This is a repository for all cool scientific discussion and fascination. Scientific facts, theories, and overall cool scientific stuff that you'd like to share with others. Stuff that makes you smile and wonder at the amazing shit going on around us, that most people don't notice.
Post pictures, vidoes, stories, or links. Ask questions. Share science.
A brief, blazing burst of radio waves detected by the Arecibo Observatory could herald a turning of the tide for a peculiar class of cosmic signals. Until recently, the signals had only ever been detected by a telescope in Australia, a pattern that fueled doubts about their origin.
Fewer than a dozen of these bursts, lasting for only a few thousandths of a second, have ever been reported. Called “fast radio bursts,” the signals are cosmic enigmas that appear to come from the very, very distant universe. But since the first burst discovery in 2007, scientists have not only wondered what kind of cosmic object could produce such a tremendously bright, short-lived radio pulse – but have disagreed about whether the bursts are even celestial.
“There are more theories than there are bursts,” says West Virginia University astronomer Duncan Lorimer, an author on the paper describing the burst, posted to the arXiv on April 10.
On November 2, 2012, a blast of radio waves collided with the Arecibo Observatory in Puerto Rico, where the world’s largest single-dish radio telescope lives. Rain or shine, day or night, the 305-meter dish collects radio waves from the cosmos, which are then processed into data for scientists to study.
The data gathered at 6:35 am UT revealed a massive, 3-millisecond spike. Unlike the radio blasts emitted by some pulsars, the burst did not recur. It briefly blazed and then disappeared. Called FRB 121102, the burst was very similar to six earlier events that constitute the entire reported population of ultrafast radio bursts – a population that until November 2012 had only been seen by one telescope, in Australia.
But transience is only part of what makes these signals so weird. Their chief peculiarity lies in just how dang far away they seem to be.
Normally, radio waves travel at the speed of light. This means that all the different wavelengths and frequencies of radio waves emitted by the same object – say, a pulsar – should arrive on Earth in one big batch.
But if something is sufficiently far away, that changes. Longer, lower frequency waves traveling through the cosmos have a trickier time getting to Earth. Clouds of ionized interstellar particles – electrons, primarily – form roadblocks that slow and redirect these longer waves, causing them to follow a more sinuous path. As a result, the longer waves arrive just a bit later than their shorter kin – sometimes, the difference is only a fraction of a second.
That delay in arrival times is called “dispersion,” and it lets astronomers estimate how far away the waves are coming from. The longer the delay, the more intergalactic junk that got in the way. And since scientists think they know how much junk there is, they can use the dispersion measurement to approximate a distance, or at least identify whether an object lives inside or outside the Milky Way.
If astronomers are interpreting the bursts’ dispersion measures correctly, then the bursts came from billions and billions of light-years away – in other words, they’re nowhere near our cosmic neighborhood. And nobody knows what they are.
“The sources of the bursts are undoubtedly exotic by normal standards,” Cornell University astronomer Jim Cordes wrote in Science.
The ultrafast pulses take their name from Lorimer, who spotted and described the first burst in 2007. That mysterious signal, estimated to have traveled roughly 3 billion light-years before colliding with Earth, stunned astronomers. Many of them questioned whether it was an artifact produced by the telescope that detected it, the Parkes Observatory’s 64-meter telescope in Australia.
In the years after the discovery, skepticism grew. A new class of terrestrial radio bursts detected by the Parkes telescope in 2010 cast more doubt on the original Lorimer burst. Those Earth-based signals, called perytons, opened the door to the possibility that even if real, the original burst was actually coming from much closer to home.
Another Parkes-detected burst, reported in 2012, didn’t do much to alleviate doubts.
But that summer, a third Lorimer burst was described at the International Astronomical Union’s general assembly in Beijing, China; as it turned out, this burst would be one member of a quartet that astronomers would announce the next year in Science. By the end of July, 2013, the total reported stood at six.
“The discovery of fast radio bursts at the Parkes Observatory, if confirmed at other observatories, would be a monumental discovery, comparable to that of cosmological gamma-ray bursts and even pulsars,” Shrinivas Kulkarni, an astronomer at Caltech, told Scientific American at the time.
Strength in numbers was helping the bursts achieve legitimacy, but there was no escaping that they’d all been detected by the same telescope. And until another observatory saw something similar, skeptics could easily question whether the signals were a product of the telescope and its location, rather than the cosmos.
