Astronomie, Raumfahrt, Space Art & mehr
The first detailed images of a binary asteroid system reveal a bizarre world where the highest points on the surface are actually the lowest, and the two asteroids dance in each other’s gravitational pull.
A binary asteroid is a system where two asteroids orbit around one another, like a mini Earth-moon system.
https://news.umich.edu/first-detailed-pictures-of-asteroid-reveal-bizarre-system/
A video is available online: kw4.mp4 (5 min 38 sec; MP4; 7.1 MB)
Mixing antimatter and matter usually has predictably violent consequences – the two annihilate one another in a fierce burst of energy. But physicists at CERN in Geneva have found a new way to make the two combine, at least briefly, into a single substance. This exceptionally unstable stuff, made of protons and antiprotons, is called protonium. The researchers believe that some of the antiprotons reacted with ionised molecules of ordinary hydrogen, stealing away a proton. These proton-antiproton systems lasted microseconds at most, but that was long enough to drift away from the core of the experiment before exploding. Protonium has been made before, but only in violent particle collisions. The new chemical method could be used to make it in much larger quantities.
Source: Physical Review Letters, vol. 97, no. 153401 (2006): Evidence For The Production Of Slow Antiprotonic Hydrogen In Vacuum
Abstract
A group of 15 scientists from five countries has discovered evidence of cell division and differentiation in fossil embryos that are more than 550 million years old. They used x-ray imaging technologies that produce higher resolutions than hospital-CT scans and digitally extracted cells from the embryos of ancient animals that have been preserved in the Doushantuo Formation, a fossil site in South China.
Virginia Tech News
Flooded rivers and more lakes have been spied on Saturn’s moon Titan in new images by the Cassini spacecraft. The features are all likely filled with liquid methane or ethane, providing insight into a methane cycle analogous to the hydrological cycle on Earth. Cassini has revealed dozens of dark areas by peering through the hazy atmosphere with its radar instrument. Previous flybys of the giant moon suggested these were lakes. The lakes seen by radar are clustered around the north polar region. They may be seasonal, accumulating at each pole from winter rains and drying up during the summer. Spring is now approaching for Titan’s northern hemisphere and some of the lakes there show indeed signs of evaporation. A lake with many lobes has been seen in the latest flyby of the moon, on October 9, 2006, suggesting it was created when a system of interconnecting rivers overflowed their banks to fill in the surrounding topography.
Lakes and More Lakes
Mars may get most of the news, but don’t forget there’s a spacecraft orbiting Venus too. New images released from ESA’s Venus Express spacecraft show new details about our twin planet’s atmosphere. These night-side infrared images reveal thermal radiation emanating from beneath the planet’s thick obscuring cloud deck. The clouds themselves are stretched out because of high-speed winds in the atmosphere.
https://www.esa.int/Science_Exploration/Space_Science/Venus_Express/Complex_meteorology_at_Venus
Although Ceres is the largest main-belt asteroid and was the first to be discovered (by G. Piazzi in 1801), its physical properties are still not well understood. While it is expected to have retained a large amount of primordial water ice in its interior, many questions about the composition of its surface and sub-surface layers, the properties of its regolith and its degree of differentiation, remain unanswered. A team of astronomers led by Benoit Carry of the Paris-Meudon Observatory used state-of-the-art adaptive optics instrumentation available at the Keck observatory, Mauna Kea, Hawaii, to image the surface of Ceres with a spatial resolution of about 30 km.
Article and Images @ Keck Observatory
A team of researchers from the Woods Hole Oceanographic Institution, the Scripps Institution of Oceanography, and the University of Massachusetts studied core samples from part of the continental shelf that was exposed during the last Ice Age. The scientists think that the land bridge between Alaska and Siberia was flooded 1.000 years earlier than previously thought.
Rapid Sea Level Rise in the Arctic Ocean May Alter Views of Human Migration
The delicate lady bug in your garden could be frighteningly large if only there was a greater concentration of oxygen in the air, a new study concludes. The study adds support to the theory that some insects were much larger during the late Paleozoic period because they had a much richer oxygen supply.
New Hubble images have provided a dramatic glimpse of a large massive galaxy under assembly as smaller galaxies merge. Hubble observations of the galaxy MRC 1138-262, nicknamed the „Spiderweb Galaxy“, have shown dozens of star-forming satellite galaxies in the actual process of merging.
https://esahubble.org/news/heic0614/
The Spitzer Space Telescope has revealed that a Jupiter-like gas giant planet circling very close to its sun is always as hot as fire on one side, and potentially as cold as ice on the other.
https://www.nasa.gov/vision/universe/starsgalaxies/spitzer-20061012.html