A schematic representation of the different ionospheric sub-layers and how they evolve daily from day to night periods. (Credit: Carlos Molina)

Will Large Satellite Constellations Affect Earth’s Magnetic Field?

February 7, 2024 by Maya Posch 48 Comments

Imagine taking a significant amount of metals and other materials out of the Earth’s crust and scattering it into the atmosphere from space. This is effectively what we have been doing ever since the beginning of the Space Age, with an increasing number of rocket stages, satellites and related objects ending their existence as they burn up in the Earth’s atmosphere. Yet rather than vanish into nothing, the debris of this destruction remains partially in the atmosphere, where it forms pockets of material. As this material is often conductive, it will likely affect the Earth’s magnetic field, as argued by [Sierra Solter-Hunt] in a pre-publication article.

A summary by [Dr. Tony Phillips] references a 2023 NASA research article by [Daniel M. Murphy] et al. which describes the discovery that about 10% of the aerosol particles in the stratosphere are aluminium and other metals whose origin can be traced back to the ‘burn-up’ of the aforementioned space objects. This is a factor which can increase the Debye length of the ionosphere. What the exact effects of this may be is still largely unknown, but fact remains that we are launching massively more objects into space than even a decade ago, with the number of LEO objects consequently increasing.

Although the speculation by [Sierra] can be called ‘alarmist’, the research question of what’ll happen if over the coming years we’ll have daily Starlink and other satellites disintegrating in the atmosphere is a valid one. As this looks like it will coat the stratosphere and ionosphere in particular with metal aerosols at levels never seen before, it might be worth it to do the research up-front, rather than wait until we see something odd happening.

Balloon To Fly During Solar Eclipse

November 14, 2023 by Bryan Cockfield 9 Comments

The Great American Eclipse was a solar eclipse that passed nearly the entire continental United States back in 2017. While it might sound like a once-in-a-lifetime event to experience a total solar eclipse, the stars have aligned to bring another total solar eclipse to North America although with a slightly different path stretching from the west coast of Mexico and ending off the cost of Newfoundland in Canada. Plenty of people near the path of totality have already made plans to view the event, but [Stephen] and a team of volunteers have done a little bit of extra preparation and plan to launch a high-altitude balloon during the event.

The unmanned balloon will primarily be carrying a solar telescope with the required systems onboard to stream its images live during its flight. The balloon will make its way to the stratosphere, hopefully above any clouds that are common in New Brunswick during the early spring, flying up to 30,000 meters before returning its payload safely to Earth. The telescope will return magnified images of the solar eclipse live to viewers on the ground and has been in development for over two years at this point. The team believes it to be the first time a non-governmental organization has imaged an eclipse by balloon.

For those who have never experienced a total solar eclipse before, it’s definitely something worth traveling for if you’re not already in its path. For this one, Canadians will need to find themselves in the Maritimes or Newfoundland or head south to the eastern half of the United States with the Americans, while anyone in Mexico needs to be in the central part of the mainland. Eclipses happen in places other than North America too, and are generally rare enough that you’ll hear about a total eclipse well in advance. There’s more to eclipses than watching the moon’s shadow pass by, though. NASA expects changes in the ionosphere and is asking ham radio operators for help for the 2024 eclipse.

Hackaday Links: October 22, 2023

October 22, 2023 by Dan Maloney 9 Comments

The second of three major solar eclipses in a mere six-year period swept across the United States last week. We managed to catch the first one back in 2017, and still have plans for the next one in April of 2024. But we gave this one a miss, mainly because it was “just” an annular eclipse, promising a less spectacular presentation than a total eclipse.

Looks like we were wrong about that, at least judging by photographs of last week’s “Ring of Fire” eclipse. NASA managed to catch a shot of the Moon’s shadow over the middle of the US from the Deep Space Climate Observer at Lagrange Point 1. The image, which shows both the compact central umbra of the shadow and the much larger penumbra, which covers almost the entire continent, is equal parts fascinating and terrifying. Ground-based photographers were very much in the action too, turning in some lovely shots of the eclipse. We particularly like this “one-in-a-million” shot of a jet airliner photobombing the developing eclipse. Shots like these make us feel like it was a mistake to skip the 10-hour drive to the path of annularity.

Continue reading “Hackaday Links: October 22, 2023” →

Hackaday Links: May 21, 2023

May 21, 2023 by Dan Maloney 14 Comments

The reports of the death of automotive AM radio may have been greatly exaggerated. Regular readers will recall us harping on the issue of automakers planning to exclude AM from the infotainment systems in their latest offerings, which doesn’t seem to make a lot of sense given the reach of AM radio and its importance in public emergencies. US lawmakers apparently agree with that position, having now introduced a bipartisan bill to require AM radios in cars. The “AM for Every Vehicle Act” will direct the National Highway Transportation Safety Administration to draw up regulations requiring every vehicle operating on US highways to be able to receive AM broadcasts without additional fees or subscriptions. That last bit is clever, since it prevents automakers from charging monthly fees as they do for heated seats and other niceties. It’s just a bill now, of course, and stands about as much chance of becoming law as anything else that makes sense does, so we’re not holding our breath on this one. But at least someone recognizes that AM radio still has a valid use case.

