The Hubble Space Telescope has given us the deepest view of space ever.
Called the eXtreme Deep Field, or XDF, it’s a composite of more than 2,000 photos taken by Hubble over 10 years.
“The XDF is the deepest image of the sky ever obtained and reveals the faintest and most distant galaxies ever seen. XDF allows us to explore further back in time than ever before,” said Garth Illingworth of the University of California at Santa Cruz, principal investigator of the Hubble Ultra Deep Field 2009 (HUDF09) program.
Hubble’s Advanced Camera for Surveys and its Wide Field Camera 3 focused on a tiny spot of the southern sky, which was found in the center of the original Hubble Ultra Deep Field (UDF), a composite created from Hubble Space Telescope data gathered from 2003 and 2004.
While the images that made up the UDF revealed thousands of near and very distant galaxies, the newly released full-color XDF image reaches much fainter galaxies. NASA scientists say the new XDF also contains about 5,500 galaxies which were taken within a smaller field of view than the UDF.
In creating the XDF, astronomers were able to use very deep exposures in red light taken by Hubble’s new infrared camera, which was installed by the Space Shuttle Atlantis in 2009. The data and images taken by the new camera will allow astronomers to study some of the earliest galaxies in the universe. The faintest galaxies in the XDF are one ten-billionth the brightness of what the human eye can see, according to NASA.
The XDF not only provides a unique view of some of the deepest recesses of space but also serves as a “time tunnel into the distant past.”
The universe is believed to be 13.7 billion years old, and the XDF shows galaxies that go back some 13.2 billion years, less than 500 million years after the Big Bang. The youngest galaxy found in the XDF existed just 450 million years after the birth of the universe.
The XDF will give astronomers the opportunity to view and study those ancient galaxies when they were young, small and growing.
If you would like to learn more about the eXtreme Deep Field, the Space Telescope Science Institute (STScI), which operates the science program for the Hubble Space Telescope, is inviting the public to an online seminar Thursday, September 27, at 1700 UTC.
Three astronomers from the XDF observing team will describe how they assembled the spectacular image and explain what it tells us about the evolving universe. Participants can send in questions for the panel of experts. To participate, visit hubblesite.org.
This video explains how astronomers meticulously assembled mankind’s deepest view of the universe from combining Hubble Space Telescope exposures taken over the past decade. Guest scientists are Dr. Garth Illingworth and Dr. Marc Postman. (Video: NASA, ESA, and M. Estacion and G. Bacon (STScI))
Are you on a diet but having a hard time resisting that candy bar or cheeseburger? The problem might really be in your head.
Researchers have found that an opium-like chemical produced in the brain might explain why some people overeat sweet and fatty foods.
“This means that the brain has more extensive systems to make individuals want to over consume rewards than previously thought,” says Alexandra DiFeliceantonio of the University of Michigan, Ann Arbor, who led the study. “It may be one reason why over-consumption is a problem today.”
The researchers found a region of the brain called the neostriatum, located near the middle and front of the brain, which is best known for controlling motor movements. It also produces the opiate-like chemical called enkephalin, which DiFeliceantonio says sparks and intensifies the urge to consume pleasant rewards.
To make their findings, DiFeliceantonio and her team injected some of the morphine-like drug directly into the neostriatum of their lab rats. After the injections, the rats were fed candy-coated chocolate. The rodent test subjects ate more than twice the number of chocolates than they would normally have eaten.
The researchers also found the levels of enkephalin – the opium-like chemical manufactured by the neostriatum – surged when the rats began to eat the candy. And while the enkephalins, or comparable drugs, didn’t actually make the rats enjoy the candy more, they did increase their cravings and compulsion to eat them.
“The same brain area we tested here is active when obese people see foods and when drug addicts see drug scenes,” says DiFeliceantonio. “It seems likely that our enkephalin findings in rats mean that this neurotransmitter may drive some forms of overconsumption and addiction in people.”
