Cosmology

Scientists have long been puzzled by the difference in topography between different sides of the moon, with the near side being flat and the far side much more mountainous.

Now astronomers believe that the moon was struck by a huge object in a ‘big splat’, which gave our solar companion its giant peaks and coated one side of it with a crust tens of kilometres thick.…

…The problem, the scientists report Monday in Nature, is that while the tiny galaxy dates from just 700 million years or so after the big bang, it's far more dusty than something this young and small has any right to be. …

"Goddard Space Flight Center just released this collection of images from the SDO mission on it’s fifth anniversary." [Video at link]

The outer reaches of our solar system may have been shaped long ago by a close encounter with another star that tore up both nascent planetary systems like colliding buzz saws, astronomers said today.
The dramatic encounter, if it occurred, might even have deposited an alien world into our midst.
 The scenario was devised to describe unexplained observations of the solar system but is based on speculation about actual events. The resulting computer simulations suggest a range [of] possible outcomes for a close celestial brush shortly after the planets formed, about 4.5 billion years ago.

[4,500,000,000 years ago the enormous Angona system began its approach to the neighborhood of this solitary sun. The center of this great system was a dark giant of space, solid, highly charged, and possessing tremendous gravity pull. -Urantia Paper 57 (1934)]

The most powerful sky-scanning camera yet built has begun its quest to pin down the mysterious stuff that makes up nearly three-quarters of our Universe.

The Dark Energy Survey's 570-million-pixel camera will scan some 300 million galaxies in the coming five years.

The goal is to discover the nature of dark energy, which is theorised to be responsible for the ever-faster expansion of the Universe.

"I think the F ring is Saturn's weirdest ring, and these latest Cassini results go to show how the F ring is even more dynamic than we ever thought," Carl Murray, a Cassini imaging team member based at London's Queen Mary University, said in a statement. "These findings show us that the F ring region is like a bustling zoo of objects from a half mile in size to moons like Prometheus a hundred miles in size, creating a spectacular show." The F ring is held in check by two tiny moons, Prometheus and Pandora, which weave inside and outside the outer ring. Sometimes these moons perturb the ring, creating channels and snowballs. Now scientists think that some of these snowballs survive to become the weird objects punching new holes in the ring. [Video here, after commercial]

The Moon's highlands, long a mystery, may have been thrown up billions of years ago by a slow-motion collision with a smaller companion moon knocked off its orbit.... At least one such mini-moon, about a third the diameter of the one we see today, could have been suspended between the gravitational pulls of the Moon and Earth for tens of millions of years, they calculated. Eventually, however, it would have lost its moorings and crashed into the Moon.... "According to our simulations, a large 'moon-to-Moon' size ratio and a subsonic impact velocity lead to an accretionary pile rather than a crater," Jutzi and Asphaug concluded. This scenario would also help explain why the farside's crust is so much thicker, and why certain minerals are concentrated there

Spirit has been incommunicado for more than a year despite daily calls by NASA. The cause of Spirit's silence may never be known, but it's likely the bitter Martian winter damaged its electronics, preventing the six-wheel rover from waking up. The space agency tried every trick to listen for Spirit to no avail. Project manager John Callas of NASA's Jet Propulsion Laboratory said the last commands will be sent up Wednesday. Though orbiting spacecraft will continue to listen through the end of May, chances are slim that Spirit will respond.

Japanese astronomers claim to have found free-floating "planets" which do not seem to orbit a star. Writing in Nature, they say they have found 10 Jupiter-sized objects which they could not connect to any solar system. They also believe such objects could be as common as stars are throughout the Milky Way.

NASA's Messenger probe is set to make history tomorrow night (March 17) when it becomes the first spacecraft ever to enter into orbit around the planet Mercury. …will map Mercury's surface in detail, as well as investigate the planet's composition, magnetic environment and tenuous atmosphere, among other features.

Huge geysers on Saturn's moon Enceladus may be fed by a salty sea below its surface, boosting the odds of extraterrestrial life in our own Solar System

first-ever comprehensive computer model of sunspots. The resulting visuals capture both scientific detail and remarkable beauty.