Before Sending A Probe To The Sun, Make Sure It Can Take The Heat

August 15, 2018 by Roger Cheng 61 Comments

This past weekend, NASA’s Parker Solar Probe took off for a journey to study our local star. While its mission is well covered by science literate media sources, the equally interesting behind-the-scenes information is a little harder to come by. For that, we have Science News who gave us a look at some of the work that went into testing the probe.

NASA has built and tested space probes before, but none of them were destined to get as close to the sun as Parker will, creating new challenges for testing the probe. The lead engineer for the heat shield, Elizabeth Congdon, was quoted in the article: “Getting things hot on Earth is easier than you would think it is, getting things hot on Earth in vacuum is difficult.” The team used everything from a concentrated solar facility to hacking IMAX movie projector lenses.

The extreme heat also posed indirect problems elsewhere on the probe. A rocket launch is not a gentle affair, any cargo has to tolerate a great deal of shock and vibration. A typical solution for keeping fasteners in place is to glue them down with an epoxy, but they’d melt where Parker is going so something else had to be done. It’s not all high technology and exotic materials, though, as when the goal was to verify that the heat shield was strong enough to withstand up to 20G of acceleration expected during launch, the test team simulated extra weight by stacking paper on top of it.

All that testing should ensure Parker can perform its mission and tell us a lot of interesting things about our sun. And if you got in on the publicity campaign earlier this year, your name is along for the ride.

Not enough space probe action for the day? We’ve also recently featured how creative hacking gave the exoplanet hunter Kepler a second lease on life.

The Photo Lab That Flew To The Moon

August 2, 2018 by Dan Maloney 12 Comments

When planning a trip by car these days, it’s pretty much standard practice to spin up an image of your destination in Google Maps and get an idea of what you’re in for when you get there. What kind of parking do they have? Are the streets narrow or twisty? Will I be able to drive right up, or will I be walking a bit when I get there? It’s good to know what’s waiting for you, especially if you’re headed someplace you’ve never been before.

NASA was very much of this mind in the 1960s, except the trip they were planning for was 238,000 miles each way and would involve parking two humans on the surface of another world that we had only seen through telescopes. As good as Earth-based astronomy may be, nothing beats an up close and personal look, and so NASA decided to send a series of satellites to our nearest neighbor to look for the best places to land the Apollo missions. And while most of the feats NASA pulled off in the heyday of the Space Race were surprising, the Lunar Orbiter missions were especially so because of how they chose to acquire the images: using a film camera and a flying photo lab.

Continue reading “The Photo Lab That Flew To The Moon” →

Conquering The Earth With Cron

June 25, 2018 by Tom Nardi 15 Comments

The GOES-R series of Earth observation satellites are the latest and greatest NASA has to offer. As you might expect, part of the GOES-R job description is imaging Earth at high-resolution, but they also feature real-time lighting monitoring as well as enhanced solar flare and space weather capabilities. Four of these brand new birds will be helping us keep an eye on our planet’s condition into the 2030s. Not a bad way to spend around 11 billion bucks.

To encourage innovation, NASA is making the images collected by the GOES-R satellites available to the public through a collaboration with Google Cloud Platform. [Ben Nitkin] decided to play around with this data, and came up with an interactive website that let’s you visualize the Earth from the perspective of GOES-R. But don’t let those slick visuals fool you, the site is powered by a couple cron jobs and some static HTML. Just as Sir Tim Berners-Lee intended it.

But it’s not quite as easy as scheduling a wget command; the images GOES-R collects are separated into different wavelengths and need to be combined to create a false-color image. A cron job fires off every five minutes which downloads and merges the raw GOES-R images, and then another cron job starts a Python script that creates WebM time-lapse videos out of the images using ffmpeg. All of the Python scripts and the crontab file are available on GitHub.

Finally, with the images merged and the videos created, the static HTML website is served out to the world courtesy of a quick and dirty Python web server. The site could be served via something more conventional, but [Ben] likes to keep overhead as low as possible.

If you want to take the more direct route, we’ve covered plenty of projects focused on pulling down images from weather satellites; from using old-school “rabbit ears” to decoding the latest Russian Meteor-M N2 downlink.

Continue reading “Conquering The Earth With Cron” →

Get Your Name On The Hottest List In The Solar System

April 12, 2018 by Brian McEvoy 29 Comments

How often does NASA name a spacecraft after a living person? How often do you get to launch your name into a star? How often does NASA send probes to explore the sun? If your answer to all these questions is NEVER, then you win the honor of adding your name to an SD card bound for the center of our solar system. We’re already on the list with [William Shatner] so we’ll see you there. Submissions for the hot list aboard the Parker Solar Probe close on April 27th, 2018 and it launches in May.

The Parker Solar probe honors living astrophysicist [Eugene Parker] who theorized a great deal about how the sun, and other stars, emit energy. His work has rightly earned him the honor of seeing his name on a sun-bound probe. We even owe the term, “solar wind” to [Parker].

To draw more attention, you can have a few bits aboard this probe dedicated to you or someone you care about by adding your name to their list. Or you can send the name of your greatest enemy into the hottest furnace for millions of miles. Your call.

