An extraordinary collection of ancient feather fragments preserved in amber has opened a window into a lost world, one that now appears populated by dinosaurs covered in plumage as rich and varied as that of modern birds.
The feathers date to the end of the Cretaceous, about 85 to 70 million years ago. At that time, the forerunners of birds were well on their way to taking wing; dinosaurs like Epidexipteryx and Limosaurus, discovered in China in the last decade and dating to approximately 160 million years ago, possess relatively bird-like bone structures and hints of what might have been feathers.
Those hints have been interpreted — and given life in eye-popping artist renditions — as feathers, an interpretation that was plausible but still inconclusive.
“These lovely specimens of significantly older, smaller dinosaurs from China have got some sort of covering about them. But you can’t tell if it’s hair or feathers because the fossils have undergone the ravages of time,” said paleontologist Alex Wolfe of the University of Alberta, a co-author of the new study. “Those fossils don’t preserve the kind of detail that we have in amber, which doesn’t fossilize but entombs an object.”
Moon Satellite Gives New Glimpse of Lunar North Pole
NASA has combined nearly 1,000 photos of the moon to build the crispest view yet of the crater-pocked lunar north pole.
The space agency created the new image by stitching together slices of 983 wide-angle photographstaken by a camera on the Lunar Reconnaissance Orbiter, or LRO. The image contains a psychedelic spiral in the center because the LRO collected the images from different angles over the course of a month.
A prime goal of the $583 million moon-orbiting mission is to hunt for water ice and other useful materials that may help future human explorers establish a permanent base. Just as LRO found evidence of water ice in south pole craters untouched by the sun, it may also exist in shadowed north pole craters.
To that end, LRO in August 2009 sent a probe called LCROSS into a permanently shadowed crater near the lunar south pole. (Water may exist in a frozen state near the surface of such regions because no sunlight touches them.)
The new view of the lunar north pole joins a lineage of maps compiled by spacecraft such as Galileo andClementine. LRO has the most detailed view of the moon to date, and has photographed lunar mountains, strange spirals and even the tiny traces left by Apollo astronauts, their lunar buggies, instruments and spacecraft.
Image: NASA/GSFC/Arizona State University
A white hole, in general relativity, is a hypothetical region of spacetime which cannot be entered from the outside, but from which matter and light may escape. In this sense it is the reverse of a black hole, which can be entered from the outside, but from which nothing, including light, may escape. (However, it is theoretically possible for a traveler to enter a rotating black hole, avoid the singularity, and travel into a rotating white hole which allows the traveler to escape into another universe.)
Like black holes, white holes have properties like mass, charge, and angular momentum. They attract matter like any other mass, but objects falling towards a white hole would never actually reach the white hole’s event horizon.
See also; Event Horizons
Abell 39, about 7000 light years away, is a ghostly remnant of a Sun-like star and one of the largest existing spheres in the Milky Way. Six light-years across, it was once a sun-like star’s outer atmosphere expelled thousands of years ago. The nearly perfect spherical nature of Abell 39 allows astronomers to accurately estimate how much relative material is actually absorbing and emitting light.
Observations indicate that Abell 39 contains only about half of the oxygen found in the Sun, an intriguing but not surprising confirmation of the chemical differences between stars. The reason why the central star is slightly off center by 0.1 light-years is currently unknown. Several galaxies millions of light years away can be seen through and around the spectral nebula.
Kepler confirms its first planet in habitable zone of Sun-like star
This diagram compares our own solar system to Kepler-22, a star system containing the first “habitable zone” planet discovered by NASA’s Kepler mission.
Thistle Mantis Nymphs, Israel
Photo: Erez Marom
Two thistle mantis nymphs are captured up close at Rishon Lake in Israel.
In 1997, Comet Hale-Bopp delighted observers across the globe with its well-defined dust and gas tails. In this photo, the two tails nicely frame the North America Nebula in Cygnus.
Photo by Tony Hallas
The Propeller Nebula (DWB 111) in Cygnus
Taken through LB-0003: 14.5-inch (0.37-meter) RC Optical Systems Ritchey-Chretien reflector with ion-milled optics at f/9.0 on a Software Bisque Paramount ME German Equatorial mount, Apogee Alta U16M CCD camera, Hydrogen-alpha/Sulfur-II/Oxygen-III image with exposures of 90, 60, and 60 minutes, respectively
Photo by John Ebersole