Cluster of galaxies Galaxies in this image, left to right: Upper inner left, NGC 3193; middle, NGC 3190; upper right (2 o’clock), NGC 3187; lower right (4 o’clock), NGC 3185.

Examining a wide range of astronomical source data, the team assembled what they’re calling a new picture of our cosmic neighborhood. Companion galaxies, star clusters and loose gases are all properly aligned with the galactic disk, according to the team, led by Marcel Pawlowski at the University of Bonn.

This newly-discovered organizational structure is huge — it starts around 33,000 light years from the center of the Milky Way, and reaches 1 million light years. As the companion galaxies and clusters move about the Milky Way, they shed material like stars and gas, which forms long tails around their cosmic trajectories. These trailers also follow the galactic plane, the researchers say. Something is responsible for this organization, but the German team says it isn’t dark matter. They have a few ideas, including that the Milky Way collided with another galaxy 11 billion years ago, and the current companions are just debris following the galactic gravitational field.

“We were baffled by how well the distributions of the different types of objects agreed with each other,” said Pavel Kroupa, professor of astronomy at the University of Bonn, in a news release.

Dark matter is said to make up 23 percent of the mass-energy of the universe, much more than regular, baryonic matter that we can see. Its existence is inferred partly by its effects on galaxy distribution and galaxy cluster evolution. But the Milky Way’s satellite galaxies don’t trace a dark matter pattern, Pawlowski said in a blog post. He also notes that nobody has been able to find a dark matter particle yet, despite a slew of efforts around the world in all sorts of interesting configurations. Maybe they’re not finding it because it isn’t there?

Here’s the problem, though: Galaxy rotations (among other phenomena) cannot be explained by existing physics without something like dark matter. It fits the equations so well, it’s become pretty much accepted theory. But if we can’t find it — and if the structures that are supposed to help prove its existence can’t do that, either — then we’ll have to come up with something else.

“Our very understanding of space-time and matter are now at stake,” Pawlowski said.

Edwin Hubble first observed this phenomenon in 1929, when he noticed that the light from distant galaxies shifted to the red end of the spectrum, as though it had been stretched as it traveled through space. By measuring the wavelengths of the light, Hubble observed that galaxies were expanding away from each other at a rate proportional to their distance from one another.

In the beginning, the universe was a single point. Where was that? It was, and still is, everywhere. Scientists even have proof: Light from the big bang, in the form of cosmic radiation, fills the sky in every direction.

Enceladus and its Plumes of Water

A new assessment by the Space Science Board looks at which destinations are most in need of protection from microbes — Europa, Enceladus, Titan, and Triton, it concludes — and sets out a series of protocols for deciding how and where best to assess and deal with the risk.

COSPAR [Committee on Space Research] guidelines require that less than 1 in 10,000 missions will deliver a single viable microbe that is able to grow on a solar system destination, i.e., a 10^-4 probability of contamination per mission flown. Failure to meet this mandated objective could impose requirements for more stringent cleaning or terminal bioload-reduction procedures comparable to that employed by the Viking missions. In extreme cases, satisfying planetary protection requirements might require spacecraft redesign or cancellation of an entire mission.

The explosion unleashed a rather large coronal mass ejection (CME), those sometimes-menaces that threaten satellites, astronauts and terrestrial electronics, though the CME was not pointed toward earth. So instead of a space weather warning, we get this: beautiful imagery and footage of this M1 class (that’s like a medium) solar flare and prominence captured by NASA’s Solar Dynamics Observatory. While it was quite pleasant here on the Earth yesterday, click play below to see just how crazy things were getting on the surface of the sun.

A Warp Field, According to the Alcubierre Drive

The Alcubierre warp drive–proposed by a Mexican physicist of the same name back in the 1990s–is a theoretical mechanism by which a spacecraft could deform the space-time continuum in a bubble around itself so it could travel faster than the speed of light while still staying within the parameters of special relativity. So a couple of honors students and their professor at the U. of Sydney School of Physics decided to take the Alcubierre warp drive for a theoretical spin. Their findings: there’s no soft landing at the other end of warp speed.

It turns out that bending the space-time continuum has its hazards. During faster-than-light travel, particles that come in contact with this Alcubierre bubble get trapped and accumulate in front it. Some particles can even enter the warp bubble. There is an aggregating effect here, the physicists found, so the longer the bubble travels, the more particles accumulate in front of it.

When the spacecraft is finally decelerated at its destination, that energy is released all at once with such high energy that virtually anything they come in contact with would be instantly destroyed. The particles that wormed their way inside the bubble could also threaten the spacecraft itself. This could be handy if your cruiser drops out of warp speed in the midst of an asteroid field, but it also means that if you dropped out of warp too close to your destination planet you could inadvertently wipe it off the interstellar map. Don’t tell The Galactic Empire.

Nomad planets have only been confirmed in the last year or so, mostly by monitoring nearby stars to see if and when their light is "refocused" by a large passing object, like a planet. This new study is more math-based; it relies on the known gravitational pull of the entire galaxy, and how that might divide up into objects ranging in size from Pluto-sized rocks to Jupiter-sized giants. The research suggests that there may be as many as 100,000 more nomad planets than there are stars in the galaxy.

