• Category Archives Space
  • Gridcoin GPU mining (5): Looking at the Sky

    Besides searching for gravitational waves, Einstein@home is also analyzing data from Arecibo Observatory, Parkes Observatory and Fermi Gamma-ray Space Telescope, searching for pulsars in the electromagnetic spectrum.

    Parkes radio-telescope observatory in Australia

    Compared to the quest for gravitational waves, this is certainly a more conventional search, but nevertheless an enormous computational challenge. So far, 31 new binary radio-pulsars have been discovered in Arecibo data, 24 binary radio-pulsars in Parkes data and 18 new gamma-ray pulsars have been discovered in Fermi Space Telescope data, greatly advancing the overall understanding of these stellar objects. Additionally, such pulsars are a continuous source of gravitational waves (especially binary systems) and are potential candidates for future targeted gravitational wave searches (like S6CasA which ran in 2014. and targeted supernova remnants in the constellation Cassiopeia).

    Einstein@home is looking for pulsars in binary systems (two pulsars orbiting one another, as depicted in this GIF animation, or pulsar plus an ordinary companion star). Since we see most of such binary systems from the side or inclined, their signal is usually ‘smeared’ and harder to distinguish from the background noise. Einstein@home and distributed computing arrive to the rescue, analyzing huge amount of data from various radio-observatories across the world, scanning the electromagnetic spectrum for such hard to detect, smeared signals. Two such massive celestial bodies rotating around each other at a relatively close distance are also a likely source of continuous gravitational waves.

    PSR J1913+1102

    Just recently, in December 2016, two lucky Einstein@home volunteers (Uwe Tittmar from Germany and Gerald Schrader from the US) discovered one such binary system named PSR J1913+1102 – two massive neutron stars orbiting one another in less than five hours (that’s considered a very tight orbit), almost 25 000 light years away from Earth. Such double neutron star systems are very rare, and unique for fundamental physics, enabling measurements that would be impossible to obtain otherwise – literally a ‘golden mine’ for physicists.

    As mentioned before, Einstein@home has discovered a total of 55 different radio pulsars, but PSR J1913+1102 is considered to be its most significant detection so far. You can read more about it here: Home computers discover a record-breaking pulsar-neutron star system. 

    Deciphering the name: PSR=Pulsar, J=so called Julian epoch, 1913=Right Ascension, 1102=Declination. Long story short, these numbers tell us where is this particular celestial object located on our sky. Through this interactive map, you can find out that this pulsar is roughly located in the Aquila constellation:

    The Aquila constellation, best seen in the northern summer sky. It is located along the Milky Way and because of this location (along the line of our Galaxy), many clusters, pulsars, nebulae and other interesting celestial objects are found within its borders – not surprisingly, because the stellar density is much higher there.

    The discovery

    So, what actually happens when you compute for Einstein@home and happen to discover one such pulsar? Well, after the workunit containing such an important signal is crunched through BOINC on your machine, the results are uploaded to Einstein@home servers where they are double-checked and analyzed even further. If such an analysis indeed confirms that your device found the signal with highest statistical significance, you will receive an e-mail from Prof. Bruce Allen, Director of Einstein@home (on e-mail address with which you registered on BOINC in the first place).

    The hardware

    So, you are asking yourself now, what hardware is needed to make all these nice discoveries? Well, almost any CPU or GPU will do. Both Gamma-ray pulsar and radio-pulsar searches have CPU and GPU applications, supporting CUDA, OpenCL, Linux, Windows, Mac OS… everything.

    GPU applications are of course the fastest and most powerful. FP32 or single precision is used only, so even consumer graphic cards designed for gaming will yield excellent performance. Fastest computer currently contributing to Einstein@home is equipped with 8 AMD Fiji GPUs and running 24/7, so the competition is tough :)

    Einstein@home comes with an interesting Starsphere Screensaver, showing some info about the workunit you are currently processing. The crosshair (Search Marker) represents the position in the sky which is being searched.  This marker will move from point to point as the search progresses.  

    Both your CPU and GPU are busy mining latest Proof-of-Work scheme? Don’t worry, because an Android application is also available, for radio-pulsar search. Yes, you can run Einstein@home (and mint Gridcoins in turn) even with your Android device. Obviously, your contribution will be very small compared to a modern GPU, but there are literally billions of active Android devices in the world now, so the potential for some massive computational power is clearly there. Remember, Einstein@home, BOINC (and Gridcoin) are all about distributed computing i.e. plenty of small devices working together, achieving important things in the end. Even an old Android smartphone, crunching Einstein@home only while charging, can contribute a lot of computing time over a year or two. And a collective created by thousands of smartphones can be faster than a single desktop computer, even with today’s technology.

    Full article: Gridcoin GPU mining (5): Looking at the Sky — Steemit


  • Voyager Photo of Jupiter

    A photo of Jupiter.
    Took by Voyager with VGISS on February 28, 1979 at 04:30:59.

    Detail page on OPUS database.

    http://darth-azrael.tumblr.com/post/154214185940/hellospacebot-a-photo-of-jupiter-took-by