← Another date

Birthday · October 6, 2014

Space Station Detector Finds Unexplained Positron Excess

October 6, 2014

The cosmos is full of spectacular things: ringed planets, exploding suns, rivers of stars across the night.

Space Station Detector Finds Unexplained Positron Excess

A little universe, just for you

Your date.
Ready to give.

Free PNG · 1080 × 1350 · No account needed

Image rights and credit requirements apply when sharing or reusing imagery.

Change the year

APOD published October 6, 2014. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

Behind the image

Space Station Detector Finds Unexplained Positron Excess

Original APOD · October 6, 2014

Where did all these high energy positrons come from? The Alpha Magnetic Spectrometer (AMS-02) onboard the International Space Station (ISS) has been meticulously recording how often it is struck by both high energy electrons and positrons since 2011. After accumulating years of data, it has now become clear that there are significantly more positrons than expected at the highest energies detected. The excess may have a very exciting and profound origin -- the annihilation of distant but previously undetected dark matter particles. However, it is also possible that astronomical sources such as pulsars are creating the unexplained discrepancy. The topic remains a very active area of research. Pictured here, the AMS is visible on the ISS just after being installed, with a US Space Shuttle docked on the far right, a Russian Soyuz capsule docked on the far left, and the blue Earth that houses all nations visible across the background. Follow APOD on: Facebook, Google Plus, or Twitter

Explore October 6 in other years