A tiny piece of space junk (a paint fleck) damaged the window of the space shuttle during the STS-7 mission (Photo: NASA Orbital Debris Program Office)
Gene Stansbery, the office’s program manager, says even the smallest fragments of orbital debris can be harmful to spacecraft in orbit around the Earth – such as the ISS and communications and weather satellites we depend on.
Even the tiniest pieces of space trash are dangerous, in part because they’re moving at tremendous speeds, at a velocity of 11 kilometers per second. Early in the space shuttle program, during the STS-7 mission, a tiny paint fleck hurtling through space hit a shuttle window, causing so much damage the entire window had to be replaced.
NASA’s Orbital Debris Program office isn’t the only US agency keeping an eye on wayward space junk. The US Department of Defense, according to Stansbery, has a worldwide network that can track objects, in low Earth orbit, as small as 10 centimeters in size.
Some of space junk has returned to Earth, but it could take decades or even centuries, for other pieces of space debris to do the same. And, predicting just where it will land, is difficult, if not impossible to do.
Gene Stansbery talks more about space junk on this week’s radio edition of “Science World.” Tune in (see right column for scheduled times) or check out the interview below.
Other stories we cover on the “Science World” radio program this week include:
Standing more and sitting less could reduce your chances of dying earlier, according to a study which looked at 200,000 people.
The Sax Institute‘s 45 and Up Study found adults who sat 11 or more hours per day had a 40 percent increased risk of dying in the next three years, as compared with those who stood more and sat for fewer than four hours a day.
People who weren’t physically active – and sat the most – have twice the risk of dying within three years than active people who don’t sit as much.
Among the physically inactive group, those who sat the most had nearly one-third higher chance of dying than those who sat least.
All the cattle on Earth today descended from the same few dozen animals, which were domesticated from wild ox in the Near East some 10,500 years ago, according to the findings of a recent genetic study.
An international team of scientists took DNA from cattle living today and compared it to the bones of domestic cattle excavated from several Iranian archaeological sites.
The archaeological samples were taken from sites located in a region where cattle were first domesticated, not too long after the concept of farming took hold.
After comparing the sequences of DNA, the team found that differences in the DNA could have only taken place if just a small number of animals, approximately 80, were domesticated from the wild ox.
Extreme water pressure is the biggest risk associated with diving down that deep; it’s like having three SUVs sitting on your toe.
Map showing the location of the Challenger Deep in the Mariana Trench (Image: Karl Musser via Wikipedia Commons)
Cameron began his solo voyage to the Challenger Deep – the deepest point of the Mariana trench located about 322 kilometers southwest of Guam – in the western Pacific Ocean on Sunday, March 25 at 1915 UTC.
He made the journey in a specially-designed submarine called Deepsea Challenger. His trip – down some 10.89 km to the deepest of the deep – took about two-and-a-half hours.
Upon reaching the bottom, Cameron said, “All systems OK,” according to a released statement from National Geographic, which participated in the expedition.
Lt. Don Walsh, USN, and Jacques Piccard in the bathyscaphe TRIESTE. (Photo: NOAA Ship Collection)
Cameron was supposed to spend about six hours exploring the bottom of the ocean but it was cut short, to three hours, due to a hydraulic fluid leak.
Cameron described the deepest point on Earth as looking as bleak and barren as the moon, with very little life present, according to National Geographic.
Due to equipment problems, Cameron wasn’t able to grab as many samples on the dive as was hoped for.
Cameron did document the historic trip in High Definition 3D video and still photographs. The video is expected to be part of a feature film that will be released to theaters and broadcast later on the National Geographic Society’s TV Channel.
Cameron’s return trip to the surface, in his bright green submersible, was much quicker than his descent, taking around 70 minutes.
He described it as a heck of a ride.
Designing Human-like Robots
Non-verbal communication such as a look or gaze can say what words can't (Photo: Lee Agas Guang via Flickr/Creative Commons)
When we talk with someone, words aren’t the only thing that impact our listener. Other subtle factors – such as tone of voice, body language and eye contact – also have powerful communicative potential.
Mutlu is leading a team that’s developing and creating various computer algorithms based on how people communicate without words. These algorithms are then used to program devices, like robots, to look and act more human-like, helping to bridge the gap between man and machine.
A person’s gaze is one of the facets of nonverbal communication Mutlu has found to be especially interesting.
“It turns out that gaze tells us all sorts of things about attention, about mental states, about roles in conversations,” he says.
For example, if you focus your gaze on a specific individual while talking to a group of people, it communicates that what’s being said is especially relevant to that individual.
