[Hans] wanted to see the frequency response of a bandpass filter but didn’t have a lot of test equipment. Using an RTL-SDR dongle, some software and a quickly made noise generator, he still managed to get a rough idea of the filter’s characteristics.
How did he do it? He ‘simply’ measured his noise generator frequency characteristics with and without the bandpass filter connected to its output and then subtracted one curve with the other. As you can see in the diagram above, the noise generator is based around a zener diode operating at the reverse breakdown voltage. DC blocking is then done with a simple capacitor.
Given that a standard RTL-SDR dongle can only sample a 2-3MHz wide spectrum gap at a time, [Hans] used rtlsdr-scanner to sweep his region of interest. In his write-up, he also did a great job at describing the limitations of such an approach: for example, the dynamic range of the ADC is only 48dB.
Scientists are always pushing the boundaries in hopes of discovering something truly cutting edge in every sense of the term. Each and every one of these discoveries originated in the mind of someone who perhaps didn’t realize the extent of their abilities. However, one must not discount the power held by those of us ‘amateurs’ who become utterly enthralled in certain subjects ranging from the arts (music, film, photography), to philosophy, all the way to science and astronomy. It’s doubly cool when the arts entwine with science. One great example of that from the science fiction genre is the Star Wars series. The protagonist of the movies hails from a planet in a galaxy, far, far away that circled two suns, named Tatooine. In another classic case of “true life” mimicking the arts, astronomers found a planet circling not two, but four stars. The most amazing aspect of this find? The planet was discovered by two so-called “armchair” astronomers!
HOW THE PLANETS WAS FOUND:
There are many different methods astronomers utilize to to find exoplanets (or extrasolar planets). One such method used by scientists is the transit method. It essentially monitors select stars, in hopes of observing telltale blimps in the luminosity of the star’s light, which is obstructed as a planet transits the face of the star directly in our path of vision. Since observing these so-called blimps of light can be tedious work for astronomers simply based on the large number of stars in the Milky Way alone, the ingenious “Planet Hunters” project was thought up as away to not only discover transiting exoplanets, but as a way to get the public interested in astronomy and other branches of planetary science. Participants can pour through the data collected from 150,000 stars by the Kepler Space telescope (pre-melt down), looking for these blimps of light. This is how this planet was discovered.
Formally dubbed PH1 (“PH” after “Planet Hunters:” the project credited with the discovery) — this undoubtedly bright new world, which lies about 5,000 light-years from Earth, comes in with a radius that exceeds our home world by about 6 times (similarly, it’s about five times more massive). This would essentially make the exoplanet only a small fraction larger than Neptune, the outermost icy giant of our solar system. Yet unlike Neptune, which takes 165 YEARS to make one lap around the sun, PH1 only takes 138 days to complete a single orbit around its two ‘primary’ parent stars (one is about 1.5 times larger than the sun, while the other is about 0.41% more massive). The two stars are in a tight orbit that sees them make one full circle around each other once every 20 days!
Here’s where things get kind of tricky.. The other two stars in the planetary system orbit the primary stars from a distance of about 1,000 AU (1 AU is the distance that separates the Earth and the Sun, which equals out to about 93 million miles [150 million km]). Our solar system is estimated to extend some 160 AUs from the sun, which is the region where the sun’s gravitational influence on solar winds starts to dwindle (we call this the ‘heliosphere.’) Obviously, there is quite a bit of distance between the pair of binary star systems, but that distance is nothing when compared to the distances that typically separate stars and/or planets.
Don’t expect any extra-terrestrial beings to be able to catch a quadruple sunset or sunrise though, this planet is likely composed of gas and is blisteringly hot. The estimates for the temperatures are between 484 degrees Fahrenheit (524 Kelvin, or 251 degrees Celsius) and 644 degrees F (613 Kelvin, or 340 degrees C) — effectively putting the planet outside of the theoretical Goldilocks region of the planetary system (the place where liquid water may exist on the surface without freezing or evaporating. You know, if the planet even had a surface).
ARE THESE PLANETS RARE?
Actually, no. Astronomers have known for a while now that a large portion of the stars in our galaxy belong to multiple star systems. They’ve also found that many binary star systems are locked in tight orbits around other pairs of binary stars. They’ve even found a handful of “Tatooine-like” exoplanets, called circumbinary planets, orbiting a pair of stars. This, however, was the first discovery of its kind. Prior to it, no other exoplanet had ever been discovered orbiting binary stars that, in turn, have stellar companions orbiting them. It’s an interesting find that ultimately challenges our planetary formation theories, which can’t currently explain how a planetesimal could evolve into a fully-fledged planet in such a chaotic environment.
