The universe is a weird place. Here’s a look at some of the strangest things in the cosmos.
Like Superman’s alter-ego, Bizzaro, the particles making up normal matter also have opposite versions of themselves. An electron has a negative charge, for example, but its antimatter equivalent, the positron, is positive. Matter and antimatter annihilate each other when they collide and their mass is converted into pure energy by Einstein’s equation E=mc2. Some futuristic spacecraft designs incorporate anti-matter engines.
If a radical new “braneworld” theory of gravity is correct, then scattered throughout our solar system are thousands of tiny black holes, each about the size of an atomic nucleus. Unlike their larger brethren, these mini-black holes are primordial leftovers from the Big Bang and affect space-time differently because of their close association with a fifth dimension.
Cosmic Microwave Background
Also known as the CMB, this radiation is a primordial leftover from the Big Bang that birthed the universe. It was first detected during the 1960s as a radio noise that seemed to emanate from everywhere in space. The CMB is regarded as one of the best pieces of evidence for the theoretical Big Bang. Recent precise measurements by the WMAP project place the CMB temperature at -455 degrees Fahrenheit (-270 Celsius).
Scientists think it makes up the bulk of matter in the universe, but it can neither be seen nor detected directly using current technologies. Candidates range from light-weight neutrinos to invisible black holes. Some scientists question whether dark matter is even real, and suggest that the mysteries it was conjured to solve could be explained by a better understanding of gravity.
Until about the early 1990s, the only known planets in the universe were the familiar ones in our solar system. Astronomers have since identified more than 500 extrasolar planets (as of November 2010). They range from gargantuan gas worlds whose masses are just shy of being stars to small, rocky ones orbiting dim, red dwarfs. Searches for a second Earth, however, are still ongoing. Astronomers generally believe that better technology is likely to eventually reveal worlds similar to our own.
Gravity waves are distortions in the fabric of space-time predicted by Albert Einstein’s theory of general relativity. The gravitational waves travel at the speed of light, but they are so weak that scientists expect to detect only those created during colossal cosmic events, such as black hole mergers like the one shown above. LIGO and LISA are two detectors designed to spot the elusive waves.
Like life on Earth, galaxies can “eat” each other and evolve over time. The Milky Way’s neighbor, Andromeda, is currently dining on one of its satellites. More than a dozen star clusters are scattered throughout Andromeda, the cosmic remains of past meals. The image above is from a simulation of Andromeda and our galaxy colliding, an event that will take place in about 3 billion years.
Neutrinos are electrically neutral, virtually mass-less elementary particles that can pass through miles of lead unhindered. Some are passing through your body as you read this. These “phantom” particles are produced in the inner fires of burning, healthy stars as well as in the supernova explosions of dying stars. Detectors are being embedded underground, beneath the sea, or into a large chunk of ice as part of IceCube, a neutrino-detecting project.
These bright beacons shine to us from the edges of the visible universe and are reminders to scientists of our universe’s chaotic infancy. Quasars release more energy than hundreds of galaxies combined. The general consensus is that they aremonstrous black holes in the hearts of distant galaxies. This image is of quasar 3C 273, photographed in 1979.
Quantum physics tells us that contrary to appearances, empty space is a bubbling brew of “virtual” subatomic particles that are constantly being created and destroyed. The fleeting particles endow every cubic centimeter of space with a certain energy that, according to general relativity, produces an anti-gravitational force that pushes space apart. Nobody knows what’s really causing the accelerated expansion of the universe, however.
“We’re going to explore the cosmos in a ship of the imagination, unfettered by the ordinary limits on speed and size, drawn by the music of cosmic harmonies. It can take us anywhere in space and time. Perfect as a snowflake, organic as a dandelion seed, it will carry us to worlds of dreams, and worlds of facts. Come with me.”
These images show the evolution of the light echo around the star V838 in the constellation of Monoceros. They were taken by the Hubble Advanced Camera for Surveys in November 2005 (above) and again in September 2006 (below). The numerous whorls and eddies in the interstellar dust are particularly noticeable. Possibly they have been produced by the effects of magnetic fields in the space between the stars.
Voyager 1 captured this mosaic on Io on March 4, 1979, as a nearly full-phase Io appeared to travel across Jupiter’s terminator. Viewed near the edge of its disk and at local dusk, only the uppermost blue hazes of Jupiter’s atmosphere are visible.
The mosaic, which consists of four clear-filter images followed by violet, blue, orange, and green frames, is a great challenge to assemble because in the 11 minutes it took Voyager to record and transmit the 6 images (from 22:36:35 to 22:47:48) Io completely transited the terminator, and because the color frames are not complete, with pieces of Io cut off. Source images can be downloaded here.
Credit: NASA / JPL / Ted Stryk
Black holes come in a variety of sizes, ranging from 10 times the mass of the sun to a billion times as massive. But new research shows that black holes of completely different masses, ages and locations can produce jets of ionized gas that behave similarly.