The research has some pretty interesting implications; our understanding of interstellar object behavior doesn’t really include unattached planets, and the search for extraterrestrial life could be the first field to really see a change from the survey. Nomad planets don’t have the light and warmth from a star to nurture life, but they actually might not even need it: with a thick atmosphere and a significantly radioactive core, they might theoretically be able to retain enough heat to serve as solo carriers of life through the galaxy.

Gravitational Lensing: This image of galaxy cluster MACS J1206.2-0847 shows the gravitational lensing effect of dark matter on distant galaxies. In a new exoplanet population paper, astronomers used microlensing to sense the presence of planets around other stars. The lensing was not as extreme as this, but works somewhat like a magnifying glass, brightening the light of a star lined up behind the planetary system.

“Planets are like bunnies; you don’t just get one, you get a bunch,” said Seth Shostak, a senior astronomer at the SETI Institute who was not involved in this research. “So really, the number of planets in the Milky Way is probably like five or 10 times the number of stars. That’s something like a trillion planets.”

Of course there’s no way to know, at least not yet, how many of these worlds could be hospitable to forms of life as we know it. But the odds alone are tantalizing, Shostak said.

“It’s not unreasonable at this point to say there are literally billions of habitable worlds in our galaxy, probably as a lower limit,” he said. “Maybe they’re all sterile as an autoclave, but it doesn’t seem very likely, does it? That would make us very odd.”

“The numbers are huge by any human standard, but we are still looking at only a tiny bit of our galaxy,” said John Gribbin, an astronomer and science writer who just published a book called “Alone in the Universe.” “[This research] does further our understanding of how things like planets form and how stars form, but there is a long way to go before we can say there is life on any of these planets, and further to go before we get to civilization.”

The new planetary plenitude is derived from a six-year survey of millions of stars studied with an international network of southern hemisphere telescopes. Astronomers used a delicate detection method called gravitational microlensing, which is one of three trusty ways to find extrasolar planets. Kepler uses the transit method, detecting blips in star brightness as planets cross in front of them. Other observatories use the radial velocity method, measuring the wobble caused by the gravitational tug of a planet on its star. Both of these are helpful for finding planets that are either huge or hug tightly to their stars. But the gravitational microlensing method can be used to find planets over a wider mass range and a wider orbital distance.

La Silla Observatory: The Milky Way seen above the dome of the Danish 1.54-metre telescope at ESO’s La Silla Observatory in Chile, used to search for exoplanets using the microlensing technique. The central part of the Milky Way is visible behind the dome of the ESO 3.6-metre telescope; on the right, the Magellanic Clouds.

It works by using the host star and its putative planets as a lens. The gravitational field of the host solar system magnifies the light of a star in the background. If the host star does have a planet, the planet essentially widens the lens, and this is an effect that can be measured. Such an alignment is incredibly rare, so an international team of researchers examined 100 million stars every night and noted ones with promising light curve amplifications, examining them in higher resolution. From 2002 to 2007, the team observed 500 such stars. In 10 cases, they could directly see the lensing effect of a planet. A statistical analysis showed one in six of the stars studied hosts a planet of similar mass to Jupiter, half have Neptune-mass planets and two thirds have super-Earths. Combining the results suggests that the average number of planets around a star is greater than one, the astronomers say in a new Nature paper.

“Together, the three methods are, for the first time, able to say something about how common our own solar system is, as well as how many stars appear to have Earth-size planets in the orbital area where liquid what could in principle exist as lakes, rivers and oceans — that is to say, where life as we know it from Earth could exist,” said Uffe Gråe Jørgensen, head of the Astrophysics and Planetary Science group at the Niels Bohr Institute at the University of Copenhagen and an author of the paper.

With so many planets, it could be easy to assume the odds have just gotten much better for alien life hunters, but it’s not necessarily the case because scientists still don’t know what’s necessary for life to form, said Paul Davies, a cosmologist and astrobiologist at Arizona State University.

“How much real estate is out there doesn’t matter,” he said. “My guess is there would be some hundreds of millions of Earth-like planets in the Milky Way, but that is no good to you if the probability of life forming on one of them is one in a trillion.”

The lack of knowledge hasn’t stopped scientists from making educated guesses, however — take the Drake equation, devised by astronomer Frank Drake in 1961, which seeks to estimate the number of intelligent civilizations based on an equation of assumptions.

“All of the work that has been done since 1961 when this equation was concocted has gone in the same direction, namely, that our situation here is not so weird, not so strange, not so bizarre, not so special,” Shostak said. “We’re not unique, at least astronomically.”

We’re just one in millions.

A Plethora of Planets: This artist’s impression shows how common planets are around the stars in the Milky Way. The planets, their orbits and their host stars are all vastly magnified compared to their real separations. A six-year search that surveyed millions of stars using a technique called microlensing concluded that every star has at least one planet orbiting around it.