“In fairness, it’s not a bad question to ask at all,” Lorimer says. “Whenever you make a new discovery, it’s very important to have it confirmed by different groups, using different equipment.”
Now, the Arecibo detection of FRB 121102 strongly suggests the signals are not a Parkes artifact, and furthermore, that they’re not terrestrial in origin.
“I’m certainly very excited to see such a convincing result from another team using a different observatory,” says astronomer Michael Keith of the University of Manchester, who was not involved in the current study.
So the questions astronomers are asking are: How far have the bursts traveled? And what, exactly, are they?
“My hunch has always been that they’re extragalactic,” Lorimer says. “But that’s really nothing more than a hypothesis at this point.”
Overall, the dispersion measures do seem to suggest an extragalactic origin. There are many more electrons between Earth and the bursts than can be explained by the Milky Way’s interstellar electrons; but it’s still possible that intervening nebulas could be clouding the measurement, Kulkarni says. He suggests the signals could be coming from spinning neutron stars known as radio rotating transients, or RRATs, that live in our galaxy and also emit a single pulse.
Because the signals are so brief and bright, they must be coming from a rather dense source, says astronomer Scott Ransom of the National Radio Astronomy Observatory. “That means a compact object – i.e., a neutron star or a black hole – is likely somehow to blame,” he says.
Just what that compact object is has yet to be explained. One theory suggests that giant flares erupting from highly magnetic neutron stars, known as magnetars, cause the bursts. Others suggest the bursts result from colliding neutron stars or black holes, evaporating primordial black holes, large magnetic stars, or are the death spasms produced when massive, slowly spinning neutron stars collapse into black holes. That last object, proposed in 2013, is known as a blitzar.
More observations should help teams pinpoint the bursts’ origin. Already, more detections from Parkes are coming down the pipeline, and Ransom says he’s looking through the Green Bank Telescope’s data for similar signals. But what astronomers are really hoping for is a way to find the bursts in real-time – then, they might be able to identify an optical source, like a host galaxy. In addition to supporting an extragalactic origin, that would also allow scientists to use the bursts to probe the characteristics of the intervening intergalactic medium and its ions.
“We really need to get their precise positions,” Ransom says. “That will let us see where they originate – hopefully in or near other galaxies where we can get their distances.” [Reply]
I guess the live cam onboard the ISS is sort of working now, at least enough to embed this with some confidence that there will actually be something to see. I was checking on this thing all weekend and it was down most of the time:-)
Originally Posted by chefsos:
I guess the live cam onboard the ISS is sort of working now, at least enough to embed this with some confidence that there will actually be something to see. I was checking on this thing all weekend and it was down most of the time:-)
Originally Posted by Mr. Plow:
That's pretty awesome.
It is. But I'm finding you gotta stick with it, because a lot of the time it's just cloud tops we're seeing. And if you blink the day is gone! Dawn, for them, was about an hour ago and now it's dark again. [Reply]
Originally Posted by chefsos:
It is. But I'm finding you gotta stick with it, because a lot of the time it's just cloud tops we're seeing. And if you blink the day is gone! Dawn, for them, was about an hour ago and now it's dark again.
No doubt. I clicked on the bottom link a bit ago and they were over the Atlantic, now they are clear over the Indian and about to pass Australia. [Reply]
The largest known volcano in the solar system. Roughly the size of your mom's ass.
Olympus Mons is the largest volcano in the solar system. The massive Martian mountain towers high above the surrounding plains of the red planet, and may be biding its time until the next eruption.
Characteristics
Found in the Tharsis Montes region near the Martian equator, Olympus Mons is one of a dozen large volcanoes, many of which are ten to a hundred times taller than their terrestrial counterparts. The tallest of them all towers 16 miles (25 kilometers) above the surrounding plains and stretches across 374 miles (624 km) — roughly the size of the state of Arizona.
In comparison, Hawaii's Mauna Loa, the tallest volcano on Earth, rises 6.3 miles (10 km) above the sea floor (but its peak is only 2.6 miles above sea level). The volume contained by Olympus Mons is about a hundred times that of Mauna Loa, and the Hawaiian island chain that houses the Earthly volcano could fit inside its Martian counterpart.