Image: This illustration shows a black hole emitting jets of fast-moving plasma above and below it, as matter swirls around in an orbiting disk. Credit: NASA’s Goddard Space Flight Center
“As scientists, we are always seeking universal principles,” Rodrigo Nemmen, of NASA’s Goddard Space Flight Center in Greenbelt, Md., told SPACE.com.
Nemmen and his colleagues studied a wide variety of black holes in an attempt to compare how efficiently their jets emitted light. “I was very surprised,” Nemmen said of the results.
Discovering similarities between ancient supermassive black holes in the center of distant galaxies and baby black holes born as stars collapse should help scientists gain a firmer understanding of these jets.
Black holes are well known for their ability to pull matter into them. But not all material near a black hole finds itself lost. Some bits of matter just outside the point of no return (called the event horizon) are accelerated away at near-light speeds, creating jets of particles shooting out above and below the black holes.
“I like to call black holes ‘cosmic LHCs,’ or very powerful particle accelerators,” Nemmen said, referring to the Large Hadron Collider, an underground machine in Switzerland that speeds protons to 99.9999991 percent the speed of light.
When matter is spun away from a black hole in the form of a jet, most of its energy goes into its motion, but some of it is changed into light in the form of gamma-rays. Nemmen and his team studied findings on 293 previously observed black holes and calculated how efficiently the jets converted energy to light. They found that the rate scaled across the range of black holes.
“This was one of the surprises of this work, that this efficiency of conversion of the energy into light is essentially the same for black holes with very different masses, very different ages and completely different environments,” Nemmen said.
Black holes are powerful beasts, interesting in and of themselves. But by accelerating ionized gas, they also have the potential to change their environment. Heating up space, they could affect the production of new stars, thereby influencing the galaxy they live in.
“These jets might be powerful agents of creating changes in the host galaxy,” Nemmen said.
Scientists still don’t have a strong understanding of how these violent particle outflows form. But the fact that the energy efficiency of the jets scales across black holes may help theorists better understand how something that pulls in most particles could shoot away others, and how the outflow of energy may affect surrounding space.
The findings were published online today (Dec. 13) in the journal Science.
Located in a relatively vacant region of space about 4200 light-years away and difficult to see using an amateur telescope, the lonesome planetary nebula NGC 7354 is often overlooked.
However, thanks to this image captured by the NASA/ESA Hubble Space Telescope we are able to see this brilliant ball of smoky light in spectacular detail.
Just as shooting stars are not actually stars and lava lamps do not actually contain lava, planetary nebulae have nothing to do with planets. The name was coined by Sir William Herschel because when he first viewed a planetary nebula through a telescope, he could only identify a hazy smoky sphere, similar to gaseous planets such as Uranus.
The name has stuck even though modern telescopes make it obvious that these objects are not planets at all, but the glowing gassy outer layers thrown off by a hot dying star.
It is believed that winds from the central star play an important role in determining the shape and morphology of planetary nebulae. The structure of NGC 7354 is relatively easy to distinguish. It consists of a circular outer shell, an elliptical inner shell, a collection of bright knots roughly concentrated in the middle and two symmetrical jets shooting out from either side. Research suggests that these features could be due to a companion central star, however the presence of a second star in NGC 7354 is yet to be confirmed.
“A hybrid result involving the central area of the Veil Nebula Complex in Cygnus comprised of 150 minutes of Hydrogen-Alpha, 150 minutes of O-III and 30 minutes each for RGB.
Both the h-alpha and O-III filters do an admirable job in picking up significant signal which otherwise is missed or overlooked, thus yielding a very impressive hybrid result.” — Anthony Ayiomamitis
Distance: 8,000 light years
Massive stars lie within NGC 6357, the central part of which is shown in the very middle of this image. That central region spans about 10 light years and the whole expansive complex lies about 8,000 light years away in the tail of the constellation Scorpius.
In fact, positioned just below center in this view of NGC 6357, star cluster Pismis 24 includes some of the most massive stars known in the galaxy, stars with over 100 times the mass of the Sun. The nebula’s bright central region also contains dusty pillars of molecular gas, likely hiding massive protostars from the prying eyes of optical instruments. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity. The overall glow of the nebula results from the emission of light from ionized hydrogen gas.
The unusual name of “War and Peace” was given to this nebula not because of the famous novel by Tolstoy, but was given to this object by scientists working on the Midcourse Space Experiment. They noted that the bright, western part of the nebula resembled a dove, while the eastern part looked like a skull in their infrared images. Unfortunately this effect cannot be seen in the visible-light image presented here. The object is also occasionally nicknamed the Lobster Nebula.
NGC 6357 was first recorded visually by John Herschel from South Africa in 1837. He only recorded the brightest central parts and the full scale of this huge nebula was only seen in photographs much later.