The dark energy

What lies at the heart of modern physics – a kind of cosmic hole in the room. Physicists realise that when we look out 13.7 billion light years across the visible universe with our telescopes – whether at visible, infrared, gamma ray or x-ray wavelengths, we are only seeing a tiny proportion of all that there is.

What lies at the heart of modern physics – a kind of cosmic hole in the room. Physicists realise that when we look out 13.7 billion light years across the visible universe with our telescopes – whether at visible, infrared, gamma ray or x-ray wavelengths, we are only seeing a tiny proportion of all that there is.
Modern physics and its key theories of Newtonian and quantum mechanics and general relativity, which has successfully provided us with everything from iPods to GPS systems simply doesn’t have a clue as to what makes up 96% of the universe.The best estimates of cosmologists and physicists reveal that the universe is constituted of 4% of normal baryonic matter, consisting of the things we see with our eyes and detectors. This is made of atoms and their constituent parts – and includes stars, planets and intergalactic dust. Einstein said that mass and energy are equivalent, and since the late 1990s astronomers and cosmologists have found that a staggering 73% of the universe is made of something called Dark Energy, which reveals itself and an anti-gravitational force. The expanding universe it turns out, as first revealed by Edwin Hubble isn’t just expanding at a linear rate, the expansion is accelerating.
We may have rather more success in identifying Dark Matter, first postulated by astronomer Fritz Zwicky in 1934, to account for evidence of “missing mass” in the orbital velocities of galaxies in clusters. It is believed that most Dark Matter, by its very nature does not consist of atoms, it doesn’t interact with electromagnetic radiation, and therefore we cannot detect it with our telescopes. There are many possibilities as to what Dark Matter may be, and these include:- Normal matter which has so far eluded our gaze, such as dark galaxies, brown dwarfs, planetary material (rock, dust, etc.), or black holes. Some of these could be MACHOs (Massive Astrophysical Compact Halo Objects), which would explain the distribution of Dark Matter in galaxy halos.- Massive standard model neutrinos.- Massive exotica. These can be divided into two possible classes, the first consisting of either axions (a hypothetical elementary particle), additional neutrinos, supersymmetric particles, or a host of others. Their properties are constrained by the theory which predicts them, but by virtue of their mass, they solve the dark matter problem if they exist in the correct abundance.

The twin Voyager spacecraft were launched in August and September of 1977 on board a Titan IIIE/Centaur boosters. Their missions, which they executed perfectly were to explore the giant outer planets, Jupiter, Saturn, Neptune and Uranus. Thirty three years later and billions of miles from Earth, it is pleasing to report that both craft are once again healthy and are sending data back daily.  From locations where the influence of our Sun finally runs out, these little robotic emissaries from Earth have finally become interstellar travellers. NASA engineers have fully revived the far-flung Voyager 2 probe on the edge of the solar system after fixing a computer glitch that scrambled its messages home for nearly three weeks. A single bit flip in one location in the 33-year-old probe’s memory storage caused the problem, and was remotely reset Sunday by engineers at NASA’s Jet Propulsion Laboratory in Pasadena, California. After a computer reset, the Voyager 2 is back on track, they said.The malfunction began April 22 while Voyager 2 was flying 8.6 billion miles (13.8 billion km) from Earth in the heliosphere, the magnetic bubble that surrounds our solar system. Mission scientists could not decipher the probe’s science data messages and put the spacecraft in an engineering mode to just send health updates to Earth.The actual cause of the computer glitch is still unknown, NASA’s Voyager 2 project manager Ed Massey said. Memory bit flips and other electronic problems have affected spacecraft, and even Voyager 2 and its twin Voyager 1, in the past. But they occurred when the spacecraft were much closer to Earth, around 1 or 2 astronomical units (AU). One AU is the distance between the Earth and the sun, about 93 million miles (151 million km). That’s close enough for their onboard systems to be affected by the electric charge of the sun’s solar wind, Massey said.In some spacecraft that are closer to the sun one could think of single event upsets caused by solar activity. But we’re so far away, it’s hard to say that’s what caused it,” he added. “We’re like 93, 94 AU out.”  The two Voyager probes are currently the farthest human-built objects from Earth. Voyager 1 is about 10.5 billion miles (16.9 billion km) away from Earth and in perfect health.