DiFeliceantonio says the findings reveal a lot about our tendency to binge and could eventually lead to the development a drug that blocks the impulse to overeat.
The Mars rover Curiosity is about to undertake its first major scientific experiment on the Red Planet.Before Curiosity heads off to its primary destination, the foothills of Mount Sharp, scientists want to learn more about the terrain surrounding the rover’s landing site.
The Mars mission team members are fascinated with the geology of the area, according to Rob Manning, the Mars Science Laboratory’s (MSL) chief engineer. They’ve noticed the surface is covered with a type of gravelly material, rocks called cobbles and various collections of compressed soil.
“It may very well be that we’re on a place that has been affected by water in the past, and that’s very exciting because that’s what we had hoped for,” Manning said.
Since landing seven weeks ago, Curiosity (as of 9/19/12) has traveled about 91 meters, approximately the length of an American football field. The rover is now traveling in a different direction toward a location called Glenelg, which lies about 400 meters east-southeast of Curiosity’s landing site.
One type of terrain scientists want to learn more about is a kind of bedrock which could be suitable for eventual drilling by Curiosity.
The next is an area marked by many small craters and scientists believe it might represent an older or harder Martian surface.
The third terrain is similar to the type where the rover landed. It’s of particular interest to team members because they’d like to determine if it contains rocks with the same kind of texture as those found in an area close to the landing site where blasts from the descent stage rocket engines scoured away some of the surface.
On its way to Glenelg this week, the rover came across an unusual pyramid-shaped rock. The rover team is planning to touch this mystery rock with a spectrometer to determine its basic composition. They’ll also use an arm-mounted camera to take close-up photographs. This encounter will likely be the first time the rover uses its robotic arm to touch a Martian rock.
Curiosity will then continue on its voyage to Glenelg, where the team will choose another rock for the rover’s first analysis of powder drilled from interiors of rocks.
Once the rover’s side trip to Glenelg concludes, Curiosity will head toward its primary destination, Mount Sharp, which may take a year or two to reach.
Manning tells us everything on the rover has worked perfectly so far except for one of Curiosity’s wind sensors, which was damaged when Martian pebbles hit it. Since the rover has other wind sensors, the mission should not be impacted.
In fact, the mission is going so well the rover team is amazed everything is working so much better on Mars than it did while undergoing testing here on Earth.
Manning says the rover experienced problem after problem during testing. After seeing the rover perform so well on the Red Planet, the MSL team has concluded Curiosity would rather be on Mars than on its home planet.
And it’s a good thing because Curiosity’s visit there could be extended.
The rover’s older sibling, Opportunity, has continued to roam and examine the planet, long after the planned end of its mission. Manning expects Curiosity will do likewise.
There are several factors which justify that optimism. The rover’s power source, according to Manning, is producing more energy than expected. The team also found the Martian climate is better than was anticipated so the unit doesn’t need as much heating as was first thought. Also, with NASA’s orbiting spacecraft flying overhead, the rover has been able to save a great deal of energy while sending back information, which could allow Curiosity to operate longer.
If Curiosity’s time on Mars is extended, Manning expects the rover to continue its voyage up Mount Sharp, which is made up of various layers of material, with the oldest at the bottom of the mountain and the youngest at its peak.
At each of these layers, Manning says that, there will be an opportunity to look back in time into the Martian geological history. So as long as the rover keeps working and NASA extends its mission, “we will continue going up and explore and explore and there is a chapter, chapter and chapter of books telling us about Mars just ahead of us.”
This weekend on the radio edition of Science World, Rob Manning joins us to provide an update with the latest on Curiosity’s mission.
Check out the right column for scheduled air-times or listen now to the interview below.
A new study suggests brides should not ignore those pre-wedding day jitters.
Women who have doubts right before their nuptials are more likely to have an unhappy marriage and end up in divorce court, according to the report in the Journal of Family Psychology.