An experiment to help design robotic technologies that improve how people learn, communicate, and work (Photo: Bilge Mutlu)
Research also shows when you finish saying something in a conversation and your gaze is directed to one particular person, that person is likely to take the next turn speaking in the discussion.
These nonverbal cues tell people where our attention is focused and what we mean when we direct a question or comment in a conversation.
When people really mean what they’re saying, they might open up their eyes and look at who they’re talking to and really try to communicate their message or thought through facial and other cues.
To convert these subtle cues of human communication into data and language that can be used by a robot, Mutlu’s team takes a computational approach. They break down each human cue or gesture into minute segments or sub-mechanisms – such as the direction of the eyes versus the direction of the head or how the body is oriented – which can be modeled.
Professor Bilge Mutlu (Photo: University of Wisconsin-Madison)
Then, certain temporal dimensions are added to the model. These characteristics include the length of time a target is looked at and whether the gaze is focused on the face or should be directed elsewhere after a time.
If he’s designing a robot for an educational role, Mutlu incorporates these nonverbal behaviors. The research team has found learning improves when a robot teacher uses these cues, as opposed to a robot that doesn’t have these abilities.
Mutlu’s goal is not to duplicate a human being in robot form, or have them mimic people on a one-to-one basis. He wants to find the key mechanisms which help us communicate effectively, reproduce them in robots, and enable these systems to connect with us in the way we humans communicate with each other.
Professor Bilge Mutlu joins us on this week’s radio edition of “Science World” to talk about how we all stand to benefit from his work. Tune in (see right column for scheduled times) or check out the interview below.
Other stories we cover on the “Science World” radio program this week include:
Strategy to develop safe and effective tuberculosis vaccines unveiled in South Africa
Science Scanner: Astronomers Find Jewel in the Cosmos
False-color image of LEDA 074886 taken with Subaru Telescope's Suprime-Cam. The central contrast has been adjusted to reveal the inner disk/bar-like component. (Image: Dr. Lee Spitler, Swinburne University of Technology, Australia)
Astronomers say they’ve found a jewel in the cosmos.
It’s a rare, rectangular-shaped galaxy, called LEDA 074886, that resembles an emerald-cut diamond.
“It’s one of those things that just makes you smile because it shouldn’t exist, or rather, you don’t expect it to exist,” reports lead author, Alister Graham, in an upcoming edition of the Astrophysical Journal.
The research team says this discovery allows astronomers to obtain useful information for modeling other galaxies.
The astronomers think it’s possible that their “emerald-cut galaxy” may have formed out of the collision of two spiral galaxies and may resemble an inflated disk that is seen side-on, like a short cylinder.
Most of the galaxies in the universe can be found in one of three forms: ellipsoidal, disk-like or irregular.
In their research, the scientists noticed that circulating endothelial cells (CEC) in heart attack patients were unusually large and misshapen, making them promising biomarkers for predicting arterial plaque rupture, which can cause a heart attack.
As their test subjects, researchers selected 50 heart attack patients who sought treatment in the emergency rooms of four acute care hospitals in San Diego as their test subjects. Using different cell isolation platforms, the researchers found that the CEC counts and the cell’s structural features in their test subjects were dramatically different compared to those from members of the healthy control group.
“The ability to diagnose an imminent heart attack has long been considered the holy grail of cardiovascular medicine,” said Dr. Eric Topol, the study’s chief investigator.
An estimated 17 million people worldwide, die of heart attacks and stroke each year, most commonly the result of obstructive coronary artery disease, according to the World Health Organization.
Space station might be used to simulate mission to Mars
International Space Station as seen from Space Shuttle Discovery (Photo: NASA)
Looking ahead to a future manned mission to Mars, NASA might use the international space station to help train and prepare astronauts for the long voyage to and from the red planet.
The ISS would be used to conduct a 500-day mock mission to Mars.
At a recent press conference, Mike Suffredini, NASA’s space station program manager, said astronauts will need to spend more than six months in space before they can fly beyond low earth orbit – which is up to 2,000 kilometers (1240 miles) above the Earth’s surface.
There are a number of challenges an astronaut will face in the extended space travel time needed to fly to and from Mars. The simulated mission to Mars will be used to help build the astronaut’s endurance in preparation for the long space trip.
The simulated mission will be patterned after the Mars-500 experiment which also simulated a round-trip journey to Mars. That experiment, which simulated a full-length manned mission and involved a six-person crew from Russia, China and Europe, took place from June 2010 to November 2011 or 520 days.
A Russian cosmonaut who spent 14 months aboard the Mir space station in the 1990s holds the current record for human endurance in space.