ozily positioned next to the piping hot kettle corn tent and across from the Panasonic HD 3D truck, NASA’s new traveling exhibit “From Rockets to Race Cars” made its NASCAR debut last weekend at Richmond International Raceway. From better brakes and safer tires, the exhibit features NASA’s contributions to the racing world, a correlation that was news to a lot of people.

The Wheel Exhibit, which included a NASCAR tire, a Shuttle tire, replica of a Lunar Rover tire, a Lunar Tweel and a Spring Tire, was a major hit. Race fans took pictures in front of them and learned that NASA technology has resulted in stronger, safer tires for drivers.

“From Rockets to Race Cars” will continue along the racing circuit making stops at Charlotte Motor Speedway, May 29-30 and at the Kentucky Speedway, June 11-12.

Boat owners now have a better idea of the amount and purity of their fuel thanks to a NASA-developed wireless sensor technology.

Originally developed at NASA’s Langley Research Center in Hampton, Va., to retrofit aging aircraft with vehicle safety monitoring equipment, the technology is a spinoff for designing and using sensors without the shortcomings of many commonly used measurement systems.

Traditional marine fuel-gauge float systems can experience inaccurate readings due to movement; a boat’s pitch and roll in open waters can create a “seesaw” effect on fuel gauges. But the wireless fluid-level measurement system has two stationary pieces of conducting material in the fuel connected to an inductor on the outside of the tank.

Another important aspect of the wireless fuel-level sensor system and a major concern for boaters in a marine environment is that its design can be modified to detect water — similar to a commercial version of the sensor. It can also be modified to detect other non-fuel liquid contaminants in the tank.

Saturn’s largest moon, Titan, is perhaps best know for its unique, hazy atmosphere and lakes of liquid methane.
But a new look at Titan’s insides reveals even more oddities: Beneath the brittle crust of ice lies a layer of slush. Deeper still is an underground ocean over a solid core of rock and ice.
Until now, scientists had thought Titan’s interior would look a lot like the inside of Jupiter’s moon Ganymede: Both bodies are large, have similar densities, and are made of roughly the same materials.

Under Ganymede’s thin, icy crust lies a well-defined upper mantle of warmer ice, an inner mantle of silicate, and a molten iron core.
But the new gravity data suggest that Titan and Ganymede had very different evolutionary histories.
The study’s calculations support the idea that Titan today has a subsurface liquid ocean from which methane bubbles up through an icy crust, constantly shrouding Titan in thick smog.
The study’s notion of a relatively warm, spongy ice layer beneath a thin, hard outer shell would also explain Titan’s lack of major mountains.Large mountains can’t exist on Titan because they would simply sink into the ice.

Recently NASA crashed two spacecraft into the moon and orbiters scanned the lunar surface for telltale light signatures—all to confirm the rocky body isn’t bone dry after all.
Tiny amounts of water have been found in some of the famous moon rocks brought back to Earth by the Apollo astronauts. The water levels detected in Apollo moon rocks and volcanic glasses are in the thousands of parts per million, at most—which explains why analyses of the samples in the late 1960s and early 1970s concluded that the moon was absolutely arid.
The finding is “one of the first to detect water in a lunar magmatic mineral” and adds to evidence that moon magma, in general, contains trace amounts of water, according to geoscientist Francis McCubbin, who participated in the research.
Where’s Moon Water From?
Going forward, the researchers plan to investigate how water ended up in the moon. The most common guesses center on the moon’s earliest days, shortly after it had been created by the collision of a Mars-size object with Earth.
One possibility, according to Wesleyan’s Greenwood, is that icy comets hit the molten young moon as it was still solidifying.
Another possibility, said the Carnegie Institution’s McCubbin, is that not quite all the water was driven off when chunks of Earth were flung spaceward to form the moon—in other words, the water may be from an ancient version Earth.

