Counting Sand Grains 

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Identifying the source of perytons at the Parkes radio telescope

Identifying the source of perytons at the Parkes radio telescope
by E. Petroff, E. F. Keane, E. D. Barr, et al.
http://arxiv.org/abs/1504.02165

"Perytons" are millisecond-duration transients of terrestrial origin, whose frequency-swept emission mimics the dispersion of an astrophysical pulse that has propagated through tenuous cold plasma. In fact, their similarity to FRB 010724 had previously cast a shadow over the interpretation of "fast radio bursts," which otherwise appear to be of extragalactic origin. Until now, the physical origin of the dispersion-mimicking perytons had remained a mystery. We have identified strong out-of-band emission at 2.3--2.5 GHz associated with several peryton events. Subsequent tests revealed that a peryton can be generated at 1.4 GHz when a microwave oven door is opened prematurely and the telescope is at an appropriate relative angle. Radio emission escaping from microwave ovens during the magnetron shut-down phase neatly explain all of the observed properties of the peryton signals. Now that the peryton source has been identified, we furthermore demonstrate that the microwaves on site could not have caused FRB 010724. This and other distinct observational differences show that FRBs are excellent candidates for genuine extragalactic transients. Read More »

The Rothschild Libel: Why has it taken 200 years for an anti-Semitic slur that emerged from the Battle of Waterloo to be dismissed?

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The Rothschild Libel: Why has it taken 200 years for an anti-Semitic slur that emerged from the Battle of Waterloo to be dismissed?
Thirty years after the dust had settled on the fields of Waterloo, a poisonous anti-Semitic pamphlet circulated in Europe, claiming the Rothschild family had accrued its vast wealth on the back of Wellington's triumph. The 'facts' were entirely made up.
by Brian Cathcart, The Independent, 03 May 2015.

MESSENGER's Final Image

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MESSENGER's Final Image
Release Date: April 30, 2015
Image Mission Elapsed Time (MET): 72716050
Image ID: 8422953
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 72.0°
Center Longitude: 223.8° E
Resolution: 2.1 meters/pixel
Scale: This image is about 1 kilometers (0.6 miles) across
Incidence Angle: 57.9°
Emission Angle: 56.5°
Phase Angle: 40.7°

Of Interest: Today, the MESSENGER spacecraft sent its final image.

Originally planned to orbit Mercury for one year, the mission exceeded all expectations, lasting for over four years and acquiring extensive datasets with its seven scientific instruments and radio science investigation. This afternoon, the spacecraft succumbed to the pull of solar gravity and impacted Mercury's surface. The image shown here is the last one acquired and transmitted back to Earth by the mission. The image is located within the floor of the 93-kilometer-diameter crater Jokai. The spacecraft struck the planet just north of Shakespeare basin. Read More »

Early quantum chromodynamic quark model from the Ripley Scrowle, mid 15th century.

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Early quantum chromodynamic quark model from the Ripley Scrowle, mid 15th century.


Metaphysische Träume in Gottes Villa Kunterbunt
Drei Anmerkungen zur Utopie einer Weltformel nach der Entdeckung des Higgs-Bosons
by Ulrich Kühne (Neue Zürcher Zeitung, ed. 14. July 2012, p.22)

Wenn das Higgs-Boson das „Gottesteilchen“ ist, dann hat Gott letzte Woche die vielleicht letzte große Chance vertan, das von uns fehlbaren Menschen mehr schlecht als recht zusammengeschusterte Standardmodell der Teilchenphysik zu widerlegen. Dass bei den Physikern „resignierte Erschöpfung“ bemerkbar sei, kommentierte denn auch Stephen Wolfram, der schon 1974 als 15-Jähriger wichtige Beiträge zum Standardmodell veröffentlicht hat, die Stimmung auf der Pressekonferenz im CERN-Forschungszentrum, wo der erfolgreiche Nachweis dieses letzten fehlenden, theoretisch vorhergesagten Bausteins des Universums bekannt gegeben wurde. Wie die meisten großen Theoretiker hätte Wolfram es lieber gesehen, wenn die Experimente in Genf etwas Neues und völlig Unerwartetes gezeigt hätten – etwas, das der Hoffnung neue Nahrung gegeben hätte, dass die Wahrheit über das Universum doch schöner und tiefsinniger ist, als das Standardmodell befürchten lässt. Read More »