Our newest GOES-R and GOES-S weather satellites will greatly enhance search and rescue capabilities @NASAsocial

Readers may recall that last week I was the guest of NASA KSC to watch the launch of GOES-S, which is going to be a boon for mapping and alerting the west coast to severe weather, including lightning, wildfires, and atmospheric rivers. But, I’ll bet you didn’t know this: The same satellites that identify severe weather can help save you from it.

The National Oceanic and Atmospheric Administration’s (NOAA’s) Geostationary Operational Environmental Satellite (GOES) constellation monitors Earth’s environment, helping meteorologists observe and predict the weather. GOES observations have tracked thunderstorms, tornadoes, hurricanes and flash floods. They’ve even proven useful in monitoring dust storms, forest fires and volcanic activity.

The recently launched GOES-S (planned to replace the current GOES-West later this year) and other GOES series satellites carry a payload supported by NASA’s Search and Rescue (SAR) office, which researches and develops technologies to help first responders locate people in distress worldwide, whether from a plane crash, a boating accident or other emergencies.

Over its history, the SAR office at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, has developed emergency beacons for personal, nautical and aeronautical use, along with ground station receivers that detect beacon activation. Space segment SAR instruments fly on many spacecraft in various orbits around the Earth. The GOES SAR transponders are geostationary, meaning that they appear “fixed” relative to a user on the surface due to their location over the equator and orbital period of 24 hours.

“The SAR space segment isn’t just one instrument in one orbit,” said Tony Foster, SAR’s deputy mission manager. “Rather it’s a series of instruments aboard diverse satellites in various orbits, each working together to provide first responders with highly accurate locations.”

The GOES search and rescue transponders, unlike SAR instruments in other orbits, are only able to detect the beacon signals, not help to determine location. This detection rapidly alerts the global SAR network, Cospas-Sarsat, of a distress beacon’s activation. This gives the system valuable time to prepare before the signal’s origin can be determined by SAR instruments on low-Earth-orbiting satellites.

Additionally, beacons with integrated GPS technology can send their location data through GOES to the SAR network. The network can then alert local first responders to the location of the emergency without the aid of the low-Earth-orbiting constellation of search and rescue instruments.

NASA’s SAR team provides on-orbit testing, support and maintenance of the search and rescue instrument on GOES. The GOES satellites and SAR instruments are funded by NOAA.

“We are proud to support the Cospas-Sarsat program by hosting a search and rescue transponder aboard our satellites,” said Tim Walsh, GOES-R series program acting system program director. “SAR is one of the many NOAA-NASA collaborations that translate into life-saving technology.”

In the future, first responders will rely on a new constellation of instruments on GPS and other Global Navigation Satellite Systems currently in medium-Earth orbit, an orbit that views larger swathes of the Earth than low-Earth orbit due to higher altitudes. These new instruments will enable the SAR network to locate a distress signal more quickly than the current system and calculate their position with accuracy an order of magnitude better, from one kilometer (0.6 miles) to approximately 100 meters (328 feet).

NASA develops technologies that aid first responders in search and rescue efforts. CREDIT US Coast Guard photo by PAC Tom Sperduto

In the meantime, the SAR transponders aboard GOES cover the time between the activation of a distress signal and detection by SAR instruments in low-Earth orbit.

“NASA’s SAR office dedicates itself to speed and accuracy,” said Lisa Mazzuca, SAR mission manager. “The instruments and technologies we develop endeavor to alert first responders to a beacon’s activation as soon as possible. The GOES search and rescue transponders are crucial to this goal, providing near-instantaneous detection in the fields of view of the Earth.”


Story via NASA Goddard


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So what’s the advantage again? I read it, but didn’t understand any orders of magnitude better for improved forecasting.


“We will see”, said the blind China-man.