Olympus Mons rises three times higher than Earth's highest mountain, Mount Everest, whose peak is 5.5 miles above sea level.
Olympus Mons is a shield volcano. Rather than violently spewing molten material, shield volcanoes are created by lava slowly flowing down their sides. As a result, the mountain has a low, squat appearance, with an average slope of only 5 percent.
Six collapsed craters, known as calderas, stack on top of one another to create a depression at the summit that is 53 miles wide (85 km). As magma chambers beneath the calderas emptied of lava, most likely during an eruption, the chambers collapsed, no longer able to support the weight of the ground above.
A cliff, or escarpment, surrounds the outer edge of the volcano, reaching as high as 6 miles (10 km) above the surrounding area. (The cliff alone is about as tall as Mauna Loa.) A wide depression surrounds the base of the volcano as its immense weight presses into the crust.
Olympus Mons is still a relatively young volcano. Although it has taken billions of years to form, some regions of the mountain may be only a few million years old, relatively young in the lifetime of the solar system. As such, Olympus Mons may still be an active volcano with the potential to erupt.
The tallest volcano in the solar system may also house rock glaciers — rocky debris frozen in ice. Snow and ice deposits above the base of the shield could result in such glaciers. Water-ice insulated by surface dust may exist near the top of the volcano. The tops of these glaciers may host ridges, furrows, and lobes, and be covered by rocks and boulders, and could be as young as four million years old.
Forming a giant
Why would such a huge volcano form on Mars but not on Earth? Scientists think that the lower surface gravity of the red planet, combined with higher eruption rates, allowed for the lava on Mars to pile up higher.
The presence and absence of tectonic plates could also play an important role in the different kinds of volcanoes. The hot spots of lava under the crust remain in the same location on both planets. On Earth, however, the movement of the crust prevents the steady buildup of lava. The Hawaiian Islands, for instance, formed as a plate drifted over a hot spot. Each eruption created a small island in a different spot.
But Mars has very limited plate movement. Both the hot spot and the crust remain unmoving. When lava flows to the surface, it continues to pile up in a single spot. Instead of a chain of volcanic islands, large volcanoes such as Olympus Mons form. In fact, three other large volcanoes near Olympus Mons are similarly gigantic; if only one of the four volcanoes in the region existed, it would be the tallest feature in the solar system.
The volcanoes in Tharsis Montes are so large that they tower above the seasonal Martian dust storms. Italian astronomer Giovanni Schiaparelli, who studied the Martian surface intensively in the late 19th century, observed the enormous features from Earth using an 8-inch (22 centimeter) telescope. When NASA's Mariner 9 arrived at the red planet in 1971, it was able to pick out the tops of the volcanoes above the storms.
After Russia refused to stand down in its invasion of Ukraine in February of this year, the United States imposed sanctions in disapproval and eliminated a great deal of collaboration between NASA and Roscosmos. The one glaring exemption was missions related to the International Space Station. While the ISS is jointly controlled by the US, Russia, Europe, Japan, and Canada, astronauts depend on Soyuz rockets launched from Russia for access.
Less than a month later, Russia’s Deputy Prime Minister Dmitry Rogozin voiced disapproval of this decision, saying they would go toe-to-toe with US threats and could potentially cut off access to the ISS. He also quipped that the US should deliver its astronauts to the ISS via trampoline. At the time of that announcement, the United States had two astronauts onboard, leaving some to speculate about their fate. Rick Mastracchio returned to Earth just yesterday, but Steven Swanson is still onboard. Gregory Wiseman is currently scheduled to launch to the ISS on May 28 for Expedition 40 and that plan does not appear to have changed.
In the latest development, Rogozin announced yesterday that Russia will no longer supply the rocket engines currently used to launch military satellites. There were threats of disabling 11 US GPS base stations. He also alluded to Russia’s withdrawal from the ISS in 2020, saying it will bar NASA’s entry to the ISS. What’s really at stake here?
Russian rocket engines are used by the United Launch Alliance for their rockets that are used to bring military and defense satellites into space. However, the ULA has stated that they already have enough engines stockpiled to perform the next two years’ worth of launches. Additionally, privately-owned SpaceX already has operational rockets that can be commissioned for use, should the need arise. All of the components for the Falcon 9 rockets are designed and manufactured in the United States. While SpaceX is currently fulfilling a contract with NASA, they are seeking to gain a contract with the Department of Defense as well.
