Planetary Collective presents a short film documenting astronauts’ life-changing stories of seeing the Earth from the outside – a perspective-altering experience often described as the Overview Effect.
Tag Archive: Space
Researchers exploit the strange properties of a liquid metamaterial to watch Minkowski spacetimes leap in out and of existence.
Metamaterials are synthetic substances with nanoscale structures that manipulate light. This ability to steer photons makes them the enabling technology behind invisibility cloaks and has generated intense interest from researchers.
The ability to guide light has more profound consequences, however. Various theoreticians have pointed out that there is a formal mathematical analogy between the way certain metamaterials bend light and the way spacetime does the same thing in general relativity. In fact, it ought to be possible to make metamaterials that mimic the behaviour of not only our own spacetime but also many others that cosmologist merely dream about.
Indeed, a couple of years ago we looked at a suggestion by Igor Smolyaninov at the University of Maryland in College Park that it ought to be possible to use metamaterials to create a multiverse in which different regions of the material corresponded to universes with different properties.
Today, Smolyaninov and a couple of buddies announce the extraordinary news that they have done exactly this. They’ve created a metamaterial containing many “universes” that are mathematically analogous to our own, albeit in the three dimensions rather than four.
When, a few weeks ago, astronomers announced that an Earth-sized planet had been detected orbiting a Alpha Centauri B, a star in the closest system of stars to our own, and that this planet might, just might, mean that there is another planet, maybe another Earth-sized one, maybe, just maybe, in that magical distance from a sun that could give rise to life, and that all this was taking place right there in our galactic backyard, the next thought was inevitable: What if there is life there?
What if we, the people of the early 21st century, could be among the generation — the first and only of all the generations ever — that would be first to know that we were not alone?
But then there is the inevitable letdown: Even if we did find a planet in one of those nearby stars’ habitable zone and even, even, if we could detect an atmosphere that could harbor life, then what? Alpha Centauri may be the closest star system to Earth, but it’s still four light years away. Voyager 1, our farthest-traveled probe is moving at *38,000 miles per hour*, and after 35 years, it’s still in our solar system (barely). Moving at Voyager’s speed, it would take 700 *centuries* for a missionto reach Alpha Centauri. With speeds like that, we stand to become the first generation to know life is out there, and to not be able to know much more than that. The prospect is maddening.
Of course, our only hope would be to travel at much, much greater speeds. As MIT astronomer Sara Seager explained here at The Atlantic to Ross Andersen:
There are a lot of people who think we have the capabilities to get to a tenth of the speed of light. People are using that number as a benchmark of what they think is attainable, whether it’s with a solar sail or nuclear pulse propulsion. If we could achieve that speed, then we could get to Alpha Centauri in just over 40 years.
Whenever I give a talk to a public audience I explain the hazards of living on a spacecraft for 40 years, the fact that life could be extremely tedious, and could possibly even include some kind of induced hibernation. But then I always ask if anyone in the audience would volunteer for a 40+ year journey, and every single time I get a show of hands. And then I say “oh I forgot to mention, it’s a one way trip,” and even then I get the same show of hands. This tells me that our drive to explore is so great that if and when engineers succeed at traveling at least 10 percent of the speed of light, there will be people willing to make the journey. It’s just a matter of time.
When researchers sent plants to the International Space Station in 2010, the flora wasn’t meant to be decorative. Instead, the seeds of these small, white flowers—called Arabidopsis thaliana—were the subject of an experiment to study how plant roots developed in a weightless environment.
Gravity is an important influence on root growth, but the scientists found that their space plants didn’t need it to flourish. The research team from the University of Florida in Gainesville thinks this ability is related to a plant’s inherent ability to orient itself as it grows. Seeds germinated on the International Space Station sprouted roots that behaved like they would on Earth—growing away from the seed to seek nutrients and water in exactly the same pattern observed with gravity.
Since the flowers were orbiting some 220 miles (350 kilometers) above the Earth at the time, the NASA-funded experiment suggests that plants still retain an earthy instinct when they don’t have gravity as a guide.
“The role of gravity in plant growth and development in terrestrial environments is well understood,” said plant geneticist and study co-author Anna-Lisa Paul, with the University of Florida in Gainesville. “What is less well understood is how plants respond when you remove gravity.”
