It may be midwinter in Perth, but people still go to the beach there, which led to the surprising discovery earlier this week of what appears to be a large hunk of space debris. Local authorities quickly responded to reports of a barnacle-encrusted 2.5-m by 3-m tank-like object on the beach. The object, which has clearly seen better days, was described as being made of metal and a “wood-like material,” which on casual inspection is clearly a composite material like Kevlar fibers in some sort of resin. Local fire officials teamed up with forensic chemists to analyze the object for contamination; finding none, West Australia police cordoned off the device to keep the curious at bay. In an apparently acute case of not knowing how the Internet works, they also “urge[d] everyone to refrain from drawing conclusions” online, which of course sent the virtual sleuths into overdrive. An r/whatisthisthing thread makes a good case for it being part of the remains of the third stage of an Indian Polar Satellite Launch Vehicle (PSLV); reentry of these boosters is generally targeted at the East Indian Ocean for safe disposal, but wind and weather seem to have brought this artifact back from the depths.
The simplest way to look for meteors is to go outside at night and look up — but it’s not terribly effective. Fortunately, there’s a better way: radio. With a software-defined radio and a little know-how from [Tech Minds], you can easily find them, as you can see in the video below.
This uses the UK meteor beacon we’ve looked at before. The beacon pushes an RF signal out so you can read the reflections from meteors. If you are too far from the beacon, you may need a special antenna or you might have to find another beacon altogether. We know of the Graves radar in France and we have to wonder if you couldn’t use some commercial transmitter with a little experimentation.
[Tech Minds] has some practical tips to share if you want to try doing it yourself. If you want to see what a detected meteor looks like, you can visit the UK beacon’s gallery page.
After passing an exam and obtaining a license, an amateur radio operator will typically pick up a VHF ratio and start talking to other hams in their local community. From there a whole array of paths open up, and some will focus on interesting ways of bouncing signals around the atmosphere. There are all kinds of ways of propagating radio waves and bouncing them off of various reflective objects, such as the Moon, various layers of the ionosphere, or even the auroras, but none are quite as fleeting as bouncing a signal off of a meteor that’s just burned up in the atmosphere.
While they aren’t specifically focused on communicating via meteor bounce, The UK Meteor Beacon Project hopes to leverage amateur radio operators and amateur radio astronomers to research more about meteors as they interact with the atmosphere. A large radio beacon, which has already been placed into service, broadcasts a circularly-polarized signal in the six-meter band which is easily reflected back to Earth off of meteors. Specialized receivers can pick up these signals, and are coordinated among a network of other receivers which stream the data they recover over the internet back to a central server.
With this information, the project can determine where the meteor came from, some of the properties of the meteors, and compute their trajectories by listening for the radio echoes the meteors produce. While this is still in the beginning phases and information is relatively scarce, the receivers seem to be able to be built around RTL-SDR modules that we have seen be useful across a wide variety of radio projects for an absolute minimum of cost.
Space is very much the final frontier for humanity, at least as far as our current understanding of the universe takes us. Only a handful of countries and corporations on Earth have the hardware to readily get there, and even fewer are capable of reaching orbit. For these reasons, working in this field can seem out of reach for many. Nevertheless, there’s plenty about the great expanse beyond our atmosphere that can be studied by the dedicated citizen scientist. With the right equipment and know-how, it’s even possible to capture and study micrometeorites yourself!
For those new to the field, the terms used can be confusing. Meteoroids are small metallic or rocky objects found in outer space, up to around 1 meter in size. When these burn up upon entering the atmosphere, they are referred to as a meteor, or colloquially known as a shooting star. If part of the object survives long enough to hit the ground, this is referred to as a meteorite, and as you’d expect the smaller ones are called micrometeorites, being on the scale of 2mm or less.
Stardust Proves Hard To Find
Being tiny and having fallen from space, micrometeorites present certain challenges to those who wish to find and identify them. In spite of this, they can be found by using the right techniques and a heck of a lot of hard work.
According to ancient astronaut theorists, the lunar eclipse this weekend had an unexpected visitor. Right around the time of totality, a meteoroid crashed into the moon, and it was visible from Earth.