Behemoth Black Hole: This figure shows the immense size of the black hole discovered in the galaxy NGC 3842. The black hole is at its center and is surrounded by stars (shown as an artist’s concept in the central figure). The black hole is seven times larger than Pluto’s orbit. Our solar system (inset) would be dwarfed by it.

One of the monstrous black holes, in the center of the galaxy NGC 3842, weighs as much as 9.7 billion suns. It is about 331 million light-years away in the constellation Leo. The other one, NGC 4889, is of comparable or even greater mass, the researchers say — they’re not positive, but the numbers suggest it could be up to 21 billion solar masses. It’s 336 million light-years away in the Coma galaxy cluster.

The former heavyweight champ is a dwarf by comparison, tipping the scales at 6.3 billion solar masses. That black hole is at the center of the giant elliptical galaxy Messier 87.

Supermassive black holes of 10-billion-sun magnitude have been predicted based on the brightness of quasars, ultra-luminous distant objects that are largely thought to be spiraling discs surrounding the event horizons of black holes in the very early universe. But this is the first time such enormous black holes have ever been seen. They could be a missing link to the quasars, according to astronomer Michele Capellari, writing in a companion piece to the new black hole paper.

"These objects probably represent the missing dormant relics of the giant black holes that powered the brightest quasars in the early universe," she wrote.

To weigh the black holes, Nicholas McConnell and Chung-Pei Ma at the University of California-Berkeley used the Keck and Gemini observatories to measure the speed of stars moving around the black holes. The faster the stars were moving, the more gravity was needed to keep them in check, so the researchers used these velocities to calculate the black holes’ masses.

They found the black holes were much bigger than predictive math would suggest, which means astronomers still have a lot to learn about how the biggest black holes form and evolve.

“Our measurements suggest that different evolutionary processes influence the growth of the largest galaxies and their black holes,” the researchers write.

Our Own Black Hole, Through Adaptive Optics: Image of the center of our galaxy from laser-guide-star adaptive optics on the Keck Telescope. If a 10 billion solar mass black hole resided at the Milky Way’s center, its immense event horizon would be visible, as illustrated by the central black disk. The actual black hole at the galactic center is 2,500 times smaller, however.

Known as Gloria (GLObal Robotic telescopes Intelligent Array for e-Science), the three-year European project will ultimately include 17 telescopes on four continents, run by 13 partner groups from Russia, Chile, Ireland, the United Kingdom, Italy, the Czech Republic, Poland and Spain. Not only will users be able to control the telescopes from their computers, but they will also have access to the astronomical databases of Gloria and other organizations.

The telescope at Spain’s Montegancedo Observatory is serving as the model for Gloria. Located at the Universidad Politécnica de Madrid’s Facultad de Informática, it can already be remotely operated through the internet, using the university’s Ciclope Astro software. This same software will be used by all the Gloria telescopes, to ensure uniformity across the system.

The amount of time that individual users get on the telescopes will be based on their "Karma," determined by how popular their work is with their fellow users. It will reportedly be somewhat like YouTube, where users vote on each other’s video posts.

While the EUR2.5 million (US$3.4 million) project is intended to help armchair astronomers of all types explore the Universe for themselves, it will also be used for crowd-sourced research. The University of Oxford in particular will be using Gloria for its Galaxy Zoo project, in which users are recruited to help classify approximately a million galaxies. Astronomical events will also be broadcast on the system, to help promote Gloria and built its user community.

Yes, the universe itself will eventually outpace the speed of light. Just how this will happen is a bit complicated, so let’s begin at the very beginning: the big bang.

Around 14 billion years ago, all matter in the universe was thrown in every direction. That first explosion is still pushing galaxies outward. Scientists know this because of the Doppler effect, among other reasons. The wavelengths of light from other galaxies shift as they move away from us, just as the pitch of an ambulance siren changes as it moves past.

Take Hydra, a cluster of galaxies about three billion light years away. Astronomers have measured the distance from the Earth to Hydra by looking at the light coming from the cluster. Through a prism, Hydra’s hydrogen looks like four strips of red, blue-green, blue-violet and violet. But during the time it takes Hydra’s light to reach us, the bands of color have shifted down toward the red end—the low-energy end—of the spectrum. On their journey across the universe, the wavelengths of light have stretched. The farther the light travels, the more stretched it gets. The farther the bands shift toward the red end, the farther the light has traveled. The size of the shift is called the redshift, and it helps scientists figure out the movement of stars in space. Hydra isn’t the only distant cluster of galaxies that displays a redshift, though. Everything is shifting, because the universe is expanding. It’s just easier to see Hydra’s redshift because the farther a galaxy is from our own, the faster it is moving away.

There is no limit to how fast the universe can expand, says physicist Charles Bennett of Johns Hopkins University. Einstein’s theory that nothing can travel faster than the speed of light in a vacuum still holds true, because space itself is stretching, and space is nothing. Galaxies aren’t moving through space and away from each other but with space—like raisins in a rising loaf of bread. Some galaxies are already so far away from us, and moving away so quickly, that their light will never reach Earth. “It’s like running a 5K race, but the track expands while you’re running,” Bennett says. “If it expands faster than you can run, you’ll never get where you’re going."