The 11 GPS base stations that Russia is threatening to turn off are used to monitor tectonic plate activity. Without them, it will eliminate many data points necessary for understanding the motions of the plates which need to be accounted for with extreme accuracy. This would be a huge headache to the scientists who use the information to understand earthquakes and volcanos. None of them contribute America’s GPS network and it will not affect military or civilian GPS use at all; just the scientists. Rogozin stated that if the US does not allow their GLONASS base stations to be installed on US soil by the end of summer, the GPS units are getting turned off.
If Russia won’t allow American astronauts to travel to and from the ISS using their spacecraft after 2020, that’s actually not a huge problem despite the fact that NASA cancelled the shuttle program in 2011. SpaceX’s Dragon spacecraft could launch from the US as soon as 2017 with the capability of carrying seven astronauts as once. Orbital Sciences, another privately-owned company, is also working toward delivering humans to a low Earth orbit. However, Orbital Sciences uses a modified Russian NK-33 engine in its Antares rockets.
However, there is one aspect of Rogozin’s statement that deserves considerable pause, and that is his claim that Russia could withdraw from the ISS in 2020, when the US was hoping to utilize the ISS until 2024. The space station is divided into segments: The Russian section that is solely controlled in Moscow is used for docking when bringing crew or cargo onboard, and it is also capable of operating independently. The same cannot be said for US compartments, which is fairly problematic. While the US does have the Interim Control Module that could be used in place of the Russian module, there are some logistical concerns of launching and installing the unit. It is unknown if Russia would actually go so far to completely alienate not just Americans, but the 11 other countries governing the ISS as well.
The bottom line is that this back-and-forth disagreement over Russia’s invasion of Ukraine has nothing to do with scientists, yet those are the people who will suffer the most over all of these sanctions. Since 2001, the International Space Station has been a place where over 200 people from 15 countries have come together in the pursuit of exploration and knowledge, despite any socioeconomic or political differences. Though the US will be able to overcome any roadblocks put into place by Russia, the whole situation is still fairly sad. That said, 2020 is a long way away, and a great number of things could happen before then. We can only hope that common sense will prevail so we can all return to peaceful and productive scientific collaboration. [Reply]
Birds flying into window panes might be the stuff of cartoon comic fodder, but the reality is bleak: Hundreds of millions of birds die from flying into transparent glass every year. Thankfully, science is finally putting a stop to it.
A recent New York Times article gives us a glimpse into the fascinating research being done to save these birds lives. One example of which is the shady, underground tunnel below the Bronx Zoo that's being used as a live testing ground/labyrinth for the tech that will save our flying friends. The Times explains:
At the far end were the adjacent glass panels, illuminated by a daylight simulator. One panel was familiar transparent glass, which contributes to the demise of hundreds of millions of birds who fly into it each year in the United States. The other was bird-friendly glass, featuring white vertical stripes that are supposed to serve as a kind of avian stop sign.
"I'm hoping it flies," [William] Haffey, [an ecology student at Fordham University], said. (The previous test subject, a white-throated sparrow, had simply hopped around inside the tunnel, looking confused.)
But the yellow-rumped warbler, affectionately called a "butter butt" by birders, flew straight through the tunnel and decisively avoided the bird-safe glass, the desired result.
You can't really blame the birds for not being keen to fly; somewhere between 355 million and 988 million birds die every year from crashing into buildings—deaths that could very well be avoided. One type of new glass called Ornilux has proved particularly effective. Each pane is covered in a patterned, ultraviolet reflective coating that, while almost invisible to humans, shows up loud and clear to any passing birds.
Of course, any windows that need lines or visual cues to make themselves bird-friendly aren't exactly beloved by designers and architects. According to The New York Times:
Part of the tests, therefore, involve spreading lines or visual cues out farther to see when they no longer deter birds. Mr. Haffey said that vertical lines are believed to work best at four inches apart, while horizontal lines need to be spaced every two inches.
"We're going to see how far we can stretch the limits," Mr. Haffey said. "The fewer lines you have on the glass, the happier the architects are going to be."
But if it means saving that many birds, we can stand the occasional eyesore. [Reply]