If you’re interested in discovering your own planet — perhaps in hopes of having a planet named after you eventually (hey, we can dream right?) — You can learn more about the Planet Hunters project, which runs solely on volunteers like YOU, here.
[Uli Kilian] — best known for solving 100 Rubik’s cubes during the 2011 London Marathon — got addicted to a free iPad game called Jurassic Park builder. Being the efficient man he is, he soon realized the game could be automated — after all, you just have to tap on dinosaurs every few minutes to earn in-game currency…
He’s using a Lego Technic set with an old iPad, and an Arduino connected to a Windows laptop. Wheels roll the iPad back and forth as the robot plays the game. The “finger” of the robot is wrapped in tin-foil and connected to a ground pin to simulate a human finger for the iPad. The article doesn’t explain how it works, but by looking at the robot it appears to just randomly tap away back and forth across the screen — which we guess works for this game?
He hasn’t played with Lego since he was 8, and only just learned about the Arduino a few weeks prior to building this. As a 3D artist he was intrigued to do something in the real-world — nice!
This is the first image of the Earth captured by the Mars Color Camera (MCC) on board India’s Mars Orbiter Spacecraft. It was taken on 29 November 2013 from an altitude of 67 975 km with a resolution of 3,53 km. Successfully launched into Earth orbit on 5 November 2013, the Mars Orbiter Mission (MOM),...
Today's picture is from around 1920, and it shows some passengers in the observation car of a passenger train. From the looks of it, I would guess you needed some sort of first class ticket to access this car.
Google has been in the crosshairs of the entertainment industries for a while now. These companies believe that Google is not doing enough to prevent pirate sites from showing up in search results.
However, there is another less visible problem that cropped up in recent months. Increasingly, streaming portals with a focus on the latest pirated copies and TV-shows are using Google as a source.
A German anti-piracy outfit has identified more than 18,000 pirated videos that are featured on more than a dozen large sites. All these streaming sites use the same movie sources without charge, and the bandwidth bill goes to Google.
The list of sites includes Movie4k.to, hdmoviezone.net, viooc.co, viooz.be, viooz.cc, vioozmovies.me, watch32.com, putlocker.bz, putocker.to, putlocker.tw, megashare.info, megashare.sh, megashare.ca, afdah.com, yify.tv, watch32.com.
Together these streaming portals are good for several million daily visitors, which means that Google must be seeing a lot of traffic originating from these sites. The screenshot below shows a copy of The Wolf of Wall Street on YIFY.tv, available in several video qualities and with subtitles if needed.
YIFY.tv Using Google
It’s unclear where the videos are hosted, but the URL above shows the googlevideo.com domain. In addition, it includes a “source=picasa” string, suggesting Google’s image hosting service has something to do with it.
While the site owners are benefiting from the free storage, copyright holders are less excited. A German media outfit, which remains unnamed, reportedly sent requests to Google last month hoping to take down the files, but without success.
Since the files remain online, the lawyers of the media company have now applied for an injunction against Google at a local court.
Two weeks ago Warner Bros. also asked Google to remove several of these URLs from its search engine. These requests were denied, most likely because the videos can’t be accessed directly through the link Warner provided.
In a comment to TorrentFreak, Google stresses that users are not permitted to distribute copyrighted content without permission. The company is actively trying to stop these kinds of abuses and also responds swiftly to takedown notices.
“We also respond quickly to disable access to any materials on our platforms identified to us by copyright owners as infringing,” Google adds.
Why the thousands of Google-hosted videos on these streaming portals remain online is unclear. It could be that Google indeed removed the files in question, but that they were re-uploaded. Another possibility is that the copyright holder didn’t correctly identify the source file, as Warner Bros’ takedown notice suggests.
One of the additional problems copyright holders face is that the URLs of the videos are harder to identify. Automated takedown tools can’t easily spot where the files are coming from, which makes it more complicated to send takedown requests.
It will be interesting to see how this issue will be dealt with in the future. It’s clear that neither Google not the copyright holders are happy with the current situation. For now, the only ones benefiting are the streaming portals and their millions of users.