“People think everybody has premarital doubts and you don’t have to worry about them,” said Justin Lavner, a UCLA doctoral candidate in psychology and lead author of the study. “We found they are common but not benign. You know yourself, your partner and your relationship better than anybody else does; if you’re feeling nervous about it, pay attention to that. It’s worth exploring what you’re nervous about.”
The UCLA psychologists studied 232 newlywed couples living in the Los Angeles area. The researchers then checked in with the couples every six months for four years to conduct follow-up surveys.
The average age of the husbands studied was 27, while the wives were 25.
In their first interview, the newlyweds were asked, “Were you ever uncertain or hesitant about getting married?” Forty seven percent of the guys said “yes,” while 38 percent of their wives answered in the affirmative.
The psychologists found that, while the ladies had fewer misgivings than their spouses, the doubts they did express were much more telling in predicting trouble after the wedding.
In 36 percent of cases, both husband and wife had no doubts about getting married.
Yet 19 percent of the women who did express pre-wedding doubts ended up divorced four years later, as compared with 8 percent of those who didn’t have doubts.
Among the guys, the 14 percent who said they had premarital uncertainties were in divorce court four years.
By comparison, 9 percent of the men who didn’t have doubts ended up divorced.
One in 10 couples got divorced when only the husband had reservations about getting married. That statistic almost doubles, to 18 percent, when the wife alone had doubts.
But when both spouses expressed doubts about entering into the bonds of matrimony, 20 percent of the couples got divorced.
In fact, doubt proved to be a critical indicator of whether the marriage would succeed, more so than factors such as how satisfied the married couples were with their relationships, whether their parents were divorced, if the couple had lived together before the wedding or had a troubled engagement.
While the psychologists aren’t suggesting doubters should call off their weddings, they do advise couples to sit down and discuss concerns before going any further in the relationship.
“Talk about it and try to work through it,” said Thomas Bradbury, a UCLA psychology professor and co-author of the study. “You hope that the big issues have been addressed before the wedding.”
Since they can’t turn back time to witness the creation of the universe almost 14 billion years ago, scientists are working on the next best thing: creating a virtual universe, starting at the beginning with the Big Bang.
With the help of the world’s third–fastest computer, physicists from the US Department of Energy’s Argonne National Laboratory are developing simulations that will take them on a trip from the origins of the universe until today.
Over the years, scientists have scanned the night skies with telescopes which produced maps of the universe. With the advances in astronomical technology, more details about the cosmos have emerged from these surveys.
Taking data from the best sky surveys and running it through Argonne’s Mira Supercomputer, the team plans to produce some of the largest high-resolution simulations of the distribution of matter in the universe.
Given the improvements in technology, Salman Habib, one of the project leaders, says it makes sense to try to understand the universe on the biggest possible scale.
“In effect, all of science, as you know it, can be studied by looking at the evolution of the universe,” says Habib.
The planned simulation, according to Katrin Heitmann, a co-leader on the project, will include images and movies of the universe at different times. Scientists who use the team’s recreation of the universe for their own cosmological research will be able to gather information taken and measured from the statistics produced by the simulation.
Scientists hope the project will help shed greater light on Dark Matter, a theoretical form of matter scientists believe accounts for much of the total mass in the universe.
Habib points out that we’re used to thinking of space as something static or fixed, but as time progresses new space continues to be created. The expansion of the universe is predicted by Einstein’s general theory of relativity, but that same theory, according to Habib, also states that that expansion should slow down with time.
However, observations made over recent years, including work by winners of the Nobel Prize in Physics in 2011, show the opposite is true, that in fact, the universe is expanding at an accelerated rate.
The cause of this expansion remains a mystery, according to Habib, but a number of scientists think Dark Energy is the force behind the universe’s rapid growth.
The team also hopes to learn more about Dark Energy, the hypothetical form of energy thought to compose about 70 percent of the universe .
According to Habib, scientists are unsure exactly what Dark Energy is.
To help solve this mystery, different models of what Dark Energy could be will be put through the simulation to allow scientists to compare the observational results of each model.
