The U.S. space agency shared a 2014 photo that showed what appears to be a jack-o’-lantern face on the sun. The image was seen in ultraviolet light by NASA’s Solar Dynamics Observatory satellite.
NASA explained the image this way:
“The active regions in this image appear brighter because those are areas that emit more light and energy. They are markers of an intense and complex set of magnetic fields hovering in the sun’s atmosphere, the corona. This image blends together two sets of extreme ultraviolet wavelengths…typically colorized in gold and yellow, to create a particularly Halloween-like appearance.”
Scientists from NASA's New Horizons mission released the first detailed images of the most distant object ever explored -- the Kuiper Belt object nicknamed Ultima Thule. Its remarkable appearance, unlike anything we've seen before, illuminates the processes that built the planets four and a half billion years ago. . . .
The new images -- taken from as close as 17,000 miles (27,000 kilometers) on approach -- revealed Ultima Thule as a "contact binary," consisting of two connected spheres. End to end, the world measures 19 miles (31 kilometers) in length. The team has dubbed the larger sphere "Ultima" (12 miles/19 kilometers across) and the smaller sphere "Thule" (9 miles/14 kilometers across).
The team says that the two spheres likely joined as early as 99 percent of the way back to the formation of the solar system, colliding no faster than two cars in a fender-bender.
This composite image of Ultima Thule was taken on Dec. 1. Photo: NASA/JHUAPL/SwRI
On New Year's Day, NASA's New Horizons spacecraft is expected to make history by conducting the most distant flyby ever, by zooming past an object a billion miles past Pluto. It's called "Ultima Thule," meaning "beyond the known world.
Why it matters: The spacecraft, which is the same one that sent back dazzling images of Pluto in 2015, is slated to be the first to explore an object in the Kuiper Belt -- a region of icy bodies beyond the orbit of Neptune that are thought to be leftovers from the solar system's early days.
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The goal of the mission is to learn more about the building blocks of planets. "In effect, Ultima should be a valuable window into the early stages of planet formation and what the solar system was like over 4.5 billion years ago," principal investigator Alan Stern wrote in a NASA blog post.
This is reallly exciting for us science geeks. This goes back to the first entry in "Earth: A Biography", which, as you'll no doubt recall, dealt with the origins of the universe and, finally, this planet we're sitting on.
There's a lot more at the link, and it's pretty interesting.
Eleven billion miles from Earth, NASA's long-lived Voyager 2 probe, still beaming back data 41 years after its launch in 1977, has finally moved into interstellar space, scientists revealed Monday, joining its sister ship Voyager 1 in the vast, uncharted realm between the stars.
Voyager 2 moved past the boundary of the heliosphere, the protective bubble defined by the sun's magnetic field and electrically charged solar wind, on Nov. 5. The transition was marked by a sharp decline in the number of charged particles detected by the spacecraft's plasma science experiment, or PLS.
The instrument has not detected any signs of the solar wind since then.
The news came a few days ago, but on cosmic time scales that’s still hot of the presses: LIGO, the twin instrument gravitational wave detectors, in collaboration with the European VIRGO detector, announced the discovery of four new black-hole collisions, measured in the gravity waves given off by those titanic wrecks.
That’s hot stuff: the report of the first gravity-wave detection came just two years ago, paying off a prediction first made (tentatively) by Albert Einstein almost exactly a century earlier in his general theory of relativity.
In its most compact form the general theory boils down to a single equation, just one short line of symbols. The quip is that in relativity, it all boils down to space and time telling matter and energy where to go, while energy and matter tell spacetime what shape to be. A gravity wave is that joke in action: matter-energy in violent motion jostles spacetime into waves we can, only in the last few years, actually see.
This is a series that I've been thinking about for a while. I'm not sure why. It's really meant to be a survey of life on earth, how it originated and how it developed, but I felt like I should start at the beginning.