These galaxies, known as NGC 5965 and NGC 5963, are located in the constellation Draco. Even though they appear close in the sky, these galaxies are actually separated by about 110-million light-years.
NGC 5965 is seen nearly edge-on from our vantage point here on Earth. The galaxy itself is about 150-million light-years away and about 200,000 light-years across. Its counterpart, NGC 5963, is much smaller. In stark opposition to NGC 5965, NGC 5963 appears nearly face-on to us. This – along with the fact that NGC 5963 is more faint – can make it a little bit more difficult to gauge how much more distant the other galaxy is from us and the other galaxy (its 40-million light-years away, to be precise).
Furthermore, in this frame, you can also see several other galaxies lurking in the background. Almost all of these large balls of light in the foreground are stars that belong to the Milky Way, which means that they can be no farther than 100,000 light-years away.
Security experts at ESET detected a new variant of iBanking Trojan offered in the underground that exploits Facebook platform as vector of infection.
iBanking is the name of a mobile banking Trojan app distributed through HTML injection attacks on banking sites. iBanking deceives victims impersonating itself as a ‘Security App‘ for Android, we have spoken about it early 2014 when the source code of the mobile malware has been leaked online through an underground forum.
iBanking mobile banking Trojan is available for sale in the underground for $5,000 according the RSA’s FraudAction Group, the malware is used to avoid the security mechanisms implemented by the banking websites, including two-factor authentication.
iBankingcould be commanded via SMS or over HTTP beaconing C&C server every pre-defined interval, then pull and execute the command if one is awaiting it. Thebot implements the following features:
Capture all incoming/outgoing SMS messages
Redirect all incoming voice calls to a different pre-defined number
In/out/missed call-list capturing
Audio capturing via device’s microphone
Phone book capturing
URL status: the mobile device will visit a provided URL, returning its status (possibly for click-fraud schemes.)
Experts at ESET security firm discovered a new variant of iBanking trojan which is exploiting Facebook as vector of infection.
According a report issued by ESET security researchers, the new version of iBanking, aka Android/Spy.Agent.AF, is targeting Facebook users by tricking them to download a malware application.
The above verification page that was designed to request victims, their mobile number in order to verify the Facebook account authenticity. In case the SMS fails to reach the user’s mobile, one of the successive pages was designed to requestvictim to download an Android app from an URL displayed or reading a QR code proposed on the screen,.
Once downloaded iBanking, the bot start its activities, it connects to the C&C server to receive commands.
iBanking, or any other similar malware, represents a privileged choice for cyber criminals due its ability to bypass two-factor authentication, criminal underground is increasing its offer especially oriented to mobile solutions. iBanking is considered a sophisticated solution according experts at ESET which compared it to other banking trojan like Perkele
“iBanking, detected by ESET as Android/Spy.Agent.AF, is an application that showcases complex features when compared with other earlier mobile banking malware, such as Perkele. It can be used in conjunction with any malware able to inject code into a webpage and is generally used to redirect incoming SMS messages to bypass two-factor authentication.” reported ESET.
Another alarming hypothesis is this Facebook iBanking app might be distributed by other banking malware in the next months, cybercriminals could start to adopt mobile components to attack other popular web services that enforce strong authentication.
The “commoditization” of malicious code and the code source leaks will sustain an offer that will increase in complexity and efficiency.
Spatial Data Structures Prompt Award
Hanan Samet, a Distinguished University Professor of Computer Science at the University of Maryland, has been named the 2014 recipient of the IEEE Computer Society's prestigious W. Wallace McDowell Award for his contributions to spatial... Continue reading
The great thing about standards is that there are so many to choose from. Filament spools certainly do not deviate far from this sarcastic saying. So what are we 3D Printer folks to do? Here are a couple completely different DIY options:
[Mark] made a spool holder that can accept 2 different width spools. This design uses skate bearings to support the spool on two points at each end. There are 3 sets of bearing blocks to accommodate the 2 different width spools. When either size spool is installed, one of the bearing block sets goes unused.
[Ben] took a different approach to the same problem. His design holds the spool on its side making the spool width have no affect on the holders’ functionality. The parts for this spool holder are recycled from an old computer CD drive. If we’d have to suggest anything, it would be to add a little resistance to the spinning turntable to prevent uncontrolled filament unraveling (we’ve all been there).
A Batch Picture Resizer is software that anyone who works with digital photos will find extremely useful. With this simple and cheap program, you can resize any amount of images quickly. The picture resizer can be used to reduce the size of your photos so that they are more appropriate for publishing on the Internet, emailing to family and friends or simply to save space on your hard drive.