Meteoroids crash into the Earth and Moon all the time, although this usually happens either over the ocean (70% of the Earth) where we can’t see it, on the far side of the moon (~50% of the Moon) where we can’t see it, or on the sunlit side of the Moon (another, different 50%), where we can’t see it. These meteoroids range from the size of a grain of sand to several meters across, but only the largest could ever be seen by the human eye. This weekend’s lunar eclipse, the Super Blood Wolf Moon was visible to a large portion of the population, and many, many cameras were trained on the Moon. Several telescopes livestreamed the entire eclipse, and multiple people caught a glimpse of a small flash of light, seeming to come from around Lagrange crater. Because this event was seen by multiple observers separated by thousands of miles, the only conclusion is that something hit the moon, and its impact event was recorded on video.
This is not the first time an impact event has been recorded on the moon. The Moon Impacts Detection and Analysis System (MIDAS) running out of La Hita Observatory has regularly recorded impact events, including one that was comparable to an an explosion of 15 tons of TNT. These automated observatories aren’t running during a full moon, like during a lunar eclipse, because no camera would be able to pick up the flash of light. We were somewhat lucky last weekend’s impact happened during totality, and with dozens of cameras trained on the Moon.
Further investigation will be necessary to determine the size of the meteoroid and obtain pictures of its impact crater, but for a basis of comparison, the LCROSS mission plowed a Centaur upper stage (2.2 tons) into the lunar surface at 2.5 km/s. This should have resulted in a flash visible through binoculars, but it didn’t. The meteoroid that struck the moon last weekend would have been traveling faster (a minimum of about 12 km/s), but the best guess is that this rock might have been of suitable size to have fit in the back of a pickup truck, or thereabouts.
It’s not hard to detect meteors: go outside on a clear night in a dark place and you’re bound to see one eventually. But visible light detection is limiting, and knowing that meteors leave a trail of ions means radio detection is possible. That’s what’s behind this attempt to map meteor trails using broadcast signals, which so far hasn’t yielded great results.
The fact that meteor trails reflect radio signals is well-known; hams use “meteor bounce” to make long-distance contacts all the time. And using commercial FM broadcast signals to map meteor activity isn’t new, either — we’ve covered the “forward scattering” technique before. The technique requires tuning into a frequency used by a distant station but not a local one and waiting for a passing meteor to bounce the distant signal back to your SDR dongle. Capturing the waterfall display for later analysis should show characteristic patterns and give you an idea of where and when the meteor passed.
[Dave Venne] is an amateur astronomer who turns his eyes and ears to the heavens just to see what he can find. [Dave]’s problem is that the commercial FM band in the Minneapolis area that he calls home is crowded, to say the least. He hit upon the idea of using the National Weather Service weather radio broadcasts at around 160 MHz as a substitute. Sadly, all he managed to capture were passing airplanes with their characteristic Doppler shift; pretty cool in its own right, but not the desired result.
The comments in the RTL-SDR.com post on [Dave]’s attempt had a few ideas on where this went wrong and how to improve it, including the intriguing idea of using 60-meter ham band propagation beacons. Now it’s Hackaday’s turn: any ideas on how to fix [Dave]’s problem? Sound off in the comments below.
NASA has been tracking bright meteoroids (“fireballs”) using a distributed network of video cameras pointed upwards. And while we usually think of NASA in the context of multi-bazillion dollar rocket ships, but this operation is clearly shoe-string. This is a hack worthy of Hackaday.
The basic idea is that with many wide-angle video cameras capturing the night sky, and a little bit of image processing, identifying meteoroids in the night sky should be fairly easy. When enough cameras capture the same meteoroid, one can use triangulation to back out the path of the meteoroid in 3D, estimate its mass, and more. It’s surprising how many there are to see on any given night.
You can watch the videos of a meteoroid event from any camera, watch the cameras live, and even download the meteoroid’s orbital parameters. We’re bookmarking this website for the next big meteor shower.
The work is apparently based on [Rob Weryk]’s ASGARD system, for which the code is unfortunately unavailable. But it shouldn’t be all that hard to hack something together with a single-board computer, camera, and OpenCV. NASA’s project is limited to the US so far, but we wonder how much more data could be collected with a network of cameras all over the globe. So which ones of you are going to take up our challenge? Build your own version and let us know about it!
Between this project and the Radio Meteor Zoo, we’re surprised at how much public information there is out there about the rocky balls of fire that rain down on us every night, and will eventually be responsible for our extinction. At least we can be sure we’ll get it on film.