Astronomers think they've found a way to explain why Ultra Compact Dwarf Galaxies, oddball creations from the early universe, contain so much more mass than their luminosity would explain.
Pavel Kroupa, an astronomer at the University of Bonn in Germany, led a research team that's proposing the unexplained density may actually be a relic of stars that were once packed together a million times more closely than in the solar neighbourhood. The new paper appears in the Monthly Notices of the Royal Astronomical Society.
UCDs were discovered in 1999. At about 60 light years across, they are less than 1/1000th the diameter of the Milky Way - but much more dense. Astronomers have proposed they formed billions of years ago from collisions between normal galaxies. Until now, exotic dark matter has been suggested to explain the 'missing mass.'
Science & Technology
It's well known that Charles Darwin's groundbreaking theory of evolution made many people furious because it contradicted the Biblical view of creation. But few know that it also created problems for Darwin at home with his deeply religious wife, Emma.
Darwin held back the book to avoid offending his wife, said Ruth Padel, the naturalist's great-great-granddaughter. "She said he seemed to be putting God further and further off," Padel said in her north London home. "But they talked it through, and she said, "Don't change any of your ideas for fear of hurting me.'"
The 1859 publication of On the Origin of Species changed scientific thought forever - and generated opposition that continues to this day. It is this elegant explanation of how species evolve through natural selection that makes Darwin's 200th birthday on Feb. 12 such a major event.
Darwin held back the book to avoid offending his wife, said Ruth Padel, the naturalist's great-great-granddaughter. "She said he seemed to be putting God further and further off," Padel said in her north London home. "But they talked it through, and she said, "Don't change any of your ideas for fear of hurting me.'"
The 1859 publication of On the Origin of Species changed scientific thought forever - and generated opposition that continues to this day. It is this elegant explanation of how species evolve through natural selection that makes Darwin's 200th birthday on Feb. 12 such a major event.
Liverpool, UK - A researcher at the University of Liverpool has produced the first modern, comprehensive handbook on Manx Gaelic, a language thought to have died out in the mid 19th Century.
As records detailing the grammatical construction of the language are rare, expert Jennifer Kewley Draskau, at the University's Centre for Manx Studies, used texts dating back to the 15th Century as well as unstructured, informal conversations between fluent native speakers on the Isle on Man. She also studied the 18th Century Manx Bible and modern poetry to produce the handbook, called Practical Manx, a guide to the grammar and morphology of the language.
Manx Gaelic - an off-shoot of Old Irish - virtually died out as community speech when English became the language of trade in the 19th Century. Manx is experiencing a revival and more than 600 people now claim to speak the language. The new study is the first attempt to record and describe the language, and the first time in more than a century that a grammar of Manx has been produced.
As records detailing the grammatical construction of the language are rare, expert Jennifer Kewley Draskau, at the University's Centre for Manx Studies, used texts dating back to the 15th Century as well as unstructured, informal conversations between fluent native speakers on the Isle on Man. She also studied the 18th Century Manx Bible and modern poetry to produce the handbook, called Practical Manx, a guide to the grammar and morphology of the language.
Manx Gaelic - an off-shoot of Old Irish - virtually died out as community speech when English became the language of trade in the 19th Century. Manx is experiencing a revival and more than 600 people now claim to speak the language. The new study is the first attempt to record and describe the language, and the first time in more than a century that a grammar of Manx has been produced.
Currently, diamond is regarded to be the hardest known material in the world. But by considering large compressive pressures under indenters, scientists have calculated that a material called wurtzite boron nitride (w-BN) has a greater indentation strength than diamond. The scientists also calculated that another material, lonsdaleite (also called hexagonal diamond, since it's made of carbon and is similar to diamond), is even stronger than w-BN and 58 percent stronger than diamond, setting a new record.
This analysis marks the first case where a material exceeds diamond in strength under the same loading conditions, explain the study's authors, who are from Shanghai Jiao Tong University and the University of Nevada, Las Vegas. The study is published in a recent issue of Physical Review Letters.
This analysis marks the first case where a material exceeds diamond in strength under the same loading conditions, explain the study's authors, who are from Shanghai Jiao Tong University and the University of Nevada, Las Vegas. The study is published in a recent issue of Physical Review Letters.
In today's 365 Days of Astronomy podcast, two astronomers from the University of Minnesota discuss Eta Carina, a relatively close enigmatic star in the Carina Nebula. In a sense of great timing, new images also released today from the ESO (European Organisation for Astronomical Research in the Southern Hemisphere) reveal amazing detail in the intricate structures of the Carina Nebula, one of the largest and brightest nebulae in the sky. In addition to the gorgeous picture above, enjoy a pan-able image and a video that zooms in on this nebula (also known as NGC 3372), where strong winds and powerful radiation from an armada of massive stars are creating havoc in the large cloud of dust and gas from which the stars were born.
The Carina Nebula is located about 7,500 light-years away in the constellation of the same name (Carina; the Keel). Spanning about 100 light-years, it is four times larger than the famous Orion Nebula and far brighter. It is an intensive star-forming region with dark lanes of cool dust splitting up the glowing nebula gas that surrounds its many clusters of stars.
The Carina Nebula is located about 7,500 light-years away in the constellation of the same name (Carina; the Keel). Spanning about 100 light-years, it is four times larger than the famous Orion Nebula and far brighter. It is an intensive star-forming region with dark lanes of cool dust splitting up the glowing nebula gas that surrounds its many clusters of stars.
© AP Photo/ESA
This image provided by the European Space Agency shows and artist impression of catalogued objects in low-Earth orbit viewed over the Equator.
This image provided by the European Space Agency shows and artist impression of catalogued objects in low-Earth orbit viewed over the Equator.
NASA said it will take weeks to determine the full magnitude of the unprecedented crash and whether any other satellites or even the Hubble Space Telescope are threatened.
The collision, which occurred nearly 500 miles over Siberia on Tuesday, was the first high-speed impact between two intact spacecraft, NASA officials said.
"We knew this was going to happen eventually," said Mark Matney, an orbital debris scientist at Johnson Space Center in Houston.
NASA believes any risk to the international space station and its three astronauts is low. It orbits about 270 miles below the collision course.
© AP Photo/Gregory Bull
An archeologist works over a skeleton at the site of a mass grave found in a ruined pyramid in Tlateloco neighborhood in Mexico City.
An archeologist works over a skeleton at the site of a mass grave found in a ruined pyramid in Tlateloco neighborhood in Mexico City.
The unusual burial holds the carefully arrayed skeletons of at least 49 adult Indians who were buried in the remains of a pyramid razed by the Spaniards during the 1521 conquest of the Aztec capital.
The pyramid complex, in the city's Tlatelolco square, was the site of the last Indian resistance to the Spaniards during the monthslong battle for the city.
Archaeologist Salvador Guilliem, the leader of the excavation for Mexico's National Institute of Anthropology and History, said the Indians might have been killed during Cortes' war or during one of the uprisings that continued after the conquest.
Guilliem said many burials have been found at the site with the remains of Indians who died during epidemics that swept the Aztec capital in the years after the conquest and killed off much of the Indian population.
But those burials were mostly hurried, haphazard affairs in which remains were jumbled together in pits regardless of age or gender.
© Claire J. Healy
This is a scanning electron micrograph of the scolex (i.e., anterior attachment organ) of Rhinebothrium sp., a tapeworm in the new order Rhinebothriidea.
This is a scanning electron micrograph of the scolex (i.e., anterior attachment organ) of Rhinebothrium sp., a tapeworm in the new order Rhinebothriidea.
The new tapeworm group, an order now dubbed Rhinebothriidea and that includes worms that parasitize stingrays and grow up to a foot long, was established as new to science by Claire J. Healy, a curator at the Royal Ontario Museum in Toronto, and her colleagues.
Infection with a tapeworm is rare in the United States. People are often unaware they are infected, via an animal or water, but symptoms can include abdominal pain, nausea, vomiting, loss of appetite and malnutrition. The treatment is a pill that kills the worm and helps the body expel it.
© Associated Press
Egyptian laborers are seen by a shaft that leads to a burial chamber where eight revealed sarcophagi found inside a 26th Dynasty limestone sarcophagus along with other mummies at the ancient necropolis
Egyptian laborers are seen by a shaft that leads to a burial chamber where eight revealed sarcophagi found inside a 26th Dynasty limestone sarcophagus along with other mummies at the ancient necropolis
Illuminated only by torches and camera lights, Egyptian laborers used crowbars and picks Wednesday to lift the lid off a 2,600-year-old limestone sarcophagus, exposing - for the first time since it was sealed in antiquity - a perfectly preserved mummy.
The mummy, wrapped in dark-stained canvas, is part of Egypt's latest archaeological discovery of a burial chamber 36 feet below ground at the ancient necropolis of Saqqara. The find, made three weeks ago, was publicly announced Monday and shown to reporters for the first time Wednesday.
Egypt's archaeology chief Zahi Hawass has dubbed it a "storeroom for mummies," because it houses eight wooden and limestone sarcophagi as well as at least two dozen mummies.
Hawass led a group of international media Wednesday into the burial chamber, supervising as one person at a time was lowered into the shaft, holding on to a rope-pulled winch turned by workers above ground.
"It's moments like these, seeing something for the first time, that hold all the passion of archaeology," Hawass said after the mummy was unveiled.
Cape Canaveral, Florida ― In an unprecedented space collision, a commercial Iridium communications satellite and a defunct Russian satellite ran into each other Tuesday above northern Siberia, creating a cloud of wreckage, officials said today. The international space station does not appear to be threatened by the debris, they said, but it's not yet clear whether it poses a risk to any other military or civilian satellites.
"They collided at an altitude of 790 kilometers (491 miles) over northern Siberia Tuesday about noon Washington time," said Nicholas Johnson, NASA's chief scientist for orbital debris at the Johnson Space Center in Houston. "The U.S. space surveillance network detected a large number of debris from both objects."
"They collided at an altitude of 790 kilometers (491 miles) over northern Siberia Tuesday about noon Washington time," said Nicholas Johnson, NASA's chief scientist for orbital debris at the Johnson Space Center in Houston. "The U.S. space surveillance network detected a large number of debris from both objects."