The highest quality possible is also preserved in the files. Batch Picture Resizer also provides the possibility to change the color levels of your pictures or add text and watermarks to group of photos quickly.
It’s time once again for a roundup of ancient hardware that has successfully loaded our retro edition. Up this time is a completely random and totally not planned roundup of parallel port to Ethernet adapters.
First up is [Tom Moss] with his IBM 5150 – the first ‘IBM Compatible’ home computer, progenitor of the i7 boxxen warming your ankles as you read this. This machine comes standard with a 4.77 MHz 8088 CPU, 8087 FPU, 512k RAM, two 360k 5.25″ floppy drives, and a few very cool additions: an ISA to CompactFlash card adapter, giving [Tom]‘s box 4GB of storage.
How is [Tom] connecting to the Internet? A Xircom PE3-10BT Network Adapter. This neat device turns any parallel port into an Ethernet. With a Telnet program, [Tom] was able to connect to a Unix system and use Lynx to browse over to the retro site. He’s yet to get a DOS browser working, but FTP is go, allowing him to download ancient software directly onto his huge CF card.
The next one isn’t exactly vintage, but it does carry the spirit of antiquated hardware onto the web. [Valentin] is using a FleaFPGA and a 186 over at OpenCores. The FPGA board gives him VGA output, an SD card, A PS/2 keyboard, but no options for networking. That’s no problem for [Valentin], as he wired up a Xircom PE3 parallel port to Ethernet adapter. Yes, the same adapter as the 5150 above. [Valentin] says his parallel port hack is a bit of a mess with non-bidirectional and no dedicated IRQ hardware support. It works, though, so we can’t fault him for that.
We’re always looking for people who have loaded our retro edition on old hardware. If you have some outdated hardware sitting in the attic, get it out, load up Hackaday Retro, and send it in.
In her keynote address at the GEOINT Symposium, National Geospatial-Intelligence Agency (NGA) Director Letitia Long continued to refine and define her vision for the preeminent government geospatial technology agency. It's a vision that began in 2010 with identifying the needs of the... Continue reading
[Keith] wanted to make a completely open source instrument that’s elegant, useful, and a bit more accessible than the servoelectric guitar, so he teamed up with a hacker/electronic music expert and an industrial designer. He built the early prototypes around an Arduino Uno. The current iteration uses a Teensy 2.0 and is available in various forms through Kickstarter. [Keith] opened the Kyub up to crowd funding in an effort to obtain volume pricing on some of the parts as well as an Eagle license to make the PCB files available commercially.
The Kyub has eleven pressure-sensitive capacitive keypads on five sides of the cube. The accelerometer can be used to vary note volume, bend the pitch, or whatever else you program it to do. Of course, you’ll need a computer with a synthesizer program, but [Keith] says it is compatible with most software synth programs, some of which are free.
There’s a demo video of an early prototype after the break. Videos of the Kyub in its current form are available on the Kickstarter page.
If you’re like me, you have been on more than one road trip where you forgot to carry along your car charger. Then, once you get to your destination, you have to wait around forever before you can hit the road again, as your phone takes ages and ages to charge. Okay, perhaps that’s a bit dramatic, but in this fast-paced world, people appreciate any technology that allows them to do things faster and more efficiently. And this latest bit of technology is definitely faster. Recently a startup company, StoreDot, announced that they have created a battery pack that can fully charge your phone in a mere 30 seconds.
This device is able to function so efficiently thanks to microscopic magnets that are called “nano dots.” Nano dots are bio-organic nano crystals that are only 2 nanometers in size. StoreDot explains their research by stating that they have been developing biological semiconductors that are made from naturally occurring organic compounds called peptides, short chains of amino acids, the building blocks of proteins. Ultimately, this allows the company to greatly decrease the charging time on batteries. The company adds, “When applying nanodots in flash memory storage data is written 3 times faster than the traditional floating gate technology. Image sensors utilizing this technology are 5 times more sensitive than existing sensors.”
It may seem like this device would cost an arm and an leg, but it is actually shockingly inexpensive. The company estimates that it would cost about twice as much as a normal charger, so perhaps 60$ max. Commercial production of this device is set to start in 2016, which may be a ways away, but at least you will be able to get a head start on your Kwanzaa/Christmas/Hanukkah list.