Could Earthquake Sensors Help Detect Falling Space Junk? (msn.com) 13
An anonymous reader shared this report from the Washington Post:
Scientists have found that using seismometers is a new and inexpensive method to detect falling space junk, which can cause damage on impact and carry toxic materials — and may someday turn deadly...
It's not an easy task to track large hunks of falling metal everywhere in the world. Ground-based radar can detect falling objects, but it doesn't cover much of the world or is often classified data, said Ben Fernando [a planetary scientist at Johns Hopkins University who is leading this research]. The other option is through optical instruments, such as doorbell cameras, but the information on the time, size and speed can be limited. Instead, Fernando turned to seismology data. Stations located around the world live-stream data, which can be easily downloaded. Seismometers have been used to track meteors in the sky for over a century, but he said this is the first time he's aware of its use for tracking space debris.
Stations located around the world live-stream data, which can be easily downloaded. Seismometers have been used to track meteors in the sky for over a century, but he said this is the first time he's aware of its use for tracking space debris. Fernando first tested the idea to track the controlled reentry of NASA's OSIRIS-REx mission in September 2023, which brought back material from the asteroid Bennu. He set up seismometers along the capsule's path in the landing spot in Utah and measured its sonic boom. "It's a really good way of monitoring what's coming in, how often it's coming in, how big the things hitting the Earth are," said Fernando, who presented his results at the American Geophysical Union conference in December...
"The shockwave deforms the ground around the seismometer," said Fernando. "It also keeps ringing for a lot longer because all of that energy is bouncing around in the soil...." [H]e said an automated system could help detect these objects within moments of it appearing on the stations. In addition to detecting an event, the seismometers can help locate where any debris may have fallen. Tracking debris is important because some space debris can contain toxic materials that can harm the surrounding environment.
The article notes reports of the uncontrolled reentry into Earth's atmosphere of at least 951 objects larger than one square meter from 2010 to 2022.
"On average, objects heavier than 1,000 pounds came down about every 8 days... In fact, the threat of getting hit by uncontrolled orbital reentries has increased by a factor of four from 2010 to 2023, said Luciano Anselmo, who published a study assessing the risk."
It's not an easy task to track large hunks of falling metal everywhere in the world. Ground-based radar can detect falling objects, but it doesn't cover much of the world or is often classified data, said Ben Fernando [a planetary scientist at Johns Hopkins University who is leading this research]. The other option is through optical instruments, such as doorbell cameras, but the information on the time, size and speed can be limited. Instead, Fernando turned to seismology data. Stations located around the world live-stream data, which can be easily downloaded. Seismometers have been used to track meteors in the sky for over a century, but he said this is the first time he's aware of its use for tracking space debris.
Stations located around the world live-stream data, which can be easily downloaded. Seismometers have been used to track meteors in the sky for over a century, but he said this is the first time he's aware of its use for tracking space debris. Fernando first tested the idea to track the controlled reentry of NASA's OSIRIS-REx mission in September 2023, which brought back material from the asteroid Bennu. He set up seismometers along the capsule's path in the landing spot in Utah and measured its sonic boom. "It's a really good way of monitoring what's coming in, how often it's coming in, how big the things hitting the Earth are," said Fernando, who presented his results at the American Geophysical Union conference in December...
"The shockwave deforms the ground around the seismometer," said Fernando. "It also keeps ringing for a lot longer because all of that energy is bouncing around in the soil...." [H]e said an automated system could help detect these objects within moments of it appearing on the stations. In addition to detecting an event, the seismometers can help locate where any debris may have fallen. Tracking debris is important because some space debris can contain toxic materials that can harm the surrounding environment.
The article notes reports of the uncontrolled reentry into Earth's atmosphere of at least 951 objects larger than one square meter from 2010 to 2022.
"On average, objects heavier than 1,000 pounds came down about every 8 days... In fact, the threat of getting hit by uncontrolled orbital reentries has increased by a factor of four from 2010 to 2023, said Luciano Anselmo, who published a study assessing the risk."
Barn door (Score:2)
While helpful to know how often this is happening, it seems like bolting the barn door after the horse has legged it.
