Numerous feathered dinosaur specimens have recently been recovered from the Middle–Upper Jurassic and Lower Cretaceous deposits of northeastern China, but most of them represent small animals1
shares some features, particularly of the cranium, with derived tyrannosauroids2
The Lyrid meteor shower will be best seen in the early morning hours of April 22nd. Under a dark sky, you can expect to see up to 20 bright meteors per hour.
Evening Planets
In early April, four planets grace the sky at nightfall
In the west, Jupiter hangs low on the horizon. Around mid-month, the planet disappears into the sunset
Venus blazes just above Jupiter in the west. Use a telescope to see its crescent phase.
In the south, Mars is already climbing high. It will remain visible into the early morning
Saturn will shine low in the east in the evening but climb higher during the night. On April 15th, Saturn reaches opposition, meaning it is opposite the Sun in Earth’s sky. It is also closer to Earth than it’ll be the rest of the year, making it
appear slightly bigger and brighter
Comets skimming past the sun may seem like ill-fated cosmic snowballs, and a team of scientists is trying to figure out what makes some fizzle and others explode as they make their solar death dives
shed light on the potential risks the comet deaths on the sun could pose for us on Earth
In recent decades, astronomers have witnessed even dramatic interactions between comets and the sun
researchers are analyzing how these so-called sun-diving comets lose their mass and energy depending on how close they get to the star.
Such data can show us for the first time what is inside a comet
All other data to date, apart from Jupiter impacts like Shoemaker-Levy 9, are only from the surface layers."
the sun's lower atmosphere. This lies about 4,350 miles (7,000 kilometers) above the top of the photosphere, the sun's brightest visible layer.
sunskimmer" comets — ones that dive toward the sun but not into its lower atmosphere — can slowly get vaporized by sunlight in deaths that last hundreds to thousands of seconds, depending on their mass
scientists calculated that the comets should emit weak but detectable extreme ultraviolet radiation.
sunplunger" comets that get even closer to the sun will meet their demise in only a few seconds, as they collide with the dense layers of the sun's lower atmosphere
most massive comets smashed into the sun, they would produce dramatic explosions just above the photosphere
To create their model, the scientists looked at the first direct observations of sunskimmer comets, captured last year by NASA's sun-watching Solar Dynamics Observatory (SDO).
comet, C/2011 N3, was completely destroyed after passing about 62,000 miles (100,000 km) above the photosphere
comet, Lovejoy (C/2011 W3), survived a close approach to a similar distance of 87,000 miles (140,000 km), although it lost a significant fraction of its mass in the process
Both events were in line with the predictions of the researchers' new model.
corona is hot, but its density is so small that the heat Lovejoy experienced "would be quite safe even on our skin
Comet Lovejoy did pass through the sun's million-degree corona
Comets might help serve as probes of the sun's atmosphere and magnetic field, helping to uncover its secrets
cometary flares that the very largest comets might release if they slammed into the sun can be 100 times more energetic than the largest solar flares ever observed
Such comets are, however, very, very rare today, though they may have been commoner in the early system
brought together faculty and students in astrophysics, art, and technology for a summer institute last year
team quickly settled on the idea to create an app, and also developed it into an exhibit that provides additional information and shows the app's output on a large screen
scheduled for long-term installation in the Lick Observatory visitors gallery later this month
Kepler Explorer starts with drop-down menus listing all the Kepler-discovered planetary systems, plus our own solar system
selected system is displayed in a view that shows the planet or planets in their orbits around the host star
Shown in real time the planets look motionless, but moving a slider increases the speed until the planets zip around their star
lets users zoom in and move around the system, and tapping on an individual planet brings it up for further exploration. Another view shows the relative sizes of the individual planets compared to their host star
when viewing individual planets
The user can manipulate the composition of the planet and its atmosphere and see which mixtures of components (iron, rock, water, and hydrogen) are consistent with Kepler's observations
represents graphically the type of in-depth analysis that Fortney does for the Kepler Mission
the app allows anyone to explore the properties of many different planets very quickly
only measures the radius of a planet, or how big it is. In most cases, the mass of the planet is unknown
there may be different combinations of components that result in a planet of a given size
's interactive graphics show how this works
sliders for different components and how they are partitioned in the core and the atmosphere, and as you move the sliders the image of the planet grows and shrinks, based on hundreds of calculations
the app tells you when the size of your planet matches the observations
calculations involved took hours of computer time, but the results are stored in tables so the app can use them on the fly.
A self-driving car being developed by Google Inc. took a blind man for a ride this week, driving him to a Taco Bell and then to a dry cleaner in San Jose, Calif.
Google posted a video of a modified Toyota Prius driving Steve Mahan, who is legally blind, saying it shows one of the possibilities and benefits that could come from the technology.
The self-driving car took Mahan to Taco Bell for a quick meal and a dry cleaner to pick up his clothes.
the drive took place on a carefully programmed route in San Jose and showed one of the possibilities that self-driving cars could offer.
we've now safely completed more than 200,000 miles of computer-led driving, gathering great experiences and an overwhelming number of enthusiastic supporters
From 125-million-year-old rocks, scientists have unearthed the remains of a new species of extensively feathered dinosaurs that weighed up to about 1,400 kilograms and stretched 9 meters from nose to tail.
fossils, from one adult and two younger dinos, were unearthed in northeast China
region known for keeping soft tissues of ancient animals well-preserved
Based on the shapes of the jaw and skull bones found in the fossils, the team concluded that the three animals belonged to the same species and were tyrannosaurs
broader classification of two-legged meat-eaters called theropods
biggest of the newly described creatures — the largest extensively feathered dino known to date — was about one-quarter the weight of its relative, Tyrannosaurus rex
smaller dinosaur is named Yutyrannus hauli, which translates to “beautiful feathered tyrant
new species had feathers that were at least 15 centimeters long and look as if they covered the dinosaur’s skin
might have given the dinosaur a shaggy appearance
the full extent of this covering is difficult to confirm because the specimens aren’t complete.
For the vast majority of dinosaurs we only have bone. We don’t have feathers or featherless skin
Full-feathered dinosaurs that have been discovered so far have been much smaller
much more likely to lose body heat because of their size
scientists thought these petite creatures used a fluffy layer to stay warm
study authors think that the newfound dinos might have also needed some insulation
But Norell is not convinced
Many large animals that live in warm climates, such as modern giraffes and wildebeests, have external covering but don’t need it for insulation, he says.
feathers might also have helped the dinosaurs show off and attract mates.
Other traits the new dinos had include a high, bumpy nose plate, known as a midline crest
unclear what type of posture the animals maintained, Sullivan estimates that the full-grown dino stood about 2.5 meters tall.
members have estimated that the vast majority of these candidates — 80 percent or more — will likely end up being the real deal.
artist's conception illustrates Kepler-22b, a planet known to comfortably circle in the habitable zone of a sun-like star. CREDIT: NASA/Ames/JPL-Caltech
Seeing more transits will also increase the signal-to-noise ratio for closer-in planets, allowing more of them to be detected, researchers have said
Cameron has addressed Tyson's criticism that the incorrect star field was used during one of the film's most famous scenes.
when Rose (Kate Winslet) is lying on the piece of driftwood and staring up at the stars, that is not the star field she would have seen,"
There is only one sky she should have been looking at ... and it was the wrong sky! Worse than that, it was not only the wrong sky; the left-half of the sky was a mirror reflection of the right-half of the sky
Group items tagged 