The new study revealed that “features of plant growth we thought were a result of gravity acting on plant cells and organs do not actually require gravity,” she added.
Are there dark doings near the center of the Milky Way? That may be so when it comes to the collision of dark matter particles. Although such particles are invisible, we could still theoretically see the mess they make when they collide. It’s this idea that leads physicists to scour the galaxy for some glimmer of dark matter collisions. Spot a line produced by a pair of gamma-rays emanating from just the right spot and you may have found coveted clues to the dark matter mystery.
Now a collaboration of scientists using the Fermi Gamma-Ray Spacecraft’s Large Area Telescope instrument (Fermi–LAT) has confirmed seeing an unusual gamma-ray line near the galactic center. If the finding stands up to further scrutiny, it’s possible this line comes from the annihilation of dark matter.
In April theoretical physicist Christoph Weniger, now at the GRAPPA Institute in Amsterdam, analyzed Fermi–LAT’s publicly available data and spotted a strange gamma-ray line near the galactic center. There’s no known astrophysical event that can tidily explain this line—but the collision of dark matter particles might. If that were the case, it would be a major discovery: Once physicists spot the products of such an annihilation, they could begin to understand the particles that collided.
But there was a catch: Weniger is not a member of the Fermi-LAT collaboration and therefore cannot be able to account for the quirks of their instrument. What was needed was a weigh-in from Fermi-LAT collaboration physicists; they know the data best and would be able to confirm any hint of dark matter.
Scientists at the UA and in California have completed the most challenging large astronomical mirror ever made. The mirror will be part of the 25-meter Giant Magellan Telescope, which will explore planets around other stars and the formation of stars, galaxies and black holes in the early universe.
Scientists at the University of Arizona and in California have completed the most challenging large astronomical mirror ever made.
For the past several years, a group of optical scientists and engineers working at the UA Steward Observatory Mirror Laboratory underneath the UA’s football stadium have been polishing an 8.4-meter (27 ½ feet) diameter mirror with an unusual, highly asymmetric shape.
By the standards used by optical scientists, the “degree of difficulty” for this mirror is 10 times that of any previous large telescope mirror. The mirror surface matches the desired prescription to a precision of 19 nanometers – so smooth that if it were the size of the continental U.S., the highest mountains would be little more than a half-inch high.
This mirror, and six more like it, will form the heart of the 25-meter Giant Magellan Telescope, providing more than 380 square meters, or 4,000 square feet, of light-collecting area. The Giant Magellan Telescope will lead a next generation of giant telescopes that will explore planets around other stars and the formation of stars, galaxies and black holes in the early universe.
British scientists are to mimic black holes in the laboratory as part of a £2.35 million project looking at how matter and energy interact.
The team from Heriot-Watt University in Edinburgh will produce laser pulses whose energy is measured in trillions of watts.
They will be used to simulate conditions found around a black hole, a place where gravity is so strong that light cannot escape and the normal laws of physics break down.
Lead scientist Daniele Faccio said: “What we are creating is the same space-time structure which characterises a black hole. But we’re doing this with a light pulse, so we don’t actually have the mass which is associated with black holes.
“Gravitational black holes are generated by a collapsing star. We don’t actually have this collapsing star, so there’s no danger of being sucked into the black holes we’re generating here.”
The university has been awarded a three million euro (£2.35 million) grant by the European Research Council to investigate new areas of quantum physics.
Another study will look at how single photons and electrons interact with each other in computer chips.
Astronomers have used NASA’s Chandra X-ray Observatory to find evidence our Milky Way Galaxy is embedded in an enormous halo of hot gas that extends for hundreds of thousands of light years. The estimated mass of the halo is comparable to the mass of all the stars in the galaxy.
If the size and mass of this gas halo is confirmed, it also could be an explanation for what is known as the “missing baryon” problem for the galaxy.
Baryons are particles, such as protons and neutrons, that make up more than 99.9 percent of the mass of atoms found in the cosmos. Measurements of extremely distant gas halos and galaxies indicate the baryonic matter present when the universe was only a few billion years old represented about one-sixth the mass and density of the existing unobservable, or dark, matter. In the current epoch, about 10 billion years later, a census of the baryons present in stars and gas in our galaxy and nearby galaxies shows at least half the baryons are unaccounted for.
