn repeater (167.9 Hz pl tone)
166.3750 Lamar direct (simplex)(192.8 Hz pl tone) (Lamar District)
166.3250 Washburn direct (simplex) (167.9 Hz pl tone)
South District
165.5875/164.8000 Sheridan repeater (110.9 Hz pl tone)
165.5875/164.8000 Top Notch repeater (118.8 Hz pl tone)
165.5875/164.8000 Bechler repeater (127.3 Hz pl tone)
165.5875 South Direct (simplex) (110.9 Hz pl tone)
West District
166.8750/169.4000 West repeater (136.5 Hz pl tone)
166.8750/169.4000 Holmes repeater (146.2 Hz pl tone)
166.8500 West Direct (simplex) (136.5 Hz pl tone)
Parkwide Freqs
167.1500/163.1250 SOA (Portable) repeaters (SOA 1 206.5 Hz pl tone, SOA 2 218.1 Hz pl tone, SOA 3 229.1 Hz pl tone)
168.6125 NPS Common (136.5 Hz pl tone)
172.5000 Fire Cache (wildfire) (103.5 Hz pl tone)
163.100 Usage unknown, maybe MTNCE
168.350 Usage unknown, maybe MTNCE
North District
166.3750/166.9750 Henderson repeater (192.8 Hz pl tone) (Lamar District)
166.3250/166.9350 Washburn repeater (167.9 Hz pl tone)
166.3750 Lamar direct (simplex)(192.8 Hz pl tone) (Lamar District)
166.3250 Washburn direct (simplex) (167.9 Hz pl tone)
South District
165.5875/164.8000 Sheridan repeater (110.9 Hz pl tone)
165.5875/164.8000 Top Notch repeater (118.8 Hz pl tone)
165.5875/164.8000 Bechler repeater (127.3 Hz pl tone)
165.5875 South Direct (simplex) (110.9 Hz pl tone)
West District
166.8750/169.4000 West repeater (136.5 Hz pl tone)
166.8750/169.4000 Holmes repeater (146.2 Hz pl tone)
166.8500 West Direct (simplex) (136.5 Hz pl tone)
Parkwide Freqs
167.1500/163.1250 SOA (Portable) repeaters (SOA 1 206.5 Hz pl tone, SOA 2 218.1 Hz pl tone, SOA 3 229.1 Hz pl tone)
168.6125 NPS Common (136.5 Hz pl tone)
172.5000 Fire Cache (wildfire) (103.5 Hz pl tone)
163.100 Usage unknown, maybe MTNCE
168.350 Usage unknown, maybe MTNCE
Chicago Area Federal Freqs from CARMA list
Here are some Chicago IL area federal freqs courtesy of the CARMA list. If you have some freqs to share, please pass them along to the email address in the masthead and I will post them up here or if they are military to my Milcom blog. You can remain anonymous if you so desire, just let me know your wishes.
162.7875 P25 U.S. MARSHALS (encryped most times but some clear)
162.9000 P25 Unknown
163.4750 P25 ICE OHARE
163.6250 P25 ICE OHARE
163.7500 P25 ICE OHARE
165.2875 P25 ATF NET 1
165.8500 P25 ICE OHARE
169.1625 P25 TSA OHARE
172.9000 P25 TSA OHARE
403.3375 P25 US POSTAL INSP
403.8375 P25 JB VA POLICE
406.7000 P25 DHS/FPS POLICE
409.5250 P25 U.S.STATE DEPT
411.3500 P25 HINES VA POLICE
Fermi Large Area Telescope Reveals Pulsing Gamma-Ray Sources
By Daniel Parry, Naval Research Laboratory, Public Affairs
WASHINGTON, D.C. (NNS) -- Scientists at the Naval Research Laboratory-Space Science Division and a team of international researchers have positively identified cosmic sources of gamma-ray emissions through the discovery of 16 pulsating neutron stars.
Using the Large Area Telescope (LAT), the primary instrument on NASA's Fermi Gamma-ray Space Telescope satellite, the discoveries were made by conducting blind frequency searches on the sparse photon data provided by the LAT. The photons had energies between 20 Mega-electron-volts (MeVs) and 300 Giga-electron-volts (GeVs)— tens of millions to hundreds of billions of times more energetic than the photons we see with the human eye.
A second study, published at the same time, announced the detection of gamma-ray pulsations from eight Galactic millisecond pulsars (MSPs). Millisecond pulsars spin hundreds of times per second, but have magnetic fields 10,000 times lower than normal pulsars. These discoveries confirm that they, too, can produce powerful gamma-ray emissions.
"Fermi has truly unprecedented power for discovering and studying gamma ray pulsars," said Paul Ray, astrophysicist, Naval Research Laboratory. "Since the demise of the Compton Gamma Ray Observatory a decade ago, we've wondered about the nature of unidentified gamma-ray sources it detected in our galaxy. These studies from Fermi lift the veil on many of them."
