Extraterrestrial objects are constantly bombarding Earth; thankfully the vast majority are microscopic.
Thanks to the planet’s atmosphere, we live largely unaware of this celestial fusillade, which averages about 100 tons a day and mostly burns up long before hitting the ground. From the few that do make impact, researchers can gather clues about the composition of our solar system, with the goal of understanding how planets and other bodies emerged from an embryonic disk of dust and gas some 5 billion years ago.
However, it seems many of the samples researchers have to work with originated from a single event that’s been raining fallout for some 466 million years, giving us a biased picture of what’s actually out there.
There’s an army lurking in the underbelly of Twitter.
Legions of fake Twitter accounts, called bots, roam the virtual social media landscape, often wreaking havoc wherever they go. You’ve probably encountered these accounts, those so-called eggheads, in Twitter’s untamed wilderness. They seem drawn to political conversations, but are often used to artificially inflate the number of followers a profile has, send spam and manipulate online sentiment. Herded by shadowy “botmasters,” these accounts can be financially lucrative, especially after they’ve been around for a few years. Read More
The mysterious fairy circles that form regular hexagonal patterns in the Namibian desert have long mystified researchers.
Thousands of bare patches arranged in a grid and measuring anywhere from six to over a hundred feet in diameter speckle the desert throughout the country. A similar phenomenon was recently documented in Western Australia as well. To date, their origin is still unknown — the fairy circles are held to be the footprints of the gods by the native Himba, or the result of noxious dragon breath in another popular tale. Read More
Lasers could turn Earth’s atmosphere into a defensive, or offensive, tool in the future of warfare.
Proposed by BAE Systems, a defense and aerospace company founded in the United Kingdom, the conceptual Laser Developed Atmospheric Lens (LDAL) would use lasers to ionize and heat the atmosphere in a way that temporarily endows small pockets of it with useful characteristics. This could take the form of an aerial lens used to magnify objects far away, or even a kind of refractive shield to scatter incoming enemy laser beams. Read More
In tense situations, everything can change between beats of the heart.
And, it’s more than just the situation that changes — our own reaction to a potentially dangerous encounter can hang on something as simple as the contraction of our heart. In a small study, researchers from the United Kingdom looked at how participant’s perception of a threat changed with the beating of their hearts. The found that people were more likely to exhibit a reaction based on fear when their hearts were pumping blood, as compared to the resting phase between heartbeats. Read More
A deadly mystery lingers in a cave in northern Spain. A sign at the entrance warns visitors not to enter.
For decades, speleologists have trained inside CJ-3, a 164-foot-deep cave in Cañon del Río Lobos Natural Park in the Soria province. But in 2014, visitors to the cave experienced something new at the bottom: they nearly suffocated, and one person fainted. The oxygen levels had suddenly, and inexplicably, dropped.
The unusual incident prompted park officials to contact geologist Raul Perez Lopez of the Geological and Mining Institute in Madrid, Spain. Shortly after the first report, daredevil Perez dove into action. Read More
A massive, bow-shaped wave was spotted for the first time in the highest regions of Venus’ atmosphere, perplexing astronomers.
The structure was captured by the Japan Aerospace Exploration Agency (JAXA) in some of the first images returned by their Akatsuki orbiter following a troubled orbital insertion in late 2015. Using both infrared and UV imaging, researchers spotted the prominent feature in the planet’s upper atmosphere, where winds whip by in excess of 200 miles per hour. Any features spotted in the atmosphere should get carried along by the fierce winds, but this curved wave remained planted firmly in place, lasting for at least four days. Read More
Asteroid impacts have the distinction of being one of the few sci-fi concepts that will definitely happen at some point. But despite the clear and present (although potentially far off) danger of getting smacked by an asteroid, we’ve devoted few resources to averting such a catastrophe.
As Discover reported in 2013, NASA’s budget for such operations makes up only a fraction of their budget, although it has risen in recent years, and it’s unclear how that might change under the Trump Administration. NASA in 2015 ended an agreement that provided non-financial support to the Sentinel mission — designed specifically to pinpoint incoming asteroids — and similar asteroid defense projects are largely dependent on private donations. In a new report, a coalition of federal agencies is making the case to increase support for detection and deflection efforts, laying out a multifaceted, long-term blueprint to defend Earth from rocky invaders.
The interagency working group comprises members of NASA, FEMA, the Department of Defense and the Department of Homeland Security, among others. The coalition convened in January 2016, and its first report was released on the heels of an asteroid impact response simulation conducted by NASA and FEMA in California.
A rock 40 or 50 meters across could take out a city, and something substantially larger — a kilometer or so across — could lay waste to an entire continent. The 2013 Chelyabinsk meteor, just 20 meters across, exploded over Siberia, shattering windows and injuring hundreds as a result. The 1908 Tunguska event, also in Siberia, leveled over 700 square miles of forest and exploded with a force equal to approximately five to 10 megatons of TNT. In both instances, there wasn’t an impact.
Still, there’s a roughly 1 in 100,000 chance that an asteroid will hit Earth will country-leveling force. But Chelyabinsk-size objects, big enough to cause damage, yet small enough to potentially escape detection, are cause for worry. If history is any indicator, we’re due for one of them once or twice a century, and a Tunguska-size event every few centuries.
“The big gaping hole, as pointed out in this report, are asteroids between the size of something only large enough to destroy a city and all the way up to 140 meters,” says Ed Lu, a former astronaut and CEO of B612, a advocacy group focused on asteroid impacts.
Lu points to a space telescope called NEOCAM currently being developed by NASA’s Jet Propulsion Laboratory, to scan the areas of the solar system nearest to Earth. The project was passed over for funding from NASA’s Discovery Program, which would have provided extra support for the mission. The telescope is meant to locate and track smaller asteroids that fall into the 20-140 meter range, and, when it’s completed, will be a complement to the Large Synoptic Survey Telescope currently under construction in Chile, Lu said. LSST is optimized to find smaller objects in our solar system, and is set to begin operations in 2021.
The asteroid defense working group estimates that there are around 10 million near-earth objects 20 meters or smaller, and some 300,000 larger than 40 meters that we don’t know about yet. NASA currently lists only 15,413 near-Earth objects, of which 1,763 are classified as Potentially Hazardous Asteroids.
Says NASA in an emailed statement: “In fiscal year 2010, the NEO Observations Program funded 21 projects to find, track, and characterize near-Earth asteroids. In fiscal year 2016, the program funded 34 individual projects to find, track, and characterize near-Earth asteroids plus nine studies of impact mitigation and deflection strategies and techniques. By October 2016, the number of discovered near-Earth asteroids (NEAs) topped 15,000, with an average of 36 new discoveries added each week. This milestone marked a 50 percent increase in the number of known NEAs since 2013, when discoveries reached 10,000 in August of that year. The discovery rate (number found per year) has increased 83% since 2013.”
The working group crafted a seven-part plan that addresses dangerous asteroids and the potential aftermath of an impact. The full proposal is set to be released at a later, unspecified date.
Their first recommendation: Improve detection and tracking technologies. A space-based observatory dedicated to scanning the solar system for incoming asteroids would be optimal. Theoretically, it would give humanity enough time to hatch a defense plan. The group also called for improved models of asteroid behavior and composition to understand how any objects we find might respond to potential interventions.
Emergency plans for the days leading up to, and following, a collision are also necessary, according to the working group. This entails building an international alert system and a means of coordination between national and international agencies. That means establishing protocols for communication and data sharing between international agencies. The report heavily stresses the primacy of international cooperation in the event of an asteroid impact — such an occurrence would surely require even rival nations to work together for the greater good.
Finally, scientists need to study various ways to deflect an incoming asteroid from its path and save the planet, according to the report. This could take many forms: ramming a spacecraft into the asteroid, breaking it up with nuclear bombs, detonating explosives nearby to partially vaporize it and let the gases push it off course, or even painting parts of it black or white to allow the sun’s light to push it in a different direction.
Getting some practice is also part of the plan: The working group recommended conducting missions to asteroids to test technologies that would enable asteroid herding. This includes a nimble propulsion system, onboard artificial intelligence and monitoring systems for up-to-date assessments of the asteroid.
We’ve already gotten a head-start. In addition to several asteroid rendezvous over the past two decades or so, the OSIRIS-REx mission, launched in September 2016, will make contact with with the asteroid Bennu in August 2018. The goal is to collect samples from Bennu and return them to Earth, a mission that will also test some of the protocols necessary for an asteroid-deflection mission, should it ever become necessary.
But before we get into the deflection business, we need a target. This is why Lu and others are pushing for better detection capabilities now. It could take more than a decade to fully design and equip a mission to coax an asteroid off its path toward Earth, so early warning will be key.
Lu says that projects of this sort need to be viewed as more than just scientific missions, which has often doomed them to funding shortfalls.
“It should not be judged in a pure science competition against other scientific missions with the criteria being how much novel new science you are doing,” he says. “This is really something that is not just science, but it’s really about protecting life.”
The money involved would barely make a dent in NASA’s budget, to say nothing of larger agencies like the Department of Defense.
“We’re talking half a percent of the budget of a small agency like NASA,” Lu says.
The problem may lie in the way that we as humans assess risk. We seem to have a tough time grappling with the consequences of events that we haven’t personally experienced, and sometimes fail to take the necessary precautions. The 2011 Fukushima disaster and the failure of the levees after Hurricane Katrina are prime examples.
“It’s not as small as you think, it’s just that it’s longer than a generation,” Lu says. “If it didn’t happen in your lifetime, you naturally discount it.”
[An earlier version of this story mistakenly stated that NEOCAM was passed over for funding. In fact, it is still being supported by NASA. Discover regrets the error.]
[This post has been updated with comments from NASA]
With a flash of light, researchers have induced mice to pounce on anything in their line of sight.
Researchers from Yale University and the University of São Paulo isolated the regions of the mouse brain that control both hunting and biting, and say they can activate the neurons involved on command. The research should help illuminate another small part of the neural pathways that connect the outside world to our internal computations. Read More
For the first time, a species of bumble bee has been placed on the endangered species list in the United States. In fact, it’s the first bee of any kind in the contiguous 48 states to land on the list.
The rusty patched bumble bee, Bombus affinis, was once prevalent in 28 states in the Midwest, south and north-eastern U.S., but its numbers have been declining since at the least the 1990s, say researchers with the U.S. Fish and Wildlife Service. The agency announced Tuesday that B. affinis had been added to the list, a move that will go into effect February 10. Read More