The most widely accepted theory of the origins of the universe at this point is the Big Bang Theory: there was a point of very high density and very high temperature which developed an instability and exploded, creating the universe, about 13.8 billion years ago. It wasn't really the universe as we know it at that point, because it was very, very hot, but eventually it cooled enough to allow the formation of things like subatomic particles. Then gravity and the other major forces took over, and we have, first, atoms, then stars. Our sun was one of those stars. Here's what seems to be a pretty accurate exposition of the theory, at Wikipedia. And as you can see from this video, it wasn't really all that straightforward.
In Einstein's formulation, the laws of physics actually break before the singularity is reached. But scientists extrapolate backward as if the physics equations still hold, said Robert Brandenberger, a theoretical cosmologist at McGill University in Montreal, who was not involved in the study.
"So when we say that the universe begins with a big bang, we really have no right to say that," Brandenberger told Live Science.
There are other problems brewing in physics — namely, that the two most dominant theories, quantum mechanics and general relativity, can't be reconciled.
Quantum mechanics says that the behavior of tiny subatomic particles is fundamentally uncertain. This is at odds with Einstein's general relativity, which is deterministic, meaning that once all the natural laws are known, the future is completely predetermined by the past, Das said.
And neither theory explains what dark matter, an invisible form of matter that exerts a gravitational pull on ordinary matter but cannot be detected by most telescopes, is made of.
I sort of like this idea -- considering that most of the world's religious traditions assume that the earth and the universe are cyclic, with no beginning and no end . . . well, food for thought, at the very least.
At any rate, starting about 13.5 billion years ago, we have stars. The sun was one of those stars, formed about 4.5-5 billion years ago in a cloud of molecules -- mostly hydrogen, with a little helium and some heavier elements thrown in for fun. Some of those molecules began to attract each other -- gravity again -- and as the group got bigger, the pull became stronger, pulling in more molecules until, finally, we had ignition. At the core of the sun the pressure and temperature are so intense that we have, in effect, a really, really big fusion reactor.
Now, there was still a lot of dust and gas around the sun, mostly forming a big disc, which contained not only hydrogen and helium, but also heavier elements -- remember, other fusion reactors -- stars -- had been burning merrily along for 8 or 9 billion years, and some had exploded after converting the lighter elements into heavier elements -- carbon, oxygen, iron, nickel, all the way up to uranium: the building blocks of planets.
The creation of the earth was undoubtedly a lot more spectacular than the creation of the sun -- lots of crashing and explosions as actual rocks collided and stuck together.
Here's Neil deGrasse Tyson with a description of the process:
Pretty neat, huh?
So, now we have a sun and a planet -- a whole solar system, actually (well, OK, a whole universe, but for this we're keeping it local) -- so where do we go from here? Well, life, of course. After all, that's what we're most interested in. But we need to wait about a billion years, for things to calm down a little bit, so that's for next time.
The universe may have existed forever, according to a new model that applies quantum correction terms to complement Einstein's theory of general relativity. The model may also account for dark matter and dark energy, resolving multiple problems at once.
The widely accepted age of the universe, as estimated by general relativity, is 13.8 billion years. In the beginning, everything in existence is thought to have occupied a single infinitely dense point, or singularity. Only after this point began to expand in a "Big Bang" did the universe officially begin. . . .
"The Big Bang singularity is the most serious problem of general relativity because the laws of physics appear to break down there," Ahmed Farag Ali at Benha University and the Zewail City of Science and Technology, both in Egypt, told Phys.org.
Ali and coauthor Saurya Das at the University of Lethbridge in Alberta, Canada, have shown in a paper published in Physics Letters B that the Big Bang singularity can be resolved by their new model in which the universe has no beginning and no end.
This will, of course, cause creationist/literalist heads to explode all over the place -- after all, they have enough trouble with the Big Bang, since it contradicts their idea of creatio ex nihilo. I find it fascinating as a commentary on how our way of looking at the universe depends on our preconceptions. The prevailing mode of thought in the West, which has been largely shaped by Christianity, sees history as linear: it has a beginning, it runs its course for a certain period of time, and then it ends. Existence becomes a one-off.