While the mock Mars mission isn’t expected to take place for at least two or three years, Suffredini says various physical and psychological issues will need to be addressed before such an ambitious project is even attempted.
With recent budget cuts, the future of NASA’s plans manned exploration is in question and there is debate at the space agency as to where the astronauts should head for.
Right now, there’s consideration for missions to the moon, asteroids and Mars. But, between the costs and the development of the necessary spacecraft needed for such missions, it’s anyone’s guess as to when or where the US manned space program will head to next.
Rejected male fruit-flies turn to the bottle for comfort
Male Drosophila melanogaster fruit-fly (Photo:André Karwath via Wikimedia Commons)
When a guy’s romantic advances are spurned by a woman, he may turn to alcohol to kill the pain of rejection.
It turns out that male fruit flies do the same thing.
The fruit flies may turn to alcohol in order to satisfy a physiological need for a reward when they are deprived of sex, according to a new study from the University of Missouri.
Understanding the reasons rejected male flies find comfort in ethanol could help lead to treatments for human addictions, says lead researcher Troy Zars.
The study revealed male fruit flies that repeatedly mated for several days didn’t show a particular fondness for food spiked with alcohol. However, the males who were spurned or denied access to the female were found to strongly prefer their food mixed with 15 percent alcohol.
Zars’ team believes the alcohol may satisfy the flies’ desire for physical reward.
“Identifying the molecular and genetic mechanisms controlling the demand for reward in fruit flies could potentially influence our understanding of drug and alcohol abuse in humans,” Zars says, “since previous studies have detailed similarities between signaling pathways in fruit flies and mammals.”
With the entire release of the sky catalog, the WISE mission has now met its fundamental objective, according to NASA.
The new atlas is made up with more than 18,000 images taken by the WISE mission.
An accompanying catalog lists the infrared properties of more than 560 individual objects, which can be found in the images. Most of the objects listed are stars and galaxies, many of which have never been seen before.
Artist's concept of the Wide-field Infrared Survey Explorer (WISE). (Image: NASA/JPL-Caltech)
“Today, WISE delivers the fruit of 14 years of effort to the astronomical community,” said Edward Wright, WISE principal investigator at UCLA.
The WISE spacecraft launched Dec. 14, 2009. In 2010, it mapped the entire sky using equipment that was much more sensitive than that used on previous missions.
Over the course of its mission, WISE collected more than 2.7 million images of everything from asteroids to distant galaxies.
The mission team has also been processing more than 15 terabytes of data transmitted back to Earth by the WISE spacecraft.
About a year ago, in a preliminary release, NASA offered its first bundle of WISE data to astronomers.
The observations made so far by WISE have led to a number of remarkable finds, including the discovery of a class of stars with temperatures as cool as the human body.
Astronomers had been on the lookout for these elusive stars for more than a decade. Called Y-dwarfs, the stars have been cooling ever since they first formed. Unlike other, much hotter stars, they don’t shine in visible light and couldn’t be seen until the WISE mission used its infrared vision to map the sky.
Artist's conception of the first-known Earth Trojan asteroid, discovered by NASA's WISE mission. The asteroid is gray and its extreme orbit is shown in green. Earth's orbit around the sun is indicated by blue dots. (Image: Paul Wiegert, University of Western Ontario, Canada)
WISE made some other surprise discoveries, including what scientists call the first known Trojan asteroid, which shares the same orbit around the sun as the Earth.
A Trojan object, such as this asteroid, assumes the same orbital path of a major space object, such as a planet or a large moon.
But since they sit at points within the orbital path that are approximately 60° ahead of or behind the planet or large moon, there’s no danger of collision.
Given recent concern about asteroids possibly endangering our planet, WISE also pollednear-Earth asteroids, finding many fewer mid-sized objects than previously thought, and that NASA has found more than 90 percent of the largest near-Earth asteroids.
At least 100 papers, based on the results from the WISE survey, already have been published, according to NASA. Now that scientists have access to data from the whole sky, even more discoveries are expected.
Why We Never See the Far Side of the Moon
The moon's near side (left) is covered with dark splotches of lunar maria that look like a man's face when seen from Earth. The moon's far side (right), with its many craters and elevated topography, looks quite different. (Photos: NASA)
Do you ever wonder why we never get to see the far side of the Moon?
New research suggests it’s because of the rate at which the moon’s rotation slowed before locking into its current orientation with Earth.
Artist's drawing of body hitting young earth to form our moon (Artwork: Joe Tucciarone)
Something hit our planet long ago, ripping a big chunk of Earth out. Some of that original impact material collected together under its own gravity and orbit to form the moon.
When that happened, according to Aharonson, the moon was closer to Earth and it spun a lot faster.
