Space

One of the most fascinating nearby planetary systems, 55 Cancri, is now less mysterious.

Hopefully. The authors say theirs is the first viable model for  the planetary system of 55 Cancri, one the first stars discovered to have planets.

Numerous studies since 2002 had failed to determine a plausible model for the masses and orbits of two giant planets located closer to 55 Cancri than Mercury is to our Sun. Astronomers had struggled to understand how these massive planets orbiting so close to their star could avoid a catastrophe such as one planet being flung into the star, or the two planets colliding with each other.

A newly discovered "hypervelocity star" is the closest, second-brightest and among the largest found so far. It is speeding at more than 1 million mph and may provide clues about the supermassive black hole at the center of our Milky Way. Also, add in the obligatory "dark matter" reference.

Hypervelocity stars appear to be remaining pairs of binary stars that once orbited each other and got too close to the supermassive black hole at the galaxy's center. Intense gravity from the black hole – which has the mass of 4 million stars like our sun – captures one star so it orbits the hole closely, and slingshots the other on a trajectory headed beyond the galaxy.


Astronomers have made a measurement of a distant neutron star that is one million times more precise than the previous world's best - and they did it by using...nothing.

The interstellar medium is the 'empty' space between stars and galaxies. It's not really empty, it is made up of sparsely spread charged particles and those can be used as a giant lens. The astronomers did just that, to magnify and look closely at the radio wave emission from a small rotating neutron star.

Result: the highest resolution measurement ever achieved, equivalent to being able to see the double-helix structure of our genes from the Moon.


One of the most powerful events in our universe – Gamma-Ray Bursts (GRB) – behave differently than previously thought, and this evidence from observation of a GRB rules out most of the existing hypothetical predictions concerning the afterglow of the explosions.


Astronomers have taken unprecedented images of the intergalactic medium (IGM) — the diffuse gas that connects galaxies throughout the universe — with the Cosmic Web Imager, which was designed and built at the California Institute of Technology.

Until now, the structure of the IGM has mostly been a matterof speculation, but with observations from the Cosmic Web Imager, deployed on the Hale 200-inch telescope at Palomar Observatory, astronomers are obtaining our first three-dimensional pictures of the IGM.

The Cosmic Web Imager will make possible a new understanding of galactic and intergalactic dynamics, and it has already detected one possible spiral-galaxy-in-the-making that is three times the size of our Milky Way.


A team of researchers led by Robert Quimby at the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) has announced the discovery of a galaxy that magnified a background, Type Ia supernova thirtyfold through gravitational lensing. This is the first example of strong gravitational lensing of a supernova confirms the team's previous explanation for the unusual properties of this supernova. 


A "brown dwarf" star with the catchy name of  WISE J085510.83-071442.5 appears to be the coldest of its kind.

When people think of stars, they think of hot fusion plasma bubbling and erupting.  WISE J085510.83-071442.5,  7.2 light-years away, making it the fourth closest system to our sun, is instead as frosty as Earth's North Pole.



The locations of the star systems that are closest to the Sun.
The year when each star was discovered to be a neighbor of  the
Sun is indicated. The brown dwarf WISE J085510.83-071442.5
is the fourth nearest system to the Sun. Credit: Janella Williams,


The southern hemisphere of Mars is home to a crater that contains very well-preserved gullies and debris flow deposits and he geomorphological attributes of these landforms provide evidence that they were formed by the action of liquid water in geologically recent time.


A meteor caught on film during its non-luminous free fall at terminal velocity ? Or an elaborate hoax ? Or something else ? I must admit that when I saw the video posted in the internet a few weeks ago I was intrigued, and operated a willful suppression of disbelief. The footage showed a free-falling black stone that really looked like a meteoroid, passing by the owner of the camera hanging on a parachute, on the skies of Norway. I wanted to believe!


Above: sum of frames from the video shot by the parachuters

What looked at first like a sort of upside-down planet in
the binary star system KOI-3278
has instead revealed a new method for studying binary star systems, according to a University of Washington team who writes of the first "self-lensing" binary star system — one in which the mass of the closer star can be measured by how powerfully it magnifies light from its more distant companion star.

Our sun stands alone but about 40 percent of similar stars are in binary (two-star) or multi-star systems, orbiting their companions in a gravitational dance.