The Hubble Space Telescope (HST) has produced one of its most extraordinary views of the Universe to date.
Called the eXtreme Deep Field, the picture captures a mass of galaxies stretching back almost to the time when the first stars began to shine.
But this was no simple point and snap – some of the objects in this image are too distant and too faint for that.
Rather, this view required Hubble to stare at a tiny patch of sky for more than 500 hours to detect all the light.
“It’s a really spectacular image,” said Dr Michele Trenti, a science team member from the University of Cambridge, UK.
“We stared at this patch of sky for about 22 days, and have obtained a very deep view of the distant Universe, and therefore we see how galaxies were looking in its infancy.”
The XDF will become a tool for astronomy. The objects embedded in it can be followed up by other telescopes. It should keep scientists busy for years, enabling them to study the full history of galaxy formation and evolution.
The new vista is actually an updating of a previous HST product – the Hubble Ultra Deep Field.
This is the Earth’s song, pinging out contended chirrups into deep space.
The haunting sounds have been captured by Nasa’s twin Radiation Belt Storm Probe (RBSP) satellite, which launched on August 30 this year.
The satellites captured the chirping and whistling radio waves emitted by Earth’s magnetosphere on September 5.
The sound is known as ‘Earth’s chorus’ and can be heard by human ears – that is, assuming you could take your helmet off while floating in space.
Craig Kletzing, from the University of Iowa, is the principal investigator of the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) instruments on-board the satellites.
He said: ‘People have known about chorus for decades.
‘Radio receivers are used to pick it up, and it sounds a lot like birds chirping.
‘It was often more easily picked up in the mornings, which along with the chirping sound is why it’s sometimes referred to as “dawn chorus”.’
The radio waves are at frequencies which can be heard from the human ear, but sadly you might need to be in space and without a helmet – which is not medically advisable.
You might also encounter the tricky problem of sound not travelling through the vacuum.
This galaxy is so large, so fully-formed, astronomers say it shouldn’t exist at all. It’s called a “grand-design” spiral galaxy, and unlike most galaxies of its kind, this one is old. Like, really, really old. According to a new study conducted by researchers using NASA’s Hubble Telescope, it dates back roughly 10.7-billion years — and that makes it the most ancient spiral galaxy we’ve ever discovered.
“The vast majority of old galaxies look like train wrecks,” said UCLA astrophysicist Alice Shapley in a press release. “Our first thought was, why is this one so different, and so beautiful?”
Shapley is co-author of the paper describing the discovery, which is published in the latest issue of Nature. She and her colleagues had been using Hubble to investigate some of our Universe’s most distant cosmic entities, but the discovery of BX442 — which is what they’ve dubbed the newfound galaxy — came as a huge surprise.
“The fact that this galaxy exists is astounding,” said University of Toronto’s David Law, lead author of the study. “Current wisdom holds that such ‘grand-design’ spiral galaxies simply didn’t exist at such an early time in the history of the universe.”
Thirty-five years ago today, the Voyager 1 launched into space in a quest to explore the outer Solar System.
Enjoy this animation by Adam Winnik.
Astronomers have made a sweet discovery: simple sugar molecules floating in the gas around a star some 400 light-years away, suggesting the possibility of life on other planets.
The discovery doesn’t prove that life has developed elsewhere in the universe—but it implies that there is no reason it could not. It shows that the carbon-rich molecules that are the building blocks of life can be present even before planets have begun forming.
Scientists use the term “sugar” to loosely refer to organic molecules known as carbohydrates, which are made up of carbon, hydrogen, and oxygen.
The molecules that the team detected in space are the simplest form of sugar, called glycoaldehyde, explained lead astronomer Jes Jørgensen of Denmark’s Copenhagen University.
What Earth looked like from between 13 billion years ago to how it will likely look 250 million years in the future.
Harvard scientists use 1,024-core supercomputer to produce a partial simulation of the life of the universe, modelling thousands of individual stars and galaxies with a Arepo, new software for cosmological simulations of galaxy formation across billions of years.