If anyone was on Earth at the time, they’d have looked up and seen different sides of the moon on different nights, rather than the same static view we see today.
So what caused the moon’s rotation to slow down?
Aharonson points to a process called “tidal dissipation.” The moon, as it orbits our planet, raises tides on Earth.
A closer look at the South pole of the far side of the moon as seen from the GRAIL mission’s Ebb spacecraft. (Photo: NASA/JPL-Caltech)
At the same time, Earth also raised tides on the moon, causing it to bulge and change its shape slightly. This also caused the moon to dissipate energy in the form of heat. This process took energy from the rotation of the moon which caused its spin to slow down.
“Like a ballroom dancer, the moon spins around the Earth at exactly the same rate as it spins around itself,” Aharonson says, “so it always maintains the same face towards its companion, Earth.”
Although the moon’s rotation speed has stabilized and is no longer slowing down, its orbit is evolving outward from the Earth, slowly expanding its circuit around our planet.
Right now, it takes the moon around 30 days to orbit the Earth, but in the future, says Aharonson, both the moon and Earth will eventually synchronize to each other. The consequences of this synchronization, according to Aharonson, are that Earth would no longer experience changing tides and we would no longer observe the moon go through its monthly phases.
That’s when we would really see the exact same thing night after night when we look at the moon.
NASA’s GRAIL mission has beamed back its first video of the far side of the moon. The imagery was taken on Jan. 19 by the MoonKAM aboard the mission’s “Ebb” spacecraft.
The process of tidal dissipation has also affected the shape of the moon. Looking at a big bright full moon, we see a perfectly round sphere. But it’s not, according to Aharonson, who says it is actually an ellipsoid, shaped a little like an American football. The moon has three axes and each one of them is a little different.
Why we only see the near side of the moon was not due to random chance, but depended on the two sides of the moon being asymmetrical.
The side facing us is filled with large, dark, basaltic plains formed by ancient volcanic eruptions which are dense as well as low and closer to the moon’s center of mass.
And, with all due respect to the Pink Floyd album “Dark Side of the Moon,” the other side of the moon isn’t really necessarily dark. When it’s illuminated by the sun, it can appear much brighter than the side we see.
Some new and unique views of the moon in this video “tour” from NASA
Its moonscape is quite different, too. It is filled with mountains rather than the basaltic maria and basins of the near side.
If the moon were flipped around, giving us a view of the far side, Aharonson says we’d notice a little bit more mass and, because of its high mountains, it appear to be closer to Earth.
Scientists still don’t know why the moon is so asymmetrical; why one side of the moon is so different than the other.
Dr. Oded Aharonson joins us this weekend on the radio edition of “Science World.” Tune in (see right column for scheduled times) or check out the interview below.
Other stories we cover on the “Science World” radio program this week include:
Science Scanner: Previously-Unknown Stone Age People Discovered
An international team of scientists has discovered a previously-unknown Stone Age people.
The fossils of human remains, found in south-west China, reportedly offer a rare glimpse of a fairly recent stage of human evolution.
The remains of what the scientists call “red-deer” – because they hunted and cooked extinct red deer – were first found in 1979 near the village of Longlin, China. Skeletal remains of three more of these people were found a decade later, in 1989, at Maludong, or Red Deer Cave, near the city of Mengzi in Yunnan Province.
Scientists date the remains to between 11,400 and 14,500 years ago, when farming culture in China first developed. It’s likely these people also shared their early Asian environment with a more modern-looking people.
The fossils are described as the remains of people who had a highly unusual mix of archaic and modern anatomical features. The team says it’s been cautious about classifying the fossils because of the unusual wide range of features.
“These new fossils might be of a previously unknown species, one that survived until the very end of the Ice Age around 11,000 years ago,” says study co-leader Darren Curnoe, of the University of New South Wales, Australia.
According Curnoe, scientists still know little about how modern humans evolved in Asia after our ancestors settled Eurasia some 70,000 years ago.
“The discovery of the red-deer people opens the next chapter in the human evolutionary story – the Asian chapter – and it’s a story that’s just beginning to be told,” says Curnoe.
The researchers studied nearly 1,000 men and women. They say their findings provide the first evidence linking dTFAs to negative behavior, ranging from impatience to overt aggression.
Dietary trans-fatty acids are primarily products of a process called hydrogenation, which is widely used by food producers. It reduces or saturates organic compounds and makes unsaturated oils solid at room temperature. High levels of dTFAs are found in margarine, shortening and various prepared foods.
