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Scientists Still At Odds On Tunguska After 100 Years

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© Unknown
Four professors from the University of Bologna, Carlo Stanghellini, Maurizio Serrazanetti, Romano Serra, and Marco Cocchi, believe Lake Cheko was created by a meteorite impact due to its shape and tree growth in the area. The lake is elliptical (approximately 100 meters by 300 meters) rather than round, which is consistent with other lakes and swamps in the area. However, no impact ring or rim residue has been discovered at the lake, which would be noticeable had a meteorite created the lake. The native Evenki say that the lake has always been there and the name comes from the Evenki language meaning "dark waters."
More than 100 years have passed since the Tunguska Meteorite Event and the mystery of its occurrence remains unsolved, but scientists have not given up on solving the riddle. This July, an international research group from Italy and the United States ventured into deepest Siberia to investigate the most likely explanations of the mysterious event, and RIA Novosti correspondent David Burghardt joined them.

On June 30, 1908, Eastern Siberia was hit by an explosion equal to 2,000 times the nuclear bomb that destroyed the Japanese city of Hiroshima in 1945, destroying 2,200 square kilometers of taiga and flattening tens of millions of trees. If this impact had occurred four hours later, the city of St. Petersburg and other nearby villages would have been wiped off the face of the earth.

Comment: For an in-depth review, read Tunguska, Psychopathy and the Sixth Extinction.


Telescope

Spitzer Images Out-Of-This-World Galaxy

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In the Spitzer image, infrared light with shorter wavelengths is blue, while longer- wavelength light is red. The galaxy's red spiral arms and the swirling spokes seen between the arms show dust heated by newborn stars. Older populations of stars scattered through the galaxy are blue. The fuzzy blue dot to the left, which appears to fit snuggly between the arms, is a companion galaxy.
NASA's Spitzer Space Telescope has imaged a wild creature of the dark - a coiled galaxy with an eye-like object at its center. The galaxy, called NGC 1097, is located 50 million light-years away. It is spiral-shaped like our Milky Way, with long, spindly arms of stars.

The "eye" at the center of the galaxy is actually a monstrous black hole surrounded by a ring of stars. In this color-coded infrared view from Spitzer, the area around the invisible black hole is blue and the ring of stars, white.

The black hole is huge, about 100 million times the mass of our sun, and is feeding off gas and dust along with the occasional unlucky star. Our Milky Way's central black hole is tame by comparison, with a mass of a few million suns.

"The fate of this black hole and others like it is an active area of research," said George Helou, deputy director of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena. "Some theories hold that the black hole might quiet down and eventually enter a more dormant state like our Milky Way black hole."

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Finding King Herod's Tomb

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© Duby Tal / Albatross / IsraelImages
Herod built an elaborate palace fortress on the 300-foot mountain, Herodium, to commemorate his victory in a crucial battle.
Shielding my eyes from the glare of the morning sun, I look toward the horizon and the small mountain that is my destination: Herodium, site of the fortified palace of King Herod the Great. I'm about seven miles south of Jerusalem, not far from the birthplace of the biblical prophet Amos, who declared: "Let justice stream forth like water." Herod's reign over Judea from 37 to 4 B.C. is not remembered for justice but for its indiscriminate cruelty. His most notorious act was the murder of all male infants in Bethlehem to prevent the fulfillment of a prophecy heralding the birth of the Messiah. There is no record of the decree other than the Gospel of Matthew, and biblical scholars debate whether it actually took place, but the story is in keeping with a man who arranged the murders of, among others, three of his own sons and a beloved wife.

Meteor

Stephen Hawking: Space debris represents biggest natural threat to humanity

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© Space Telescope Science Institute
Something wicked this way comes
Stephen Hawking believes that one of the major factors in the possible scarcity of intelligent life in our galaxy is the high probability of an asteroid or comet colliding with inhabited planets. "We have observed," Hawking points out in Life in the Universe, "the collision of a comet, Schumacher-Levi, with Jupiter (below), which produced a series of enormous fireballs, plumes many thousands of kilometers high, hot "bubbles" of gas in the atmosphere, and large dark "scars" on the atmosphere which had lifetimes on the order of weeks."

It is thought the collision of a rather smaller body with the Earth, about 70 million years ago, was responsible for the extinction of the dinosaurs. A few small early mammals survived, but anything as large as a human, would have almost certainly been wiped out.

Comment:



Meteor

New Image of Jupiter Impact in Infrared

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© Gemini Observatory / AURA
After getting whacked unexpectedly by a small comet or asteroid, Jupiter is sporting a "bruise," which has been big news this week. In visible wavelengths, the impact site appears as a black spot. But in a new image taken in near infrared by the Gemini North telescope on Mauna Kea, Hawai'i, the spot shows up in spectacular glowing yellow.