Even though our sun is the most prominent heavenly body, NASA hasn’t sent a probe to explore it before. They are good about sharing their models and they really know how to write standards for workmanship.

Continue reading “Get Your Name On The Hottest List In The Solar System” →

Lockheed Shares Satellite Connectivity Options

March 17, 2018 by Kerry Scharfglass 12 Comments

In an unusual turn of events, Lockheed Martin has released technical “payload accommodation information” for three of their satellite busses. In layperson’s terms, if you wanted to build a satellite and weren’t sure what guidelines to follow these documents may help you learn if Lockheed Martin has a platform to help you build it.

An opportunity to check out once-confidential information about satellites sounds like a perfect excuse to dig through some juicy documentation, though unfortunately this may not be the bonanza of technical tidbits the Hackaday reader is looking for. Past the slick diagrams of typical satellites in rocket fairings, the three documents in question primarily provide broad guidance. There are notes about maximum power ratings, mass and volume guidelines, available orbits, and the like. Communication bus options are varied; there aren’t 1000BASE-T Ethernet drops but multiply redundant MIL-STD-1553B might come standard, plus telemetry options for analog, serial, and other data sources up to 100 Mbps. Somewhat more usual (compared to your average PIC32 datasheet) are specifications for radiation shielding and it’s effectiveness.

In the press release EVP [Rick Ambrose] says “we’re sharing details about the kinds of payloads we can fly…” and that’s exactly what these documents give us. Physical ballpark and general guidelines about what general types of thing Lockheed has capability to build launch. Hopefully the spirit of openness will lead to the hoped-for increase in space utilization.

If you take Lockheed up on their offer of satellite development, don’t forget to drop us a tip!

[Via the Washington Post]

At 71,572 KM, You Won’t Beat This LoRa Record

February 22, 2018 by Jenny List 29 Comments

A distance record for LoRa transmission has been set that you probably won’t be able to beat. Pack up your gear and go home, nothing more to achieve here. At a superficial reading having a figure of 71,572 km (44,473 miles) seems an impossible figure for one of the little LoRa radio modules many of us have hooked up to our microcontrollers, but the story isn’t quite what you’d expect and contains within it some extremely interesting use of technology.

So the folks at Outernet have sent data over LoRa for that incredible distance, but they did so not through the little ISM band modules we’re used to but over a suitably powerful Ku-band uplink to a geostationary satellite. They are also not using the LoRaWAN protocols of the earthbound systems, but simply the LoRa modulation scheme. So it’s not directly comparable to terrestrial records such as the 702 km we reported on last year, and they are the first to admit that.

Where their achievement becomes especially interesting though is in their choice of receiver. We are all used to Ku-band receivers, you may even have one on your house somewhere for satellite TV. It will probably involve a parabolic dish with a narrow beam width and an LNB whose horn antenna is placed at its focus. It would have required some skill and effort to set up, because it has to be pointed very carefully at the satellite’s position in the sky. Outernet’s mission of delivering an information service with the lowest possible barrier to entry precludes the extra expense of shipping a dish and providing trained staff to align it, so they take a very different approach. Their receiver uses either an LNB horn or a small patch antenna pointing at the satellite, with none of the dishes or phased arrays you might be used to in a Ku-band installation.

You might wonder how such a receiver could possibly work with such a meagre antenna, but the secret lies in LoRa’s relatively tiny bandwidth as well as the resistance to co-channel interference that is a built-in feature of the LoRa modulation scheme. Even though the receiver will be illuminated by multiple satellites at once it is able to retrieve the signal and achieve a 30 kb/s data rate that they hope with technical refinements to increase to 100 kb/s. This rate will be enough over which to push an SD video stream to name just one of the several examples of the type of content they hope to deliver.

It’s likely that the average Hackaday reader will not be hiring satellite uplink time upon which to place their LoRa traffic. But this story does provide a demonstration of LoRa’s impressive capabilities, and will make us look upon our humble LNBs with new eyes.

Via ABOpen.

Returning A Lost Sheep To The NASA Fold

February 13, 2018 by Jenny List 48 Comments

About three weeks ago, we reported that a satellite enthusiast in Canada found an unexpected signal among his listening data. It was a satellite, and upon investigation it turned out to be NASA’s IMAGE satellite, presumed dead since a power failure in 2005 interrupted its mission to survey the Earth’s magnetosphere.

This story is old news then, they’ve found IMAGE, now move on. And indeed the initial excitement is past, and you might expect that to be it from the news cycle perspective. But this isn’t the Daily Mail, it’s Hackaday. And because we are interested in the details of stories like these it’s a fascinating read to take a look at NASA’s detailed timeline of the satellite’s discovery and subsequent recovery.

In it we read about the detective work that went into not simply identifying the probable source of the signals, but verifying that it was indeed IMAGE. Then we follow the various NASA personnel as they track the craft and receive telemetry from it. It seems they have a fully functional spacecraft with a fully charged battery reporting for duty, the lost sheep has well and truly returned to the fold!

At the time of writing they are preparing to issue commands to the craft, so with luck by the time you read this they will have resumed full control of it and there will be fresh exciting installments of the saga. Meanwhile you can read our report of the discovery here, and read about a previous satellite brought back from the dead.

Picture of IMAGE satellite: NASA public domain.