This is a sampling of workers from an artificially formed hot defensive bee ball. (Photos: Ugajin A, Kiya T, Kunieda T, Ono M, Yoshida T, et al. (2012) Detection of Neural Activity in the Brains of Japanese Honeybee Workers during the Formation of a ‘‘Hot Defensive Bee Ball’’. PLoS ONE 7(3): e32902. doi:10.1371/journal.pone.0032902)
But, according to a new study from two Japanese Universities, the honeybees have developed a unique defense mechanism; they swarm the hornet, creating a “hot defensive bee ball” that literally cooks the hornet.
A robotic handyman aboard the International Space Station, recently proved it can perform intricate and precise satellite-servicing tasks in space.
Dextre at Work (Photo: NASA)
Earlier this month, Dextre, part of Canada’s contribution to the ISS, successfully completed tasks – which were designed to demonstrate the various tools, technologies and techniques needed to refuel and repair satellites robotically – on the space station’s external RRM module.
To prove his worthiness as a repairman, Dextre successfully retrieved and inspected RRM tools, released safety launch locks on tool adapters, and used an RRM tool to cut extremely thin satellite lock wire.
These operations represent the first use of RRM tools in orbit and Dextre’s first participation in a research and development project.
Joining Dextre and the RRM aboard the International Space Station is another robot called Robonaut 2, or R2, the first human-like robot, which was sent up in 2011.
The Moho boundary was named after Andrija Mohorovičić, a Croatian scientist who discovered it back in 1909.
Although this region has never been seen, scientists can spot it through seismic measurements when there are sharp and sudden changes in the speed of earthquake waves, compared to measurements taken within the crust. Scientists presume that this may be due to a change in rock types.
Earth’s crust is the outermost shell of the planet. The crust is important because we live on it and it’s where all our geological resources – such as natural gas, oil and minerals – come from.
The crust and upper mantle layers of the Earth are where major geological processes, like earthquakes and volcanism, take place.
In order to study and understand the Moho, scientists currently use data models based on either seismic or gravity measurements, but those methods can provide limited information.
According to ESA, the new maps make it possible to estimate the Moho depth worldwide, including areas where ground data is not currently available.
What the Massive Japanese Earthquake Sounded Like
People take shelter as a ceiling collapses in a bookstore during the 9.0 magnitude earthquake in northeastern Japan, March 11, 2011 - (Photo: Reuters)
He took the seismic waves, created by the earthquake and its aftershocks, and converted them into audio files, so people can actually hear what the quake sounded like as it traveled through the earth and throughout the world.
“We’re able to bring earthquake data to life by combining seismic auditory and visual information,” said Peng. “People are able to hear pitch and amplitude changes while watching seismic frequency changes. Audiences can relate the earthquake signals to familiar sounds such as thunder, popcorn popping and fireworks.”
Vehicles are crushed by a collapsed wall at a carpark in Mito city in Ibaraki prefecture after a massive earthquake rocked Japan, March 11, 2011 - (Photo: AFP)
Peng says he and his colleagues were motivated to produce the audio representations of the earthquake in order to easily convey the information and scientific knowledge that came out of the event.
While people can generally hear audio between 20 Hz and 20,000 Hz, the actual sounds produced by the earthquake’s seismic data were below the normal range of human hearing.
In order to create an audio representation humans can hear, Peng’s team increased the speed of the data playback until it produced audio that fell within the range of normal human hearing.
The process allowed for a bit of time compression as well, condensing hours of material into just a few seconds.
Clip #1 provides the sound of the main earthquake taking place. The audio was produced from seismic data recorded near the earthquake’s epicenter.
>>> Clip #1
In clip #2, you can not only hear the main earthquake, but the immediate aftershocks as well. Peng says the aftershocks you hear in the clip are actually the sounds of tectonic plates adjusting after the main quake.
>>> Clip #2
Clip #3 was taken from seismic data recorded in California, approximately 9656.064 kilometers away. In this clip, what sounds like thunder is actually the main quake in the distance, and the rainfall sounds are the sounds of subtle fault movements induced by the Japan earthquake.
>>> Clip #3
A seismologist points to a seismographic graph showing the magnitude of the earthquake in Japan, March 11, 2011. (Photo: REUTERS/David Moir)
Soon after Kobe quake, the Japanese government purchased and deployed thousands of high quality seismic instruments across the entire nation. It’s this network of sophisticated measuring devices that made the abundance of data on the 2011 Japan Earthquake possible.
Dr. Zhigang Peng joins us this weekend on the radio edition of “Science World.” He shares more on how he and his research team were able to take raw seismic data and turn it into audio recordings. Tune in (see right column for scheduled times) or check out the interview below.
Other stories we cover on the “Science World” radio program this week include: