Kategorie: Asteroiden & Co.

Asteroid 1999 KW4 was first discovered by astronomers in 1999. When it got closer, in 2001, astronomers realized it wasn’t a single asteroid, but two clusters of rubble orbiting each other. It’s been classified as a Potentially Hazardous Asteroid, but astronomers have calculated a safe trajectory out for at least 1.000 years. Since it’s a binary object, astronomers are able to calculate the mass and density of the two asteroids. New observations from the Arecibo Observatory have mapped the twin objects in tremendous detail.
Observations of double asteroid stress Arecibo radar’s vital role in identifying threats in Earth’s vicinity

Radar Imaging of Binary Near-Earth Asteroid (66391) 1999 KW4

Dynamical Configuration of Binary Near-Earth Asteroid (66391) 1999 KW4

The surviving portion of the Deep Impact space probe that watched its „impactor’s“ collision with comet Tempel 1 on July 4, 2005, is being sent on a mission to study another comet. NASA announced Tuesday that it has accepted a proposal by the University of Maryland, which developed and manages Deep Impact, to send the vehicle on an extended mission to intercept Comet Boethin. The new mission will not involve a collision. Instead, Deep Impact will pass Boethin in December 2008 so its instruments can examine the comet. The spacecraft remains healthy and researchers are hoping to gather information from Boethin that will help to understand further of how comets formed and evolved and if they played a role in the emergence of life on Earth.

Deep Impact Legacy Site

A fire that destroyed a cottage near Bonn and injured a 77-year-old man was probably caused by a meteor and witnesses saw an arc of blazing light in the sky, German police said on Friday. Burkhard Rick, a spokesman for the police in Siegburg east of Bonn, said the fire gutted the cottage and badly burned the man’s hands and face in the incident on October 10. „We sought assistance from Bochum observatory and they noted that at that particular moment the earth was near a field of meteoroid splinter and it could be assumed that particles had entered the atmosphere“, he said. „The particles usually don’t reach the surface because they disintegrate in the atmosphere“, he added. „But some can make it to the ground. We believe this was a bolide (meteoric fireball) with a size of no more than 10 mm.“
Source: Reuters

A house burns down „mysteriously“, and suddenly an extraterrestrial cause is invoked with no evidence whatsoever? Sorry, but this sounds pretty bogus to me. Only if this is substantiated with evidence of impact damage to the house prior to the fire, or meteorite debris recovered from the ruins, I’ll retract my scepticism. Btw. a 10 mm fragment wouldn’t reach the ground…

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)

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

The surface of the solar system’s largest asteroid, Ceres, has been mapped in infrared light in fine detail for the first time. The feat will pave the way for a better determination of the surface composition of Ceres, whose interior is believed to be 25% water ice. The 950-kilometre-wide space rock lies in the main asteroid belt between Mars and Jupiter and is massive enough for its gravity to make it a sphere, a quality that nearly earned it planetary status in August 2006. The Hubble Space Telescope took visible light images of Ceres in 2003 and 2004 and also mapped the asteroid in ultraviolet light in 2001. These images show bright and dark patches on the asteroid, but astronomers still do not know exactly what the patches represent. Now astronomers led by Benoit Carry of the Paris-Meuden Observatory in France have taken a step towards solving the mystery by obtaining the first high-resolution images of Ceres in infrared light, which is better than visible or UV light at distinguishing chemicals. They used the Keck II telescope atop Mauna Kea in Hawaii to obtain the images, which show features as small as 30 kilometres across. The infrared images show bright and dark patches that closely match what Hubble saw in visible light.
Source:
Surface mapping of asteroid Ceres with the Keck AO system
Carry, B., Dumas, C., Fulchignoni, M., Merline, W.
Presented at the 38th Annual Meeting of the Division for Planetary Sciences in Pasadena, California, October 8-13, 2006.
Images of Dwarf Planet Ceres