TODAY IN HISTORY: Remembering the crew of the Space Shuttle Columbia mission STS-107, killed on February 1, 2003 when the orbiter disintegrated as it reentered the Earth’s atmosphere: Ilan Ramon, payload specialist; William C. McCool, pilot; David M. Brown, mission specialist; Kalpana Chawla, mission specialist; Michael P. Anderson, payload commander; Laurel B. Clark, mission specialist; and Rick D. Husband, mission commander. (NASA)
“Detecting this signal is possible if we are able to monitor a sufficiently large number of pulsars spread across the sky,” said Stephen Taylor, lead author of the paper published this week in The Astrophysical Journal Letters. He is a postdoctoral researcher at NASA’s Jet Propulsion Laboratory, Pasadena, California. “The smoking gun will be seeing the same pattern of deviations in all of them."
An international research team including scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany used a combination of radio and optical telescopes to identify the precise location of a fast radio burst (FRB) in a distant galaxy, allowing them to conduct a unique census of the Universe’s matter content.
Their result, published in today’s edition of Nature, confirms current cosmological models of the distribution of matter in the Universe.
another of what seem to be rare photos of SOVIET SPACE LASER BATTLE STATION POLYUS, intended to destroy (then-notional) western armed satellites, but failed to make orbit
Comets are known to be a mixture of dust and ice, and if fully compact, they would be heavier than water. However, previous measurements have shown that some of them have extremely low densities, much lower than that of water ice. The low density implies that comets must be highly porous.
But is the porosity because of huge empty caves in the comet’s interior or it is a more homogeneous low-density structure?
In a new study, published in this week’s issue of the journal Nature, a team led by Martin Pätzold, from Rheinische Institut für Umweltforschung an der Universität zu Köln, Germany, have shown that Comet 67P/Churyumov-Gerasimenko is also a low-density object, but they have also been able to rule out a cavernous interior.
This result is consistent with earlier results from Rosetta’s CONSERT radar experiment showing that the double-lobed comet’s ‘head’ is fairly homogenous on spatial scales of a few tens of metres.
The A-object moves in a 97.5 degree inclined, 465 x 502 km sun-synchronous polar orbit with an orbital period of 94.3 minutes. The satellite makes daily morning passes around ~9h am. It has a repeating ground-track every 4th day. This is consistent with a remote-sensing role.
The orbit is somewhat lower and more circular than that of North Korea’s previous satellite, KMS 3-2, which was initially placed in a 495 x 588 km orbit. Like the 2012 launch, North Korea had to perform a dogleg manoeuvre to attain an orbital inclination of 97.5 degrees after launching due south from Sohae (see discussion in my previous post).
Dwarf planet Ceres is the largest object in the Solar System’s main asteroid belt, with a diameter of about 950 kilometers (590 miles). Ceres is seen here in approximately true color, based on image data from the Dawn spacecraft recorded on May 4, 2015. On that date, Dawn’s orbit stood 13,642 kilometers above the surface of the small world. Two of Ceres’ famous mysterious bright spots at Oxo crater and Haulani crater are near center and center right of this view. Casting a telltale shadow at the bottom is Ceres’ cone-shaped, lonely mountain Ahuna Mons. Presently some 385 kilometers above the Cerean surface, the ion-propelled Dawn spacecraft is now returning images from its closest mapping orbit.
(source)
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