SciByte

In 1781, English astronomer William Herschel detected Uranus in the night sky, but he thought it was a comet. It was the first planet to be discovered with the aid of a telescope. By 1787, he had also observed the Uranian satellites Titania and Oberon (11 Jan 1787), which were later given these names by his son, John Herschel.

In 1930, the discovery of a ninth planet was announced by Clyde W. Tombaugh at Lowell Observatory. It is only one-tenth as large as Earth and four thousand million miles away. The planet was named Pluto on 24 May 1930.

In 1926, the first US liquid-fuel rocket flight was launched by Robert Goddard in a field in Auburn, Mass. He thought stable flight could be obtained by mounting the rocket ahead of the fuel tank. The tank was shielded from the flame by a metal cone and was pulled behind the rocket by the lines for gasoline fuel and oxygen. The design worked, but did not produce the hoped-for stability. The rocket burned about 20 seconds before reaching sufficient thrust (or sufficiently lightening the fuel tank) for taking off. During that time it melted part of the nozzle. It took off to a height of 41-ft, leveled off and within 2.5 seconds hit the ground 184 feet away, averaging about 60 mph. The camera ran out of film, so no photographic record of that flight remains.

Located 3,600 parsecs or over 11,700 light years distant, the star is 50% larger than the famous red giant Betelgeuse

down into the center of our own solar system, and it would extend out over 6 astronomical units (A.U.s) past the orbit of Jupiter

also has a relatively small companion star orbiting across our line of sight once every 1300 days

The companion star

is also a large star in its own right at around six solar masses and 400 solar radii in size.

the surface-to-surface distance for the A and B components of the system are “only” about 2.8 A.U.s apart

This all means that these two massive stars are in physical contact, with the expanded outer atmosphere of the bloated primary contacting the secondary, giving the pair a distorted peanut shape.

yellow hypergiants are some of the brightest stars known

That’s just 16x times fainter than the apparent visual magnitude of a Full Moon but over 100 times brighter than Venus

if you placed a star like HR 5171 A 32 light years from the Earth, it would easily cast a shadow.

the discovery of a companion around such a bright star was a big surprise since any ‘normal’ star should at least be 10,000 times fainter than the hypergiant

the hypergiant was much bigger than expected

What we see is not the companion itself, but the regions gravitationally controlled and filled by the wind from the hypergiant

These latest measurements place HR 5171 A firmly in the “Top 10” for largest stars in terms of size known, as well as the largest yellow hypergiant star known

Only eight yellow hypergiants have been identified in our Milky Way galaxy

An international team of scientists

has discovered the first-ever sample of a mineral called ringwoodite

Analysis of the mineral shows it contains a significant amount of water -- 1.5 per cent of its weight

finding that confirms scientific theories about vast volumes of water trapped 410 to 660 kilometres beneath Earth's surface, between the upper and lower mantle.

This sample really provides extremely strong confirmation that there are local wet spots deep in the Earth

particular zone in the Earth, the transition zone, might have as much water as all the world's oceans put together

The diamond had been brought to the Earth's surface by a volcanic rock known as kimberlite -- the most deeply derived of all volcanic rocks.

the discovery was almost accidental in that

team had been looking for another mineral when they purchased a three-millimetre-wide, dirty-looking, commercially worthless brown diamond

The ringwoodite itself is invisible to the naked eye, buried beneath the surface, so it was fortunate that it was found

The sample underwent years of analysis using Raman and infrared spectroscopy and X-ray diffraction before it was officially confirmed as ringwoodite

one of the world's leading authorities in the study of deep Earth diamond host rocks, the discovery ranks among the most significant of his career

confirming about 50 years of theoretical and experimental work by geophysicists, seismologists and other scientists trying to understand the makeup of the Earth's interior.

Scientists have been deeply divided about the composition of the transition zone and whether it is full of water or desert-dry

Knowing water exists beneath the crust has implications for the study of volcanism and plate tectonics, affecting how rock melts, cools and shifts below the crust

This is the first study to show such long-term survival in any plant; similar timescales have only been seen before in bacteria

Mosses are

the dominant plants over large areas and are a major storer of fixed carbon

The team took cores of moss from deep in a frozen moss bank in the Antarctic

This moss would already have been at least decades old when it was first frozen

in an incubator at a normal growth temperature and light level

After only a few weeks,

the moss began to grow

Using carbon dating, the team identified the moss to be at least 1,530 years of age, and possibly even older, at the depth where the new growth was seen.

collaborators think that caenagnathids were probably omnivores

that could eat either meat or plants

studies of the rocks in which several of the most complete caenagnathid skeletons have been found show that these strata were laid down in humid floodplain environments

the other has an arthritic toe bone that may have been caused by an avulsion fracture (where a tendon ripped a piece off the bone to which it was attached).

