A new image from the Very Large Telescope in Chile shows what resembles a diamond ring in space.
The ring — which appears blue in the image above — is actually the ghostly outer remnant of a dead star. This field of gas, known as Abell 33, is so big that it would take light three years to pass from one side of it to the other.
A star’s glow comes from the fusion of densely packed atoms. Gravity holds this ball of atoms closely together. At the same time, those fusion reactions try to push the ball apart. The star lives in a sort of balance as long as there is enough fuel to keep gravity from making its ball of atoms collapse in on itself. And for the average sun-size star, those fusion reactions may sustain a star in glowing health for some 10 billion years.
But a star won’t live forever. Once most of its fuel has burned up, gravity will allow the star’s denser core to collapse, creating a far denser mix of its heavier elements. When this happens in small to medium-size stars, like our sun, there will be no explosive supernova fireworks. Instead, the star will lose hold of its outer, lighter constituents. Now freed, these gases can begin to slowly drift away as a gently expanding — and glowing — cloud. Astronomers refer to that cloud as a planetary nebula.
And that’s the blue bubble seen here. This nebula resides about 2,500 light-years away in the Hydra constellation.
The denser core of Abell 33’s former star contracted to create a white dwarf, an intensely hot and dense object. Some of the light glowing from it — invisible to the human eye — exists in the ultraviolet part of the electromagnetic spectrum. When this UV light hits oxygen ions in the surrounding planetary nebula, that halo will glow blue (as seen here).
What about the brilliant star in this “diamond-ring setting?” It appears to be perched on the edge of the nebula. It isn’t. That star is only about one-third as far from Earth as the nebula. Only because of a chance alignment do the two appear linked.
atom The basic unit of a chemical element. Atoms are made up of a dense nucleus that contains positively charged protons and neutrally charged neutrons. The nucleus is orbited by a cloud of negatively charged electrons.
constellation Patterns formed by prominent stars that lie close to each other in the night sky. Modern astronomers divide the sky into 88 constellations, 12 of which (known as the zodiac) lie along the sun’s path through the sky over the course of a year. Cancri, the original Greek name for the constellation Cancer, is one of those 12 zodiac constellations.
electromagnetic spectrum The range of radiation that spans from gamma- and X-rays through visible light and on to radio waves. Each type of radiation within the spectrum typically is classified by its wavelength.
fusion The merging of two things to form a new combined entity. (in physics) The process of forcing together the nuclei of atoms. This nuclear fusion is the phenomenon that powers the sun and other stars, producing heat and forging the creation of new, larger elements.
gravity The attraction between any two objects with mass. The more mass there is, the more gravity.
light-year The distance light travels in a year, about 9.48 trillion kilometers (almost 6 trillion miles). To get some idea of this length, imagine a rope long enough to wrap around the Earth. It would be a little over 40,000 kilometers (24,900 miles) long. Lay it out straight. Now lay another 236 more that are the same length, end-to-end, right after the first. The total distance they now span would equal one light-year.
ion An atom or molecule with an electric charge due to the loss or gain of one or more electrons.
planetary nebula A shell of gas ejected from stars like our sun at the end of their lifetimes. This gas continues to expand away from the remaining star (a white dwarf).
star Thebasic building block from which galaxies are made. Stars develop when gravity compacts clouds of gas. When they become dense enough to sustain nuclear-fusion reactions, stars will emit light and sometimes other forms of electromagnetic radiation. The sun is our closest star.
sun The star at the center of Earth’s solar system. It’s an average size star about 26,000 light-years from the center of the Milky Way galaxy.
supernova (plural: supernovae or supernovas) A massive star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass.
A rare but serious virus infection has emerged in the central United States, a team of doctors has just reported. The virus causes fever, a drop in the blood’s infection-fighting white cells and a reduction in the blood’s clot-making platelets. Called Heartland disease, its name honors the Heartland Regional Medical Center in St. Joseph, Mo. That’s where the first men infected with the virus were treated. To date, there have been eight confirmed cases.
Researchers outline how the mystery disease was discovered in the March 28 Morbidity and Mortality Weekly Report. They also describe the potential impacts of the virus. Seven men became very sick with the disease but recovered. The eighth man died, the scientists report, although he had also been sick with other conditions.
The disease was first noticed in June 2009. That’s when two Missouri farmers came to the hospital with severe flu-like symptoms. They reported headaches, nausea, high fevers, diarrhea and gut-distress. And they were very, very tired. Blood tests showed the men had low white-blood-cell counts.
Both men reported they had been recently bitten by ticks. The first man said his wife used tweezers to remove a tick from the trunk of his body the day before his fever began. The second farmer had been “ticked” liberally. He told doctors he had averaged 20 tick bites a day for almost two weeks. His last tick bite had been about three days before his fever struck.
Ticks spread many diseases, so the doctors tested for common ones. Their tests didn’t turn up anything. The men were clearly quite sick, though. And they had lots of changes in their blood that indicated their bodies were fighting severe infections. Antibiotics failed to help. But that’s not surprising as it turns out that both men were infected with a virus. Viruses aren’t affected by antibiotics.
Local doctors alerted the Centers for Disease Control and Prevention. Experts at this CDC found the virus — and confirmed it was a new one. The virus was also an unusual type, a phlebovirus (FLEE bo VI russ). Flies, mosquitoes and ticks tend to spread this kind of germ — but this type of virus had never been seen in the United States. So the Missouri patients had the first American phlebovirus disease. Laura McMullan of the CDC and her colleagues described the unusual germ in the Aug. 30, 2012,New England Journal of Medicine.
Although doctors suspected the virus came from the bite of an infected tick, they couldn’t be sure. So Harry Savage of the CDC in Fort Collins, Colo., and his colleagues stepped in.
They hunted ticks at 12 sites, including the farms belonging to the first two Missouri patients. In all, they collected 56,428 of the tiny animals. There were three different species of ticks in their collection. But only the Lone Star ticks (Amblyomma americanum), named for the bright yellow emblem on their backs, hosted any of the new virus. The Savage team reported its findings last July 22 in the American Journal of Tropical Medicine and Hygiene.
As this work was going on, another six cases of Heartland disease were confirmed; five in Missouri and one in Tennessee. All the patients were men aged 50 or older (as the first farmers had been). Five recalled having tick bites in the days right before their symptoms developed. And all worked outdoors or engaged in frequent outdoorsy hobbies, such as gardening, hunting or hiking.
It took time, but seven of the infected men, including the two first diagnosed with the disease, eventually recovered.
“No vaccine or medication is available to prevent or treat Heartland virus disease,” notes Daniel Pastula of the CDC in Fort Collins and his team in their new report. So the only way to be protected from the disease is by preventing exposure to it. The CDC doctors recommend applying insect repellents when going into bushy or wooded grounds. They also suggest wearing long sleeves and pants — and checking for signs of ticks every time you come in from woodsy sites.
Google announced in January that it was developing a smart contact lens that could continually monitor blood glucose levels of Type 2 diabetics. It has been announced that Google is also working to create a contact lens with an integrated camera that would help people with visual disabilities.
The lens is meant to work like this: a small camera will be embedded out of the way of the pupil so it will not obstruct vision. Blinking activates the sensor for the camera. An advantage to using this lens instead of something like Google Glass is that the camera is able to follow the eye’s precise movement. Even the smallest sideways glance will still allow the camera to face the point of interest. The data collected by the camera can be processed to recognize a variety of properties including faces, motion, color, light, and certain objects.
If someone with a visual impairment is wearing the lenses and is, say, about to step off the curb while there is traffic present. The lens, which can be linked to a smartphone, will give an auditory warning for the wearer to stop, and then let the user know when it is safe to cross. The facial recognition could help the wearer identify friends and family by connecting to a database. There is also the potential for law enforcement to use the technology to spot persons of interest or those with outstanding warrants.
Of course, the lens isn’t only for those who need help visually navigating their surroundings. It will also be able to take regular pictures hands free. The developers also hope to be able to zoom the camera in, reducing the need for binoculars. While this does seem pretty handy in some circumstances, it seems fairly creepy for others. Keep your blinds closed, guys.
At this stage, the lens is still theoretical, but a patent application was filed on the design back in 2012. There is no telling when or if this product will be available on the open market.