Pulsars are rapidly rotating, highly magnetized neutron stars that can emit radiation across the electromagnetic spectrum. Prior to the launch of Fermi, gamma-ray pulsations were only detected from pulsars previously discovered using radio or X-ray telescopes. Radio telescopes can detect pulsars only if one of the narrow radio beams is directly aimed at the telescope; otherwise the pulsar can remain hidden. The much broader gamma-ray beams allowed the new pulsars to be discovered as part of a comprehensive search for periodic gamma-ray emission using five months of Fermi LAT data and new computational techniques.
The newly discovered pulsars, with rotation periods that range from 48 to 444 milliseconds, help reveal the geometry of emission from rotation-powered pulsars and provide valuable information on population statistics, the energetics of pulsar wind nebulae and supernova remnants. A wide variety of astrophysical phenomena, such as pulsars, active galactic nuclei, gamma-ray bursts and some binary star systems are known to produce photons exceeding many MeVs.
"The Fermi LAT makes it possible for us to pinpoint neutron stars," said Eric Grove, astrophysicist and LAT Commissioner, NRL Space Science Division. "The combination of a very large collecting area, large field of view, and precision timing from an on-board Global Positioning System receiver enables the LAT to see sources that were far beyond the reach of previous gamma-ray telescopes."
Results of the two studies: "Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT;" and "A population of gamma-ray millisecond pulsars seen with the Fermi Large Area Telescope" were published on July 2, 2009 in Science Express and may be found on the Internet at http://www.scienceexpress.org.
The LAT project is funded in the United States by NASA and developed in collaboration with the Department of Energy and by academic institutions and government agencies in France, Italy, Japan, and Sweden.
The Naval Research Laboratory is the Department of the Navy's corporate laboratory. NRL conducts a broad program of scientific research, technology, and advanced development. The Laboratory, with a total complement of nearly 2,500 personnel, is located in southwest Washington, DC, with other major sites at the Stennis Space Center, MS; and Monterey, CA.
WASHINGTON, D.C. (NNS) -- Scientists at the Naval Research Laboratory-Space Science Division and a team of international researchers have positively identified cosmic sources of gamma-ray emissions through the discovery of 16 pulsating neutron stars.
Using the Large Area Telescope (LAT), the primary instrument on NASA's Fermi Gamma-ray Space Telescope satellite, the discoveries were made by conducting blind frequency searches on the sparse photon data provided by the LAT. The photons had energies between 20 Mega-electron-volts (MeVs) and 300 Giga-electron-volts (GeVs)— tens of millions to hundreds of billions of times more energetic than the photons we see with the human eye.
A second study, published at the same time, announced the detection of gamma-ray pulsations from eight Galactic millisecond pulsars (MSPs). Millisecond pulsars spin hundreds of times per second, but have magnetic fields 10,000 times lower than normal pulsars. These discoveries confirm that they, too, can produce powerful gamma-ray emissions.
"Fermi has truly unprecedented power for discovering and studying gamma ray pulsars," said Paul Ray, astrophysicist, Naval Research Laboratory. "Since the demise of the Compton Gamma Ray Observatory a decade ago, we've wondered about the nature of unidentified gamma-ray sources it detected in our galaxy. These studies from Fermi lift the veil on many of them."
Pulsars are rapidly rotating, highly magnetized neutron stars that can emit radiation across the electromagnetic spectrum. Prior to the launch of Fermi, gamma-ray pulsations were only detected from pulsars previously discovered using radio or X-ray telescopes. Radio telescopes can detect pulsars only if one of the narrow radio beams is directly aimed at the telescope; otherwise the pulsar can remain hidden. The much broader gamma-ray beams allowed the new pulsars to be discovered as part of a comprehensive search for periodic gamma-ray emission using five months of Fermi LAT data and new computational techniques.
The newly discovered pulsars, with rotation periods that range from 48 to 444 milliseconds, help reveal the geometry of emission from rotation-powered pulsars and provide valuable information on population statistics, the energetics of pulsar wind nebulae and supernova remnants. A wide variety of astrophysical phenomena, such as pulsars, active galactic nuclei, gamma-ray bursts and some binary star systems are known to produce photons exceeding many MeVs.
"The Fermi LAT makes it possible for us to pinpoint neutron stars," said Eric Grove, astrophysicist and LAT Commissioner, NRL Space Science Division. "The combination of a very large collecting area, large field of view, and precision timing from an on-board Global Positioning System receiver enables the LAT to see sources that were far beyond the reach of previous gamma-ray telescopes."
Results of the two studies: "Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT;" and "A population of gamma-ray millisecond pulsars seen with the Fermi Large Area Telescope" were published on July 2, 2009 in Science Express and may be found on the Internet at http://www.scienceexpress.org.
The LAT project is funded in the United States by NASA and developed in collaboration with the Department of Energy and by academic institutions and government agencies in France, Italy, Japan, and Sweden.
The Naval Research Laboratory is the Department of the Navy's corporate laboratory. NRL conducts a broad program of scientific research, technology, and advanced development. The Laboratory, with a total complement of nearly 2,500 personnel, is located in southwest Washington, DC, with other major sites at the Stennis Space Center, MS; and Monterey, CA.
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