The view from space has always had the “wow” factor. Now thanks to the bay window-like cupola attached to the new Tranquility node, the International Space Station has a panoramic view that takes the wow factor to the max.

The STS-130 astronauts delivered the two new space station pieces, the final components of the U.S. segment of the station, aboard space shuttle Endeavour during the first mission of the year
The assembled crew consisted of Commander George Zamka, Pilot Terry Virts, and Mission Specialists Robert Behnken, Nicholas Patrick, Kathryn Hire and Stephen Robinson. All but Virts were veterans of previous spaceflights.

During their final trip outside the station, spacewalkers Patrick and Behnken prepared cupola’s window covers to be opened for the first time, and finished exterior work on Tranquility and the relocated docking port.

As he opened the window covers one by one, Virts became the first crew member to take in the breathtaking view that the cupola now provides, with Patrick and Behnken on the outside looking in. The observation dome’s seven windows facing Earth will greatly improve views for robotic and docking activities at the station, as well as provide scientific observations of Earth and celestial bodies.

As part of cupola’s dedication ceremony, a moon rock from the Apollo 11 mission was placed inside. The same rock was carried to the summit of Mount Everest by astronaut Scott Parazynski.

The crew members took time to receive a congratulatory phone call from President Barack Obama near the end of Endeavour’s time docked to the station. The president was accompanied at the White House by a dozen middle school students from across the country who were in the nation’s capital for an engineering competition.

Picture yourself outside on a clear dark night. Low on the horizon you notice a faint glow of greenish light which forms an arch, stretching lazily across the sky. As time passes, additional bands of light form and drift overhead, slowly brightening to form giant curtains in the sky that slowly wave as if a gentle breeze were blowing. Suddenly, the bottom of the curtains brighten with a reddish tint and ripple faster. Blues and purples appear. As the curtains pass directly overhead, you see bright points of light that swirl like a pinwheel. The entire sky seems to be full of color and motion. Then, after several minutes, everything fades into a warm green glow.
The short answer to how the aurora happens is that energetic electrically charged particles (mostly electrons) accelerate along the magnetic field lines into the upper atmosphere, where they collide with gas atoms, causing the atoms to give off light.

Auroras can be spotted throughout the world and on other planets. It is most visible closer to the poles due to the longer periods of darkness and the magnetic field.
Auroras are associated with the solar wind, a flow of ions continuously flowing outward from the sun. The Earth’s magnetic field traps these particles, many of which travel toward the poles where they are accelerated toward earth. Collisions between these ions and atmospheric atoms and molecules causes energy releases in the form of auroras appearing in large circles around the poles. Auroras are more frequent and brighter during the intense phase of the solar cycle when coronal mass ejections increase the intensity of the solar wind.Seen from space, these fiery curtains form a thin ring in the shape of a monk’s tonsure.

The first and most beautiful solar eclipse of the decade worded the ‘Ring of fire’ occurred on 15 January, 2010. This marvelous event is also known as annular eclipse, because a bright annulus or ring of sun light remains visible even when the moon is directly between Earth and Sun.
The moon’s orbit is not circular so the distance between Earth and moon is not same always. During an annular eclipse the moon is farthest away from earth hence its size is smaller than the visible disc of the sun.
This day’s annular eclipse first appeared over Africa swept over Indian Ocean ended visibly in the eastern part of the world. Evidently the longest eclipse lasting an incredible 11 minutes and 7 seconds.
In my neighborhood many availed the special glasses to view this spectacular phenomenon. Eager people who couldn’t get the glasses made use of X-rays and window glass panes so they don’t miss the event