Habib and his colleagues hope their simulations will not only help scientists check various models of Dark Energy, and the properties of Dark Matter, but will also provide a kind of grand picture of the evolution of the universe.
Project leaders Habib and Heitmann join us this weekend on the radio edition of Science World to talk about creating a virtual universe.
Check out the right column for scheduled air-times or listen now to the interview below.
Traffic noise can be hazardous to your health, according to the results of a study published in the American Journal of Preventive Medicine.
Researchers studied noise pollution in Fulton County, Georgia. Their findings suggest many of the community’s residents are exposed to high levels of noise from local road traffic which affects their psychological well being and can disturb their sleep, both of which can have serious health consequences.
Last year, the World Health Organization (WHO) also weighed in on the health hazards of environmental noise, saying it can cause adverse psychosocial and physiological effects on public health. WHO research in Western Europe showed that traffic-related noise was responsible for taking more than one million healthy years of life per year because of ill health, disability or early death.
Fulton County, where the study took place, is an urban area which includes the city of Atlanta and its surrounding suburbs. Like most large American cities, Fulton County is surrounded and crisscrossed with a network of major roadways and interstate highways carrying thousands of motorists each day.
The study focused on Interstate Highway 285, a large highway loop that encircles Atlanta, running around the heart of the county.
Researchers collected data from various points to get an estimate of road traffic noise exposure levels surrounding I-285. This included specific physical and characteristics of the area, the level of vehicle traffic and speed, and the various types of vehicles that traveled the interstate.
Guided by the US Federal Highway Administration’s Traffic Noise Model, researchers created traffic noise maps of their study area for both day and night. They then examined and measured various parameters to determine the possibilities that certain percentages of the populace, who are exposed to varying levels of road traffic noise, would be become highly annoyed or have high levels of sleep disturbance, at any given time.
The small city of College Park, Georgia, about ten miles southwest of Atlanta and surrounded with highways, came in first with the highest percentage of its population being at risk of being most affected by noise pollution. About 11.3 percent of College Park’s daytime population and 3.7 percent of its nighttime population were estimated to be at risk for experiencing either annoyance or sleep disturbance.
Ironically, US Census Bureau data indicates that the greater Atlanta area had the lowest number of households – from among 38 metropolitan areas – reporting the presence of road traffic noise.
“It may be assumed that even more people would be affected in other densely populated areas of the US,” says the study’s co-investigator James Holt, of the U.S. Centers of Disease Control in Atlanta.
India’s space program celebrated an historic milestone Sunday after successfully launching its 100th space mission.
The Indian Space Research Organization (ISRO) put a French satellite and Japanese micro-satellite into polar orbit aboard its Polar Satellite Launch vehicle (PSLV).
The mission’s payload included SPOT 6, an observation satellite from France’s space agency (CNES), and Proiteres, a 15-kg microsatellite built by students and faculty at Japan’s Osaka Institute of Technology (OIT).
ISRO began its venture into space back in April 1975 with the launch of its first satellite, Aryabhata, aboard the Soviet Union’s Cosmos-3M launch vehicle.
Indian Prime Minister Manmohan Singh, an early proponent of India’s space program, witnessed the launch and congratulated ISRO scientists and engineers as well as personnel from France and Japan for the successful launch of their satellites.
“Questions are sometimes asked about whether a poor country like India can afford a space programme and whether the funds spent on space exploration, albeit modest, could be better utilised elsewhere,” Singh said. “This misses the point that a nation’s state of development is finally a product of its technological prowess.”
ISRO’s other key accomplishments include the Chandrayaan-1, India’s first unmanned lunar orbiter/probe, which was launched in 2008. The spacecraft’s Moon Impact Probe was released from the orbiter and sent to crash into the moon’s surface at the Shackleton Crater near the lunar South Pole. The orbiter, meanwhile, circled the moon 3,400 times for 341 days, sending observational data back to Earth.
Looking to the future, the Indian space agency is planning a manned space flight program and another mission to the moon with its planned Chandrayaan-2 spacecraft, featuring a lunar lander/rover.