Most other traditions see the universe and its history as cyclic, this existence one of a series of similar existences stretching through time with no real beginning and no real end. Granted, some of them see the cycle in more or less dramatic terms -- Hindu mythology foresees a cataclysm that marks the end of our existence -- and then it starts all over again. The Indians of the American Southwest, on the other hand, see a much more peaceable transition: we all came here from another world, probably underground. Even the Norse, as grim as their mythology could be, foresaw Ragnarok, the final war, as the beginning of the transition to the next cycle: Baldur would be resurrected and would lead the few human beings who escaped the destruction into a new, peaceful world.
At any rate, the article is fascinating, if you're into theories on the origin of the universe -- or even if you're not.
Which is the way I normally state the position taken in this post by Tom Sullivan at Hullabaloo. He starts off:
Psychologists at the Yale Mind and Development Lab explore the human tendency to believe that "everything happens for a reason."
We look for causes. I don't really know if this is hard-wired or the results of millennia of conditioning, but we do. From the article he cites:
This tendency to see meaning in life events seems to reflect a more general aspect of human nature: our powerful drive to reason in psychological terms, to make sense of events and situations by appealing to goals, desires and intentions. This drive serves us well when we think about the actions of other people, who actually possess these psychological states, because it helps us figure out why people behave as they do and to respond appropriately. But it can lead us into error when we overextend it, causing us to infer psychological states even when none exist. This fosters the illusion that the world itself is full of purpose and design.
I take this as the basis of our tendency to personify animals and objects, to ascribe meanings and motivations that may or may not there. (In the case of animals, probably, although we may not really understand their motivations, which is one reason birds fascinate me: they're sometimes fairly inscrutable, such as when a whole flock just suddenly takes wing for no apparent reason. And cats are the masters of inscrutability. Objects? Not so much.) Ultimately, it's the basis of religion: natural phenomena become persons of great power and sometimes inscrutable motives -- gods and spirits. (The article notes that many people believe this tendency is the result of religious belief. It's actually the other way around.)
The consequences can be devastating:
Whatever the origin of our belief in life’s meaning, it might seem to be a blessing. Some people find it reassuring to think that there really are no accidents, that what happens to us — including the most terrible of events — reflects an unfolding plan. But the belief also has some ugly consequences. It tilts us toward the view that the world is a fundamentally fair place, where goodness is rewarded and badness punished. It can lead us to blame those who suffer from disease and who are victims of crimes, and it can motivate a reflexive bias in favor of the status quo — seeing poverty, inequality and oppression as reflecting the workings of a deep and meaningful plan.
I'm not sure that these are the best examples -- poverty, inequality, and oppression are not random events: there are human actors involved somewhere along the line. (Just think about the increase in poverty and the steady decline in the standard of living for most of us in the richest country on earth. Sorry, that didn't just happen.) But for victims of natural disasters and just plain old accidents, the conclusion can hold true. In Sullivan's words,"$#!+ happens." For a religious believer, "It's God's will," whatever variety of god you happen to believe in.
There. That should be something to chew on for a while. And do click through and read Sullivan's post. It's not terribly long, but it's incisive.
Scientists at MIT have traced 13 billion years of galaxy evolution, from shortly after the Big Bang to the present day. Their simulation, named Illustris, captures both the massive scale of the Universe and the intriguing variety of galaxies -- something previous modelers have struggled to do. It produces a Universe that looks remarkably similar to what we see through our telescopes, giving us greater confidence in our understanding of the Universe, from the laws of physics to our theories about galaxy formation.
This is what it's describing:
It's fascinating, but the video moves a little too fast for me to follow very well. If you want more information, the research paper itself is here; it's behind a paywall, but you can read the Nature article about the project here. And via Towleroad, here's a rather more accessible discussion of the creation of the model at The Guardian.