"We utilized the powerful mid-infrared capabilities of the Gemini telescope to record the impact's effect on Jupiter's upper atmosphere," said Imke de Pater from the University of California, Berkeley. "At these wavelengths we receive thermal radiation (heat) from the planet's upper atmosphere. The impact site is clearly much warmer than its surroundings, as shown by our image taken at an infrared wavelength of 18 microns."

As Universe Today reported earlier, this new spot on Jupiter was first seen by Australian amateur astronomer Anthony Wesley on July 19th. This set off a flurry of activity as the large ground based observatories have imaged Jupiter in attempt to learn more about the impact and the object that struck Jupiter. Astronomers now say the object was likely a small comet or asteroid, just a few hundreds of meters in diameter. Such small bodies are nearly impossible to detect near or beyond Jupiter unless they reveal cometary activity, or, as in this case, make their presence known by impacting a giant planet.

Comment: Have you read Stephen Hawking: Space debris represents biggest natural threat to humanity?


Info

Genes responsible for brain cancer found

© Unknown
Scientists have discovered a network of genetic changes involved in the development and progression of glioblastoma, a severe form of brain cancer.

While previous studies had reported hundreds of gene mutations accounting for brain cancers, a new study finds seven key genes acting as the 'Achilles heel' of these tumors.

According to the study published in the Journal of the American Medical Association, the development and progression of malignant glioblastomas is related to the interaction between seven genes.

Chalkboard

Strange! Humans Glow in Visible Light

The human body literally glows, emitting a visible light in extremely small quantities at levels that rise and fall with the day, scientists now reveal.

Past research has shown that the body emits visible light, 1,000 times less intense than the levels to which our naked eyes are sensitive. In fact, virtually all living creatures emit very weak light, which is thought to be a byproduct of biochemical reactions involving free radicals.

(This visible light differs from the infrared radiation - an invisible form of light - that comes from body heat.)

To learn more about this faint visible light, scientists in Japan employed extraordinarily sensitive cameras capable of detecting single photons. Five healthy male volunteers in their 20s were placed bare-chested in front of the cameras in complete darkness in light-tight rooms for 20 minutes every three hours from 10 a.m. to 10 p.m. for three days.

Roses

Stop and smell the flowers -- the scent really can soothe stress

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© Wikimedia Commons
Scientists are reporting the first scientific evidence that certain fragrances can alter gene activity and blood chemistry in ways that reduce stress levels.
Feeling stressed? Then try savoring the scent of lemon, mango, lavender, or other fragrant plants. Scientists in Japan are reporting the first scientific evidence that inhaling certain fragrances alter gene activity and blood chemistry in ways that can reduce stress levels. Their study appears in ACS' Journal of Agricultural and Food Chemistry, a bi-weekly publication.

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Australia discovered by the 'Southern Route'

Genetic research indicates that Australian Aborigines initially arrived via south Asia. Researchers writing in the open access journal BMC Evolutionary Biology have found telltale mutations in modern-day Indian populations that are exclusively shared by Aborigines.

Dr Raghavendra Rao worked with a team of researchers from the Anthropological Survey of India to sequence 966 complete mitochondrial DNA genomes from Indian 'relic populations'. He said, "Mitochondrial DNA is inherited only from the mother and so allows us to accurately trace ancestry. We found certain mutations in the DNA sequences of the Indian tribes we sampled that are specific to Australian Aborigines. This shared ancestry suggests that the Aborigine population migrated to Australia via the so-called 'Southern Route'".

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Ancient Humans Left Evidence from the Party that Ended 4,000 Years Ago

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© Unknown
Gourd and squash artifacts were recovered from the sunken pit and platform in the Fox Temple at the Buena Vista site in central Peru.
Columbia, Mo. - The party was over more than 4,000 years ago, but the remnants still remain in the gourds and squashes that served as dishware. For the first time, University of Missouri researchers have studied the residues from gourds and squash artifacts that date back to 2200 B.C. and recovered starch grains from manioc, potato, chili pepper, arrowroot and algarrobo. The starches provide clues about the foods consumed at feasts and document the earliest evidence of the consumption of algarrobo and arrowroot in Peru.

"Archaeological starch grain research allows us to gain a better understanding of how ancient humans used plants, the types of food they ate, and how that food was prepared," said Neil Duncan, doctoral student of anthropology in the MU College of Arts and Science and lead author of the study that was published in the Proceedings of the National Academy of Science (PNAS) this week. "This is the first study to analyze residue from bottle gourd or squash artifacts. Squash and bottle gourds had a variety of uses 4,000 years ago, including being used as dishes, net floats and symbolic containers. Residue analysis can help determine the specific use."