Whether these injuries were the result of combat between two individuals or an attack by a larger predator remains a mystery

11 ½-foot-long

"It was a giant raptor, but with a chicken-like head and presumably feathers

stood about 10 feet tall

Three partial skeletons of the dinosaur – almost making up a full skeleton – were excavated from the uppermost level of the Hell Creek rock formation in North and South Dakota

The new dinosaur was 11 ½ feet long, almost 5 feet tall at the hip and weighed an estimated 440 to 660 pounds

Anzu is the largest oviraptorosaur found in North America

Oviraptorosaurs are a group of dinosaurs that are closely related to birds and often have strange, cassowary-like crests on their heads

The researchers believe Anzu, with large sharp claws, was an omnivore, eating vegetation, small animals and perhaps eggs while living on a wet floodplain

One appears to have a broken and healed rib, and the other has evidence of some sort of trauma to a toe

Like many "new" dinosaurs, Anzu wyliei fossils were discovered some years ago, and it took more time for researchers to study the fossils and write and publish a formal scientific description

This pair of images shows that material flowing down from an alcove at the head of a gully broke out of an older route and eroded a new channel

It’s unclear in what season the activity occurred because the observations took place more than a Martian year apart

These ravines tend to happen in the southern highlands and other mid-latitude regions on Mars

this type of activity generally occurs in winter, at temperatures so cold that carbon dioxide, rather than water, is likely to play the key role

The original Big Bang theory was really a theory of the aftermath of the bang

described how the universe was cooled by the expansion, and how the expansion was slowed by the attractive force of gravity

Inflation proposes that the expansion of the universe was driven by a repulsive form of gravity.

According to Newton, gravity is a purely attractive force, but this changed with Einstein and the discovery of general relativity

General relativity describes gravity as a distortion of spacetime, and allows for the possibility of repulsive gravity

Modern particle theories strongly suggest that at very high energies, there should exist forms of matter that create repulsive gravity

Inflation

proposes that at least a very small patch of the early universe was filled with this repulsive-gravity material

During the period of exponential expansion, any ordinary material would thin out, with the density diminishing to almost nothing

The repulsive-gravity material actually maintains a constant density as it expands, no matter how much it expands

While this appears to be a

violation

of the conservation of energy, it is actually

consistent

a peculiar feature of gravity: The energy of a gravitational field is negative

As the patch expands at constant density, more and more energy, in the form of matter, is created

But at the same time, more and more negative energy appears in the form of the gravitational field that is filling the region

The total energy remains constant, as it must, and therefore remains very small.

It is possible that the total energy of the entire universe is exactly zero, with the positive energy of matter completely canceled by the negative energy of gravity

At some point the inflation ends because the repulsive-gravity material becomes metastable

decays into ordinary particles, producing a very hot soup of particles that form the starting point of the conventional Big Bang

point the repulsive gravity turns off, but the region continues to expand in a coasting pattern for billions of years to come

inflation is a prequel to the era that cosmologists call the Big Bang, although it of course occurred after the origin of the universe, which is often also called the Big Bang.

Q: What is the new result announced this week, and how does it provide critical support for your theory?

The early universe, as we can see from the afterglow of the cosmic microwave background (CMB) radiation, was incredibly uniform,

to have structure form at all, there needed to be small nonuniformities at the end of inflation

The tiny nonuniformities that did exist were then amplified by gravity

these nonuniformities—which later produce stars, galaxies, and all the structure of the universe—are attributed to quantum theory

The temperature nonuniformities in the cosmic microwave background were first measured in 1992 by the COBE satellite

have not generally been seen as proof of inflation, in part because it is not clear that inflation is the only possible way that these fluctuations could have been produced.

The stretching effect of inflation,

also acts on the geometry of space itself, which according to general relativity is flexible

Space can be compressed, stretched, or even twisted.

The geometry of space also fluctuates on small scales, due to the physics of quantum theory, and inflation also stretches these fluctuations, producing gravity waves in the early universe.

The new result,

is a measurement of these gravity waves, at a very high level of confidence.

They do not see the gravity waves directly, but instead they have constructed a very detailed map of the polarization of the CMB in a patch of the sky.

They have observed a swirling pattern in the polarization (called "B modes") that can be created

by gravity waves in the early universe

This is the first time that even a hint of these primordial gravity waves has been detected

it is also the first time that any quantum properties of gravity have been directly observed.

Q: How would you describe the significance of these new findings, and your reaction to them?

The significance of these new findings

help tremendously in confirming the picture of inflation.

As far as we know, there is nothing other than inflation that can produce these gravity waves

it tells us a lot about the details of inflation that we did not already know

it determines the energy density of the universe at the time of inflation, which is something that previously had a wide range of possibilities.

By determining the energy density of the universe at the time of inflation, the new result also tells us a lot about which detailed versions of inflation are still viable, and which are no longer viable

The current result is not by itself conclusive, but it points in the direction of the very simplest inflationary models that can be constructed.

The BICEP discovery provides further indirect evidence for the existence of gravitational waves

the 1993 Nobel Prize in Physics was awarded to Russell Hulse and Joseph Taylor for finding a double pulsar that strongly supported these "ripples" in spacetime

Before this announcement

we could measure the universe back to about a minute after the Big Bang.

The finding

has allowed us to study the universe when it was a trillionth of a trillionth of a trillionth of a second old

tiny changes in temperature that were discovered by the COBE satellite (winning the 2006 Nobel Prize)

Alternative theories to inflation do not produce gravitational waves so

is strong evidence not only of the gravitational wave background but also inflation itself.

there has still been no direct detection of the gravitational radiation.

The first direct detection should follow in a few months

It is envisaged that the experiment will directly detect gravitational radiation coming from astrophysical sources from nearby galaxies