It's like I've always said: The universe is a fascinating place.
How long? Maybe 12 billion years. Not long after the Big Bang. And how far away? I have no idea. But it's quite a distance. The image is from the Hubble Space Telescope, and uses gravity as a lense to magnify very faint, very distant galaxies.
"The Frontier Fields is an experiment; can we use Hubble's exquisite image quality and Einstein's theory of General Relativity to search for the first galaxies?" said Space Telescope Science Institute Director Matt Mountain. "With the other Great Observatories, we are undertaking an ambitious joint program to use galaxy clusters to explore the first billion years of the universe's history."
Simultaneous observations of this field are being done with NASA's two other Great Observatories, the Spitzer Space Telescope and the Chandra X-ray Observatory. The assembly of all this multispectral information is expected to provide new insights into the origin and evolution of galaxies and their accompanying black holes.
Somehow, I find it hard to think of myself as the center of the universe.
The earth may be heavier than we thought, because of dark matter. Maybe.
There may be a giant ring of dark matter invisibly encircling the Earth, increasing its mass and pulling much harder on orbiting satellites than anything invisible should pull, according to preliminary research from a scientist specializing the physics of GPS signaling and satellite engineering.
The dark-matter belt around the Earth could represent the beginning of a radically new understanding of how dark matter works and how it affects the human universe, or it could be something perfectly valid but less exciting despite having been written up by New Scientist and spreading to the rest of the geek universe on the basis of a single oral presentation of preliminary research at a meeting of the American Geophysical Union in December.
This is all still very iffy -- dark matter as a concept is relatively new, and was actually invented to explain anomalies between the universe's actual rate of expansion against what our calculations show it should be.
Dark matter – invisible and so-far almost undetectable – was invented to try to explain why the universe does seem to be expanding from a single point as Big Bang theory predicts, but not nearly as fast as it should.
Galaxies, stars and other matter should only crawl away from each other at the speeds we see if there were a lot more gravity holding them back than there would be if the matter we could see were all the matter in the universe.
Making the math work – getting it to agree with what the universe had already decided to do – meant bumping up the guesstimated weight of the universe by 80 percent, with nothing to explain what all that mass actually was. Dark matter is widely accepted as real among physicists, but is still more a mystery filler substance than an actual, explainable phenomenon.
The actual numbers are, to a layman, miniscule, but to a physicist, they're significant. As for dark matter itself, it helps if you think of it as loose neutrinos and such that aren't coalescing into anything really detectable (except, as in this case, by inference).
So, if those holiday treats took up residence around your waistline, just blame it on dark matter.
I was going to post a picture to go with this, but the thing is, you can't see the stuff.
Well, OK, not exactly on the stars, but on a comet. OK, not exactly walking on it, but landing a rocket ship on it. That's what's going to happen next year, if all goes according to plan:
At precisely 10am GMT on 20 January next year, a tiny electronic chip inside Europe's Rosetta spacecraft will flicker into life. The robot probe will then be several hundred million miles from Earth, an orbit that will be bringing it closer and closer to Comet 67P/Churyumov-Gerasimenko, a massive ball of ice, dust and organic materials that orbits the Sun every six and a half years.
Rosetta's electronic wakeup call will trigger circuits, heaters and instruments and bring the probe, which has been in hibernation for two and a half years, slowly back to life in preparation for its landing on the comet, one of the most spectacular feats of space exploration ever planned.
An artist's impression of Rosetta on the surface of its target comet. Photograph: J. Huart/Corbis
You may not think this is all that exciting, but it is:
Then, as the comet – which is about 2.5 miles wide – makes its closest approach to the Sun in August 2015, Rosetta will analyse the plumes of water vapour and gas and the geysers of organic material that will erupt into space as 67P/Churyumov-Gerasimenko heats up and sends out a great glowing tail of gas and filaments behind it.
