Into The Universe With Stephen Hawking - The Story of Everything
On August 31, 2012 a long filament of solar material that had been hovering in the sun’s atmosphere, the corona, erupted out into space at 4:36 p.m. EDT. The coronal mass ejection, or CME, traveled away from the sun at over 900 miles per second. This movie shows the ejection from a variety of viewpoints as captured by NASA’s Solar Dynamics Observatory (SDO), NASA’s Solar Terrestrial Relations Observatory (STEREO), and the joint ESA/NASA Solar Heliospheric Observatory (SOHO).
This video is public domain and can be downloaded at: :http://svs.gsfc.nasa.gov/goto?11095
The Cassini spacecraft takes an angled view toward Saturn, showing the southern reaches of the planet with the rings on a dramatic diagonal.
North on Saturn is up and rotated 16 degrees to the left. This view looks toward the southern, unilluminated side of the rings from about 14 degrees below the ringplane. The rings cast wide shadows on the planet’s southern hemisphere.
The moon Enceladus (313 miles, or 504 kilometers across) appears as a small, bright speck in the lower left of the image.
The image was taken with the Cassini spacecraft wide-angle camera on June 15, 2012 using a spectral filter sensitive to wavelengths of near-infrared light centered at 752 nanometers. The view was obtained at a distance of approximately 1.8 million miles (2.9 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 72 degrees. Image scale is 11 miles (17 kilometers) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.
Credit: NASA/JPL-Caltech/Space Science Institute
Cosmic Love by Phillip Schumacher
Under the Stars by Phil Hart
The Hubble Space Telescope stitches together 10 years’ worth of photos into an extreme view.
In the Image: eXtreme Deep Field View Of Space NASA, ESA, G. Illingworth, D. Magee, and P. Oesch (University of California, Santa Cruz), R. Bouwens (Leiden University), and the HUDF09 Team
Take a deep breath, stargazers: this is the farthest we’ve seen into the heart of the universe. The eXtreme Deep Field, or XDF, as the photo’s called, shows about 5,500 galaxies, although some are as much are only one ten-billionth of the brightness needed to be seen by human eyes.
The photo is actually something of a mosaic: there are 10 years’ worth of photos from the Hubble Space Telescope. The Hubble Ultra Deep Field, an image showing a slice of space in the constellation Fornax, was assembled in 2003 and 2004 with data from Hubble; it was a major leap toward seeing the edges of the universe, but with help from an infrared camera attached to Hubble in 2008, along with use of visible light, we got what you see here, an image of what it’s like closer than ever to the first galaxies.
Ten things you probably did’nt know about dark energy
Dark energy is the biggest mystery in the cosmos, pervading the vast emptiness of space for billions of light-years. But if you thought you knew everything there was to know about this strange force, think again.
Discovery Space sat down with Michael Turner, a cosmologist at the University of Chicago, to pin down the 10 biggest things you didn’t know about dark energy.
10. Dark Energy’s Discoverer Didn’t Coin the Term
Who came up with the term? “I did,” Turner said. “That’s because when you find something new and weird, you have to name it. It can’t just be ‘the funny stuff that helps the universe speed up.’”
The term is also used to say that it’s different than dark matter, which is yet another weird constituent of the cosmos, and behaves more like energy than anything else that we know of.
9. Albert Einstein First Stumbled on Dark Energy’s Path
Thing is, Einstein didn’t even know it.
The German-born scientist derived an historic ”cosmological constant” to make the universe static — or in other words, prevent gravity from steering the cosmos into a “big crunch” billions of years in the future.
“Instead of counteracting gravity, however, Einstein’s cosmological constant overpowers it and causes the universe to expand at an accelerating pace,” Turner told Discovery Space. “People like to say that even when Einstein thought he made a mistake he was right, but that’s a bit of a stretch.”
If Einstein’s cosmological constant does exist, it’s about four times stronger than he first anticipated.
“We don’t think the universe is static,” he said. “It’s inconsistent with what we see out there.”
8. Dark Energy Could Be Nothing
The “gravity” of dark energy is repulsive, making it a large-scale anti-gravity that acts like an overzealous traffic cop between clusters of galaxies. What’s between those galaxies? Empty space.
“The simplest explanation for dark energy is that it’s associated with something called the ‘quantum vacuum,’” Turner said.
According to quantum mechanics — which explains how the universe works on a small scale — empty space is full of particles living on borrowed time and energy, Turner explained. So it’s not too unreasonable to suggest dark energy might also occupy that “empty” space.
7. Dark Energy Can’t Be Broken into Particles
About 2,500 years ago, Democritus suggested there were four elements in the universe: air, fire, earth and water, later adding “ether.”
“He started on this path that everything is made of indivisible particles called atoms, and that path eventually led us to subatomic particles called quarks today,” Turner said. “But dark energy isn’t made of quarks, or any other particle.”
6. Dark Energy Is Everywhere
According to Einstein’s famous equation E=MC^2, matter can be converted completely into energy, and the universe can be divided into a “pie” of energy.
“One of the most important things about dark energy is that it makes up most of the stuff in the universe,” Turner told Discovery Space. ” however, locally, we don’t notice it.”
The breakdown of the pie is roughly like this:
- 74 percent is dark energy
- 22 percent is dark matter
- 3.6 percent is nearly invisible gas between stars
- 0.4 percent is stars, planets, moons and everything else. Including you.
5. Dark Energy Is the Most Elastic Substance Ever
“It’d be safe to say it’s more than a zillion times more elastic than anything we know of,” Turner said. “Even NASA’s most stretchy material, whatever it may be.”
If one were to “weigh” the energy of dark energy in a large coffee cup, it would be about 1 x 10^-27 grams (0.000000000000000000000000001 grams) or, in other words, not a whole lot.