The nightmare scenario is that we find some mega constellation has a flaw that is going to result in many of them reaching the surface, or contains something that is causing problems when it burns up during re-entry. Hundreds or even thousands of them, and no easy way to deal with the problem.
NO they can just add data (Score:2)
They're called seismometers but don't that stop the hype. They detect earthquake intensity, not "space junk".
Betteridges law of headlines says no.
Science, realty, and facts say no:
Earthquake sensors are so unreliable to do anything other than detect earthquakes that they won't detect space junk or anything other than what they were deisgned to do.
For one example see https://www.google.com/search?... [google.com]
There are many other areas where seismomometers have been shown to be useless in detecting or pinpointing any
951 objects? (Score:1)
"at least 951 objects larger than one square meter "
Wow, that's a lot of starlink junk falling. On top of it, they are apparently two dimensional, does that make them of infinite density? Are they more dangerous than the 2D nanoparticles in the covid vaccine that slice our blood wessels causing an unseen epidemic of heart attacks?
how can it tell the difference (Score:2)
Re: (Score:2)
Just as I, having seen many a Photoshop in my life, can tell by the pixels, so can they - presumably by the sound pixels.
Re: (Score:3)
They use a network of sensors, and can compute the position of the signal, and they also have the time evolution.
Earthquake are extended in space (along a fault), and time (lasts 30 seconds), the shock waves follow specific patterns, and can be triangulated to inside earth (hypocentre). On the contrary, a meteor (space junk) is a very localized single shock. A quarry explosion could have a similar signature, except it can be triangulated to within a known quarry.
Local events like trucks passing in the campu
Did seismometers detect Tunguska? (Score:3)
I think they existed in 1908
Re:Did seismometers detect Tunguska? (Score:4, Informative)
Yes, they did, as described here:
Source parameters of the siberian explosion of June 30, 1908, from analysis and synthesis of seismic signals at four stations
Old seismograms of the Tungus event of June 30, 1908, are analysed and compared with contemporary records of air explosions from Novaya Zemlya and Lop-Nor.
Observed arrival times and absolute amplitudes of Rayleigh waves, infrasonic-coupled ground-motion and SH crustal shear waves at Jena, Tiflis, Tashkent and Irkutsk, support a source model which consists of a combined action of an atmospheric-explosion equivalent to a vertical point impulse of magnitude 7 1018 dyn sec and a ballistic-wave equivalent to a horizontal point impulse of magnitude 1.4 1018 dyn sec striking S65E toward the northwest.
All the accumulated knowledge in earthquake and explosion seismology since the beginning of the century is harnessed to the effort of interpreting the observed seismograms. The agreement between the observations in the epicentral area and the ensuing signals in the far seismic and acoustic field support the hypothesis that the Siberian UFO explosion had the effects of an Extraterrestrial Nuclear Missile of yield 12.5 ± 2.5 Mt.
https://www.sciencedirect.com/... [sciencedirect.com]
Re: (Score:3)
They did record the event with European seismographs, though they did not record it as precisely as modern instruments would. From the encyclopedia comments, there was quite a lot of "What the hell was *THAT*???" when they realized the range and power of what their instruments measured.
70% WATER !! (Score:2)
If lucky, a sensor net might pickup strikes on soil above decent bedrock. But at least 70% of earth's surface is covered by water with will dissipate much and transmit little to the underlying bedrock. Falls are pseudorandom, perhaps more or less since most of the falling satellites (geosync don't fall) are on polar orbits.
If I were them, I'd be looking for ocean anomalies. Ripples in a pond.
Re: (Score:3)
What? Most falling satellites are coming from LEO, not geo-synchronous orbits. Geo-synchronous orbits are far more expensive to achieve, especially for bulky satellites, and far less likely to have its orbit decay in the time since humanity achieved space flight. Geosynchronous payloads also cost roughly 10 times as much per pound as LEO payloads for delivery to orbit, so they're used quite sparingly and with the lightes tpossible spacecraft.
This is pretty basic rocket science, the sort of thing that Robert
Re: (Score:2)