"Rosetta is going to be the first spacecraft to track the life of a comet as it arcs towards the Sun," says Paolo Ferri, head of solar and planetary operations for the space agency. The resulting data and images promise to be dramatic, to say the least.
We stand to learn a hell of a lot about what the solar system was like on Day One. That's really exciting.
NASA has made a video of what Mars looked like four billion years ago. A little craggier, not so worn down, but not much different than it looks today -- give or take the oceans.
If you were expecting lush greenery, stop and think a minute -- four billion years ago, there wasn't life on Earth yet. In fact, Earth probably looked a lot like Mars. One thing -- the article mentions an "oxygen-rich atmosphere" a billion years before Earth's developed. Last I heard, free oxygen on Earth was the byproduct of early bacteria, causing the first mass extinction -- everything before that was anaerobic. So I wonder what produced the oxygen on Mars.
The Kepler Space Telescope has been in orbit looking for planets around other stars since 2009, and it's started to find some startlingly interesting solar systems out there.
Today, the Kepler team announced the discovery of star system Kepler 62, a group of five planets circling a red star, two of which may be capable of supporting life. That doubles the number of Earth-like planets in the habitable zone that Kepler has confirmed in the cosmos. And they're the smallest, and therefore closest to Earth size, that astronomers have detected. The system is 1,200 light years away.
It occurs to me that even having to ask the question of whether there are other planets in the universe that can support life reveals a tremendously self-absorbed world view. Offhand, I can't think of any reason to suppose that there aren't. It's sort of exciting to have it confirmed, but really, what did anyone expect? I know, I'm dealing with meta-text here -- the assumptions underlying the story. I also realize that not everyone thinks that way, but too many do, particularly in this country. If you go to the comments at the article, someone else also brought that up.
Question of the day: What happened to Kepler-62a?
Via Anel Viz at Nick's Place.
(Footnote: Sorry about the size of the image. Blogger seems to have decided on a one-size-fits-all policy for jpegs, and I can't figure out a way to resize it. Even if I change the size on the file, it still crams it into that itty bitty format.)
Well, not so little -- it's about the size of Jupiter, but much heavier:
Montreal astronomers have found a lonely planet drifting through space without a solar system to call home.
It is 130 light-years from Earth, four light-years from the nearest star, in a region so dark it's invisible to ordinary telescopes.
But the new "rogue" planet, called CFBDSIR2149, gave away its position because it is warm - about 400 C - and heat shows up on infrared telescopes. . . .
The new planet is about the size of Jupiter, but it's believed to weigh between four and seven times more than Jupiter. The astronomers think it has a rocky centre surrounded by dense gas, which is the source of its heat.
An absolutely fascinating article from PBS on what the earth sounds like, with sound track. I can't embed the MP3, so you'll have to follow the link to listen, but do that -- amazing.
Update: If it looks like the galaxy in the center of the video is "eating" other star clusters and small galaxies, that's because it is. Check out this article at Science Daily:
"The Milky Way is constantly gobbling up small galaxies and star clusters," said Ana Bonaca, a Yale graduate student and lead author of a study forthcoming in Astrophysical Journal Letters. "The more powerful gravity of our Milky Way pulls these objects apart and their stars then become part of the Milky Way itself."
Nope, not an idea for a new James Bond flick -- it's an actual world, and not all that far away.
Move over, Hope Diamond. The most famous gems on Earth have new competition in the form of a planet made largely of diamond, astronomers say.
The alien planet, a so-called "super-Earth," is called 55 Cancri e and was discovered in 2004 around a nearby star in our Milky Way galaxy. After estimating the planet's mass and radius, and studying its host star's composition, scientists now say the rocky world is composed mainly of carbon (in the form of diamond and graphite), as well as iron, silicon carbide, and potentially silicates.
At least a third of the planet's mass is likely pure diamond.