A few weeks ago, Prime Minister Singh, announced plans for one of its most ambitious projects yet, a mission to the Red Planet with the MangalYaan Mars orbiter.
The Arctic sea ice cover has melted to its lowest extent since satellite observations of it began more than three decades ago, breaking a previous record low set in 2007.
NASA and scientists at the University of Colorado, Boulder report the Arctic sea ice extent – the amount of ice covering the sea surface – fell to 4.10 million square kilometers in Aug. 26, 2012. And, with more days left in the summer melting cycle, they anticipate even more of a loss before the freeze cycle begins at the end of September.
“By itself it’s just a number, and occasionally records are going to get set. But in the context of what’s happened in the last several years and throughout the satellite record, it’s an indication that the Arctic sea ice cover is fundamentally changing,” said Walt Meier, a scientist at the National Snow and Ice Data Center (NSIDC) at the University of Colorado.
Sea ice in the Arctic goes through a regular yearly cycle of growing and melting. While it doesn’t raise sea level, says Meier, it does have an effect on the climate systems through how much energy gets absorbed from the sun.
Since the Arctic sea ice observational record began in 1979, the trend of ice melt went from slow and steady to more significant as time went on.
Over the last 10 years, according to Meier, this trend quickly began to escalate, with record-breaking years of sea ice melt along the way. The significant drop in the amount of Arctic sea ice, says Meier, “is a kind of an exclamation point on the long term trend.”
NSIDC officials say the previous record low, set back in 2007, happened because of a near-perfect summer weather for melting ice.
“The Arctic used to be dominated by multiyear ice, or ice that stayed around for several years,” Meier said. “Now it’s becoming more of a seasonal ice cover and large areas are now prone to melting out in summer.”
Because of this, he said, what’s occurring now is an overall thinning of the multiyear ice cover, as well as a decrease in the seasonal ice cover.
That thinning continues throughout the entire year because the ice in the wintertime is also thinner than it used to be, reflecting what Meier calls “another big change in the Arctic sea ice system.”
Meier worries about changes to the Arctic, and consequently Earth’s weather systems, should this trend of escalated sea ice melt continue.
The sea ice is very reflective, it’s white and reflects most of the sun’s energy, says Meier. Because there is continuous daylight during the Arctic summer, most of that solar energy is reflected back into space; it doesn’t warm things and helps keep the Arctic cool. Meier calls this process not only the Arctic’s “air conditioner,” but also the entire Earth’s “air conditioner” as well.
“As we lose that sea ice in the summertime,” says Meier, “it gets replaced by the ocean which is very dark relative to the sunlight. It absorbs most of that energy, reflects very little of it, and that energy then heats up the ocean, which heats up the atmosphere and makes the entire Arctic warmer than it normally would be without sea ice.”
This causes greater warming, taking what has been the globe’s air conditioner and kind of “draining out the coolant,” says Meier. As a result, the ability and efficiency of that process to help cool the Earth is reduced as more and more sea ice is lost in the summertime.
There has been a sort of climate balance on Earth between cold in the polar areas and warmth in the equatorial regions. The contrast between the polar cold and the equatorial warmth, according to Meier, sets up weather patterns like the jet-stream, ocean currents, storm tracks and where, when and how much it rains.
Changes in either climate system throw off this balance and disrupt weather patterns. There’s not enough data right now to say for sure what the exact impacts these weather changes will bring, but Meier suspects areas that are dependent on predictable weather patterns – such as agriculture and other things needed to help sustain life on Earth – may be affected. It’s possible, he says, that droughts may become harsher or that more flooding will occur.
Accelerated melting could also impact animals, such as polar bears, who make their homes on the Arctic ice. Meier says some of these polar animals will find new habitats to live in, but others will be forced to either adapt to the changing climate conditions or face extinction.
Walt Meier joins us this weekend on the radio edition of Science World. Check out the right column for scheduled air-times or listen now to the interview below.