“The GOES search and rescue transponders, unlike SAR instruments in other orbits, are only able to detect the beacon signals, not help to determine location. This detection rapidly alerts the global SAR network, Cospas-Sarsat, of a distress beacon’s activation. This gives the system valuable time to prepare before the signal’s origin can be determined by SAR instruments on low-Earth-orbiting satellites.”
This is puzzling. There are normally at least four satellites visible from any location using GPS. I cannot remember how many satellites are equipped for the 243 MHz distress and safety system (I think all of them), but I think that several of the GMDSS (Global Maritime Distress and Safety System) satellites would be visible at any time. So the fact that the GOES weather satellite will also receive the 243 MHz signal would probably seem to be superfluous.
What is more, IIRC, the satellites do not calculate any position for a distress incident. What they do is relay the signal to one of the ground stations which, using the varying elapsed times when the signal is received from several satellites, and knowing the position of the satellites, can calculate the distance from each and hence the location on the surface of the earth.
Perhaps things have changed since I had anything to do with this?

The earliest distress and safety satellites used 121.5 mHz. They were low earth, is an orbit a bit more than 90 minutes. As they traversed the earth’s surface, in orbits more nearly polar than equatorial, they were able to provide the ground station with info regarding the doppler shift of the received signal, and so a single satellite was able to give an estimation of how far off track the distress signal was, and in which direction. This resulted in two positions, equidistant on either side of the satellite track. A second satellite be also giving two positions was able to give info as to which was the distress position – whichever position was the same for both satellites. Alternatively, the same satellite on a second pass, if the distress position was still visible from the satellite, would provide corroboration. Accuracy was or the order of 25 miles, which meant that surface ships and overflying aircraft could be advised and requested to keep watch when near this area. The beacons were cheap and virtually every yachtsman in the Australian SAR area had one. However, when the 423 mHz system became operational the (much larger and more expensive) beacons could transmit GPS coordinates, thus reducing the uncertainty to a fraction of a mile. After some time using both systems, the 121.5 MHz system was shut down.
MEMO to any yachtsman – if you are going to sail more than a few miles off the coast, ensure you have a GPS capable 423 MHz distress beacon. Also ensure that it is stowed so it will float free if your yacht capsizes, and preferably attached to the painter of one of your liferafts. No point in having it stowed in a drawer down below!


… 423 MHz …
Actually it’s 406 MHz.


Will also keep an eye on China…

Coeur de Lion

Did it use fossil fuels at all, do you think?

James Bull

To me it seems that they are finally getting to the stage of launching International Rescue as shown by Gerry and Silvia Anderson in Thunderbirds.
I would be late for Sunday lunch because I wanted to see the end of the show.
James Bull


Yeah, “super puppeteering” was super cool. Loved those shows made by a British company.

Sorry, this is nothing new. GOES has been in the Geostationary Orbiting Search And Rescue (GEOSAR) business for decades. The SARSAT transponder was modified slightly for the GOES-R Series to operate with a lower uplink power (32 dBm), enabling GOES-R Series satellites to detect weaker signal beacons.


We need to send up another high tech satellite that spots climate policy fraud building up in Sacramento and the Bay area.

Anthony ==> As you know, my wife and I lived aboard the Golden Dawn for 12 years in the Northern Caribbean. She is equipped with a NOAA-registered Emergency Position Indicating Radio Beacon (EPIRB). We never had occasion to use it, but were comforted that it was there in case.
We did respond to a US Coast Guard aircraft request to respond to a fishing vessel in the area between the Turks and Caicos and Hispaniola, which had activated its beacon.

We carried EPIRB on my sailboat Windsong, even though only sailing the Great Lakes Superior, Michigan, and Huron.

ristvan ==> ALWAYS better safe than sorry. Few people realize that the Great Lakes actually have hurricane force storms and sailing there can be just as dangerous as trans-oceanic blue water sailing.

Randy Bork

I was looking at some live data from GEOS-16 today [see loop at http://col.st/cjKXU%5D. That is showing quite a storm system over the Amazon area in Band 16, the Co2 IR band. Thinking about Willis Eschenbach’s writing relative to the surface cooling of the ocean along the equator I am now wondering if the cooling to space of storm systems could be quantified by data available from these satellites?

Randy Bork

The link above somehow gor %5D added it should just be http://col.st/cjKXU

Thanks Johanus, 406 MhZ is correct. Long time since I worked in that area!