If you do the math, Turner explained, contracting a volume of dark energy between here and the sun would create enough juice to power the Earth for about nearly 100,000 years.
4. Dark Energy Shaped the Universe
The Big Bang is thought to have kick-started the universe we live in, but after the event, dark energy began to seize its grip on matter and overcome gravity.
“Our universe was shaped by battle between dark energy and matter,” Turner said. “For the first 8 billion years or so of the universe’s existence, the gravity of matter held sway and clusters of galaxies formed.”
Roughly five billion years after that — or about one billion years ago — dark energy took over, and “put its foot on accelerator,” Turner said. “The expansion of the universe began speeding up and no larger structures were built.”
3. Dark Energy May Not be Energy at All
If it’s not made of particles, and may be nothing, is it really safe to call it energy?
“Not in the least bit,” Turner told Discovery Space. “There may very well be no dark energy at all.”
Instead, Turner suggested that Einstein’s ideas about gravity might need to be replaced.
“Few people think Einstein got the last word on gravity. His story didn’t incorporate the details of the universe at the atomic level,” he said, which is what might hold the key to gravity.”
2. Dark Energy Holds the Destiny of the Cosmos
Until we understand what dark energy is, Turner thinks we won’t really know what the fate of the universe is.
“It could continue to accelerate as it is,” he said. “If it does, then in about 100 billion years the galaxies around us will be speeding away from us too quickly to see.”
Another scenario is that the acceleration of the universe’s expansion may be doubled. And that’s bad news for everyone that might be out there — the cosmos will rip itself to shreds.
“We don’t know if the acceleration we see today is accelerating,” Turner said. “If it is, the ‘big rip’ will occur in roughly 20 billion years.”
One last option is equally as frightening.
“Maybe dark energy’s next trick is to decelerate expansion and lead to the collapse of the universe,” Turner said. “We’ve trapped ourselves time and time again believing in the simplest case, only to correct ourselves. If you want to be squeaky-clean correct, we can’t confidently guess the future of the universe yet.”
1. No One Knows What Dark Energy Is
If you thought you were clueless, even the experts don’t know.
“Welcome to the club,” Turner said. “It’s the most profound mystery in all of science. It ties together the destiny of the universe, mysteries about gravity and quantum nothingness. How’s that for a mystery?”
Cassini named the four moons he discovered (Tethys, Dione, Rhea and Iapetus) Sidera Lodoicea (“the stars of Louis”) to honor king Louis XIV. Cassini found Dione using a large aerial telescope he set up on the grounds of the Paris Observatory, The satellites of Saturn were not named until 1847, when William Herschel’s son, John Herschel published Results of Astronomical Observations made at the Cape of Good Hope, and suggested the names of the Titans, sisters and brothers of Cronos (the Greek Saturn), be used.
Messier 78: A Reflection Nebula in Orion
This new image of the reflection nebula Messier 78 was captured using the Wide Field Imager camera on the MPG/ESO 2.2-metre telescope at the La Silla Observatory, Chile. This colour picture was created from many monochrome exposures taken through blue, yellow/green and red filters, supplemented by exposures through a filter that isolates light from glowing hydrogen gas. The total exposure times were 9, 9, 17.5 and 15.5 minutes per filter, respectively.
Newfound Alien Planet a Top Contender to Host Life
In the image: Artist’s rendition of the “super Earth” Gliese 163c, which may be capable of supporting microbial life.
A newly discovered alien planet may be one of the top contenders to support life beyond Earth, researchers say.
The newfound world, a “super Earth” called Gliese 163c, lies at the edge of its star’s habitable zone — that just-right range of distances where liquid water could exist.
Royal Observatory Picks Best Astronomy Photos of the Year
1. Seeing Stars Spin
This gorgeous image required an all-night exposure, made on a night with no moon and clear skies. It was shot on Blackcomb Mountain in British Columbia, Canada.
The photographer, Kim Eijdenberg, told National Geographic’s My Shot, “It’s amazing to think it’s really us who are spinning in relation to the stars.” That’s because the Earth rotates on its axis and revolves around the sun.
2. The Seven Sisters
The Pleiades (the Seven Sisters, or officially M45) is a tight cluster of stars that is visible to the naked eye on dark nights. Here, the group is shown through the wide-field view of the Mosaic camera on the WIYN 0.9-meter telescope on Kitt Peak, Arizona. Blue, green, and red filters were applied.
The cluster of hot, big stars is accented by blue nebulae that are formed as the starlight scatters off dust particles in the interstellar space between the luminous bodies. The stars of Pleiades are considered middle-aged, and they are located in the constellation Taurus. The cluster is among the nearest to Earth.
The Pleiades are known as Subaru in Japan, a name that was adopted by the car company. Many cultures had rich folklore about the star cluster, from the Norse people to the Berbers, Arabs, Hebrews, and of course the Greeks, who called them the Seven Sisters.
3. Dark Nebula
A dark nebula called LDN 810 is visible through the wide-field view of the Mosaic camera on the Mayall 4-meter telescope at Kitt Peak National Observatory. The dark part in the center of the image is made up of gas and dust and is a place where new stars are forming. A faint trail of dust and gas extends from the center of the image to the upper-left corner.
The astral feature was first described in 1962 by B.T. Lynds. This image was made with violet, blue, green, and red filters.
4. Lonely Galaxy
Without neighbors, the “lonely” galaxy DDO 190 is relatively small and lacks clear structure, according to NASA.
In this recently released Hubble Space Telescope picture, older, reddish stars dot the edges of the so-called dwarf irregular galaxy. Younger, bluish stars crowd its interior.
(Source: National Geographic)