Continue reading “Hackaday Links: May 21, 2023” →

Launching Paper Planes From Way, Waaaaaay Up

May 7, 2023 by Donald Papp 12 Comments

Every now and again we stumble across something a bit unexpected, and today that’s the fact that there have been quite a few efforts at launching paper planes from as close to space as possible. The current record for the highest paper plane launch is a whopping altitude of 35,043 meters.

That altitude is considerably short of what would be called “space”, but it’s still an awfully long way up and the air there is very thin compared to on the surface. Space is generally (but not universally) considered to be beyond 100 km above sea level, a human-chosen boundary known as the Kármán line. 35 km is a long ways into the stratosphere, but still within Earth’s atmosphere.

Even so, that doesn’t mean there haven’t been efforts to go considerably higher. There was a Japanese proposal to drop airplanes made from special heat-resistant paper from the International Space Station, roughly 400 km above Earth. Success would show that low-speed, low-friction atmospheric reentry is feasible — for pieces of paper, anyway. But one of the challenges is the fact that there is no practical way to track such objects on their way down, and therefore no way to determine where or when they would eventually land.

There have been many other high-altitude paper plane launches, but the current record of 35,043 meters was accomplished by David Green in the United Kingdom as part of a school project. Such altitudes are in the realm of things like weather balloons, and therefore certainly within the reach of hobbyists.

As for the airplanes themselves, the basic design pictured here probably won’t cut it, so why not brush up on designs with the Paper Airplane Design Database? Even if you don’t send them into the stratosphere (or higher), you might find something worth putting through a DIY wind tunnel to see how they perform.

Project Loon Will Float LTE To Puerto Rico

October 9, 2017 by Kristina Panos 18 Comments

Some of the biggest names in technology have offered their help in rebuilding Puerto Rico’s infrastructure. The newest name on the list? The X division of Alphabet, who want to help fill the huge communications gap using Project Loon, their high-altitude balloon network. It looks like X is going to get their wish, as they have just been granted license from the FCC to deploy LTE cell coverage to both Puerto Rico and the US Virgin Islands.

The plan is to launch 30 balloons that will act as a network of floating cell towers to radiate an LTE signal originating from the ground. This coverage would be a great boon to a devastated communications infrastructure, but it won’t be a cakewalk to implement. Some handsets of both major persuasions will require a temporary over-the-air update before they can use Project Loon’s network. For phones that can’t operate on Band 8, it won’t work at all. Even so, it’s a great start.

Now you would think that an emergency communications restoration plan like this would be met by all parties with open arms and a circle of pats on the back, but this solution requires a lot of cooperation. One of the major hurdles was to secure spectrum rights from some if not all of the incumbent wireless carriers. Miraculously, eight of them have agreed to hand over their bandwidth. Another issue is that the FCC license is only good for six months, although they would probably entertain an extension given the circumstances. Finally, the dual ownership of the Virgin Islands makes the situation even more complicated, as X must agree not to infringe upon the wireless coverage footprint of the British Virgin Islands.

Via r/Futurology

Deep Sweep: A Home Made SigInt Platform

September 25, 2015 by Richard Baguley 56 Comments

Signals Intelligence (SigInt) isn’t something that you normally associate with home hackers, but the Deep Sweep project is looking to change that: it is a balloon platform that captures radio signals in the stratosphere, particularly conversations between drones and satellites. Created by three students at the Frank Ratchye Studio for Creative Inquiry at Carnegie-Mellon, Deep Sweep is a platform that is attached to a balloon and which captures signals over a wide range of frequencies, logging them for later analysis. The current version captures data on three frequency bands: LF/HF (10KHz-30KHz), UHF (650 – 1650MHz) and SHF (10-20GHz). The latter are often the bands used for satellite links between drones and satellites. They are difficult to intercept from the ground, as the signals are directed upwards towards the satellite. By creating a platform that can fly several kilometers above the earth, they are hoping to be able to capture some of this elusive traffic.

So far, the team has made two flights in Europe, both of which encountered technical issues. The first had a battery fault and only captured 10 minutes of data, and the second flew further than expected and ended up in Belarus, a country that isn’t likely to welcome this kind of thing. Fortunately, they were able to recover the balloon and are working on future launches in Europe and the USA. It will be interesting to see how the Department of Homeland Security feels about this.