The start of the Universe should be modeled not as a Big Bang but more like water freezing into ice, according to a team of theoretical physicists at the University of Melbourne and RMIT University.
They suggest that by investigating the cracks and crevices common to all crystals — including ice — our understanding of the nature of the Universe could be revolutionized.
Albert Einstein assumed that space and time were continuous and flowed smoothly, but we now believe that this assumption may not be valid at very small scales, said Project lead researcher James Q. Quach.
“A new theory, known as Quantum Graphity, suggests that space may be made up of indivisible building blocks, like tiny atoms,” he said. “These indivisible blocks can be thought about as similar to pixels that make up an image on a screen. The challenge has been that these building blocks of space are very small, and so impossible to see directly.”
However Quach and his colleagues believe they may have figured out a way to see them indirectly.
“Think of the early universe as being like a liquid,” he said. “Then as the universe cools, it ‘crystallizes’ into the three spatial and one time dimension that we see today. Theorized this way, as the Universe cools, we would expect that cracks should form, similar to the way cracks are formed when water freezes into ice.”
Because black holes are impossible to see, one of scientists’ best hopes to study them is to look for the ripples in space-time, called gravitational waves, that they are thought to create.
Gravitational waves would be distortions propagating through space and time caused by violent events such as the collision of two black holes. They were first predicted by Einstein’s general theory of relativity; however, scientists have yet to find one.
That could change when the latest version of a gravitational wave-hunting facility gets up and running. The Laser Interferometer Gravitational Wave Observatory (LIGO) is actually a pair of observatories, in Louisiana and Washington state, that began operating in 2002. Newly sensitized detectors are being added to both.
“The advanced LIGO detectors that are now being installed will see out through a substantial part of the universe,” said California Institute of Technology emeritus professor of physics Kip Thorne, a leading proponent of LIGO. “We expect to see black holes colliding at a rate of perhaps somewhere between once an hour and once a year.”
The largest ever three dimensional map of galaxies and black holes was released by astronomers today. It will help explain the mysterious dark matter and dark energy that they know makes up 96 percent of the universe.
The map is the creation of the Sloan Digital Sky Survey III (SDSS-III) an international project mapping the Milky Way in which a team from the University of Portsmouth is the only UK institution. Early last year, the SDSS-III released the largest-ever image of the sky and astronomers have used new data to expand this image into a full three-dimensional map.
Data Release 9 (DR9) includes images of 200 million galaxies and spectra of 1.35 million galaxies, including 540,000 spectra of new galaxies from when the universe was half its present age. Spectra show how much light a galaxy gives off at different wavelengths. Because this light is shifted to longer redder wavelengths as the Universe expands, spectra allow scientists to work out how much the Universe has expanded since the light left each galaxy.
It will allow better estimates of how much of the universe is made up of dark matter – matter that can’t be seen directly see because it doesn’t emit or absorb light – and dark energy, the even more mysterious force that drives the accelerating expansion of the universe.
Dear NASA, any chance you can send another Curiosity rover to the U.S. Congress to check if there’s intelligent life in there? Thanks a lot!
If you’ve always wanted to live on a distant world, Dutch company Mars One wants to give you your chance to settle on the red planet. There’s only one catch: You’ll never be able to return to Earth.
Next year, Mars One will hold a worldwide lottery to select 40 people to train to be civilian astronauts. That group will be sent to live in a desert simulation for three months, after which the initial pool will be whittled down to 10. By 2023, this group will be sent to Mars to form the first permanent human settlement.
According to Bas Lansdorp, founder of Mars One, “We will send humans to Mars in 2023. They will live there the rest of their lives. There will be a habitat waiting for them, and we’ll start sending four people every two years.”
Once the new settlement has begun to thrive, the possibility for a return visit to Earth may open up. Still, that’s not guaranteed. Says Lansdorp, “our astronauts will be offered a one-way trip. We have no idea when it will be possible to offer return tickets.”
Joining up with Mars One is probably the most cost-effective way you’ll ever set foot on Mars. After all, buying a round-trip ticket to Mars from space tourism company Space X will cost you $500,000
Source: Yahoo
On board the International Space Station, ESA astronaut André Kuipers just put up picture of himself playing with water in space:
