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moon is older than we thought

 

This makes the Earth’s satellite up to 140 million years older than previously thought.

The Moon is at least 4.51 billion years old — up to 140 million years older than previously thought, according to a new study of minerals called zircons brought back from the lunar body to the Earth by the Apollo 14 mission in 1971.

The Moon’s age has been a hotly debated topic, even though scientists have tried to settle the question over many years and using a wide range of scientific techniques.

“We have finally pinned down a minimum age for the Moon; it is time we knew its age and now we do,” said Melanie Barboni, research geochemist at University of California, Los Angeles (UCLA) in the United States.

Head-on collision created it

The Moon was formed by a violent, head-on collision between the early Earth and a “planetary embryo” called Theia.

The new study would mean that Moon formed “only” about 60 million years after the birth of the solar system, providing critical information for astronomers and planetary scientists who seek to understand the early evolution of the Earth and our solar system, researchers said.

That has been a difficult task, Ms. Barboni said, because “whatever was there before the giant impact has been erased.”

While scientists cannot know what occurred before the collision with Theia, these findings are important because they will help scientists continue to piece together major events that followed it.

How it was arrived at

It is usually difficult to determine the age of Moon rocks because most of them contain a patchwork of fragments of multiple other rocks. However, Ms. Barboni was able to analyse eight zircons in pristine condition.

She examined how the uranium they contained had decayed to lead and how the lutetium they contained had decayed to an element called hafnium.

The researchers analysed those elements together to determine the Moon’s age.

Zircons are the best clocks

“Zircons are nature’s best clocks. They are the best mineral in preserving geological history and revealing where they originated,” said Kevin McKeegan, a UCLA professor of geochemistry and cosmo-chemistry.

The Earth’s collision with Theia created a liquefied Moon, which then solidified. Scientists believe most of the Moon’s surface was covered with magma right after its formation.

The uranium-lead measurements reveal when the zircons first appeared in the Moon’s initial magma ocean, which later cooled down and formed the Moon’s mantle and crust; the lutetium-hafnium measurements reveal when its magma formed, which happened earlier.

Previous studies concluded the Moon’s age based on Moon rocks that had been contaminated by multiple collisions.

Professor McKeegan said those rocks indicated the date of some other events, “but not the age of the Moon.”

dedicated by

Kavignar Thanigai.

 

Boy or girl? Mother’s BP may predict sex of baby

thanks: Times of India

Image result for boy or girl

 

Toronto: The sex of a baby may be predicted by the mother’s blood pressure, according to a new study which found that women with lower BP before pregnancy are more likely to give birth to a girl.

Researchers led by Dr Ravi Retnakaran, endocrinologist at Mount Sinai Hospital in Canada found that while higher blood pressure was an indication that a boy was more likely to be conceived, women with lower blood pressure tended to give birth to a girl.

This “suggests that a woman’s blood pressure before pregnancy is a previously unrecognised factor that is associated with her likelihood of delivering a boy or a girl,” said Retnakaran.

“This novel insight may hold implications for both reproductive planning and our understanding of the fundamental mechanisms underlying the sex ratio in humans,” he said.

The possibility of predicting the sex of the baby in early pregnancy has long been a topic of public fascination, spawning numerous theories of maternal characteristics associated with the presence of a male or female foetus.

These observations raise the possibility that there may be underlying differences that relate to a woman’s likelihood of sex-specific fetal loss and hence her likelihood of delivering a boy or girl. However, little is known about such factors in humans.

Researchers established a unique pre-conception cohort consisting of young women who were planning to have a pregnancy in the near future and used the model to evaluate the relationship between maternal pre-pregnancy health and the sex of the baby.

Participants underwent baseline medical assessment at recruitment and then, whenever they subsequently became pregnant, were followed across the pregnancy up to delivery through their clinical care.

Beginning in February 2009, researchers recruited 3375 women in Liuyang, China. Of these, 1,692 women were assessed for blood pressure, cholesterol, triglycerides, and glucose.

After the exclusion of 281 women who were potentially pregnant at their baseline assessment based on back-dating of the length of gestation at delivery, the study population for the analysis consisted of 1,411 women who were assessed at median 26.3 weeks before pregnancy.

dedicated by: Kavignar Thanigai.

APPENDIX IS USEFUL – NEW STUDY REVEALS….KAVIGNAR THANIGAI.

THANKS PTI, times of india

WASHINGTON: The human appendix, which is thought to be of little use to the body, may actually serve as a reservoir for beneficial gut bacteria, a new study has found. The appendix, a narrow pouch that projects off the caecum in the digestive system, has a notorious reputation for its tendency to become inflamed (appendicitis), often needing surgical removal.

Researchers from the Midwestern University Arizona College of Osteopathic Medicine in the US gathered data on the presence or absence of the appendix and other gastrointestinal and environmental traits for 533 mammal species.

Image result for appendix meaning

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It should be very well understood that God has not created any organ in the human body which is not useful.Natanam Iyer

They mapped the data onto a phylogeny (genetic tree) to track how the appendix has evolved through evolution, and to try to determine why some species have an appendix while others do not. They discovered that the appendix has evolved independently in several mammal lineages, and almost never disappears from a lineage once it has appeared. This suggests that the appendix likely serves an adaptive purpose.

They found out that species with an appendix have higher average concentrations of lymphoid (immune) tissue in the caecum. Lymphatic tissue can stimulate growth of some types of beneficial gut bacteria.

 

 

Moon may have formed from collision of tiny moonlets, shows new study

thanks: business standard 11th Jan.2017 and Nature Gioscience

dedicated by: kavignar Thanigai.

 

Full Moon

 

Small ‘moonlets’ may have collided to form the as we see it today, according to a new study which contradicts the prevalent theory that our natural satellite resulted from a giant impact between a small Mars-like planet and the ancient Earth.

 

The study also claims that the we see now is not Earth’s first moon, but rather the last in a series of moons that orbited our planet.

 

The newly proposed theory by researchers at the and Weizmann Institute of in Israel counter to the commonly held “giant impact” paradigm that the is a single object that was formed following a single giant collision between a small Mars-like planet and the Earth.

 

“Our model suggests that the ancient once hosted a series of moons, each one formed from a different collision with the proto-Earth,” said Hagai Perets from the Technion.

 

“It is likely that such moonlets were later ejected, or collided with or with each other to form bigger moons,” said Perets.

 

To check the conditions for the formation of such mini-moons or moonlets the researchers ran 800 simulations of impacts with Earth.

 

The new model is consistent with science’s current understanding of the formation of Earth.

 

In its last stages of the growth, experienced many giant impacts with other bodies.

 

Each of these impacts contributed more material to the proto-Earth, until it reached its current size.

 

“We believe had many previous moons, a previously formed could therefore already exist when another moon-forming giant impact occurs,” said Perets.

 

The tidal forces from could cause moons to slowly migrate outwards – the current is slowly doing that at a pace of about one centimetre a year.

 

A pre-existing would slowly move out by the time another forms.

 

However, their mutual gravitational attraction would eventually cause the moons to affect each other and change their orbits.

 

“It is likely that small moons formed through the process could cross orbits, collide and merge,” said lead author Raluca Rufo from Weizmann.

 

“A long series of such moon-collisions could gradually build-up a bigger – the we see today,” said Rufo.

Rare Comet Will Be Visible From Earth For First Time: NASA

by: NDTV

Dedicated by: KAVIGNAR THANIGAI.

 

Rare Comet Will Be Visible From Earth For First Time: NASA

 

WASHINGTON:  A rare comet discovered by NASA scientists will be visible using just binoculars to skywatchers on Earth this week for the first time, before the object heads back into outer reaches of the solar system for an orbit lasting thousands of years.

The comet, C/2016 U1 NEOWISE, “has a good chance of becoming visible through a good pair of binoculars, although we can’t be sure because a comet’s brightness is notoriously unpredictable,” said Paul Chodas, manager of NASA’s Centre for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in the US.

As seen from the northern hemisphere during the first week of 2017, comet C/2016 U1 NEOWISE will be in the southeastern sky shortly before dawn.

It is moving farther south each day and it will reach its closest point to the Sun, inside the orbit of Mercury, on January 14, before heading back out to the outer reaches of the solar system for an orbit lasting thousands of years. While it will be visible to skywatchers at Earth, it is not considered a threat to our planet either.

NASA’s NEOWISE mission has recently discovered some celestial objects travelling through our neighbourhood, including one on the blurry line between asteroid and comet. An object called 2016 WF9 was detected by the NEOWISE project on November 27 last year.

It is in an orbit that takes it on a scenic tour of our solar system. At its farthest distance from the Sun, it approaches Jupiter’s orbit.

Over the course of 4.9 Earth-years, it travels inward, passing under the main asteroid belt and the orbit of Mars until it swings just inside Earth’s own orbit. After that, it heads back toward the outer solar system.

Objects in these types of orbits have multiple possible origins; it might once have been a comet, or it could have strayed from a population of dark objects in the main asteroid belt.

2016 WF9 will approach Earth’s orbit on February 25 this year. At a distance of nearly 51 million kilometres from Earth, this pass will not bring it particularly close.

The trajectory of 2016 WF9 is well understood, and the object is not a threat to Earth for the foreseeable future. A different object, discovered by NEOWISE a month earlier, is more clearly a comet, releasing dust as it nears the Sun.

NEOWISE is the asteroid-and-comet-hunting portion of the Wide-Field Infrared Survey Explorer (WISE) mission.

2016 WF9 is relatively large: roughly 0.5 to 1 kilometre across. It is also rather dark, reflecting only a few percent of the light that falls on its surface.

This body resembles a comet in its reflectivity and orbit, but appears to lack the characteristic dust and gas cloud that defines a comet.

“2016 WF9 could have cometary origins,” said Deputy Principal Investigator James Bauer at JPL.

“This object illustrates that the boundary between asteroids and comets is a blurry one; perhaps over time this object has lost the majority of the volatiles that linger on or just under its surface,” said Bauer.

Astroboffins glimpse sighting of ultra-rare circular galaxy- kavignar Thanigai.

A rarer-than-rare galaxy 359 million light years away from Earth has been spotted by physicists.

Hoags Object

Designated PGC 1000714 [paywalled], the galaxy is a ring-shape system orbiting a cooler centre without any connection between the two – a formation referred to as Hoag’s Object.

Just 0.1 per cent of all observed galaxies are Hoag-type systems; the majority follow the hub and spiral-arm standard like our own Milky Way or the neighbouring Andromeda. PGC 1000714 is rarer still, though.

Hoag’s Object, discovered 67 years ago by astronomer Arthur Allan Hoag and named after him, features a single ring of blue stars orbiting a yellow core.

PGC 1000714 features a second ring of blue stars with both rings orbiting a red core.

Nobody has yet managed to adequately explain the formation of the original Hoag’s Object – never mind the related-yet-different PGC 1000714, which was spotted by scientists at the University of Minnesota Duluth and the North Carolina Museum of Natural Sciences.

Burcin Mutlu-Pakdil, lead author of a paper on this work, said in a statement: “The different colors of the inner and outer ring suggest that this galaxy has experienced two different formation periods.”

Galaxy rings are regions where stars have formed from colliding gas – hence the reason for the different colours.

“From these initial single snapshots in time, it’s impossible to know how the rings of this particular galaxy were formed,” Mutlu-Pakdil said.

One possibility is that the outer ring may be the result of this galaxy incorporating portions of a once-nearby gas-rich dwarf galaxy.

The galaxy was spotted and analysed using multi-waveband images from observations in the southern hemisphere, using a large-diameter telescope in the Chilean mountains. These images were used to determine the ages of the two main features of the galaxy, the outer ring and the central body.

The outer ring is 0.13 billion years old and the red core 5.5 billion years. Higher-resolution images are needed to infer the age of the inner ring.

The original Hoag’s Object, spotted in 1950, shows a ring of blue stars spanning 100,000 light years and lying 600 million light years away in Serpens Constellation. ®

thanks : the register, Science

dedicated by: Kavignar Thanigai.

Scientists have discovered a new organ in the human digestive system.:Kavignar Thanigai.

Did you know human beings have a brand new organ? (It was hiding in plain sight)

Scientists have discovered a new organ in the human digestive system.

mesentery-new-organ_759_yt-kenhub

 

Scientists in Ireland have classified a brand-new organ inside human body, one that has been hiding in plain sight in our digestive system, proving the anatomic description laid down over 100 years of anatomy as incorrect. Researchers hope that the reclassification will aid better understanding and treatment of abdominal and digestive diseases.

The mesentery, which connects the intestine to the abdomen, had for hundreds of years been considered a fragmented structure made up of multiple separate parts. However, new research by J Calvin Coffey, Professor of Surgery at University of Limerick in Ireland, describes the mesentery as one, continuous structure.

In a review published in the journal The Lancet Gastroenterology and Hepatology, Coffey outlined the evidence for categorising the mesentery as an organ. “In the paper, which has been peer reviewed and assessed, we are now saying we have an organ in the body which has not been acknowledged as such to date,” Coffey said. Better understanding and further scientific study of the mesentery could lead to less invasive surgeries, fewer complications, faster patient recovery and lower overall costs.

“When we approach it like every other organ, we can categorise abdominal disease in terms of this organ,” Coffey said.

Also see

According to Coffey, mesenteric science is its own specific field of medical study in the same way as gastroenterology, neurology and coloproctology. “This is relevant universally as it affects all of us. Up to now there was no such field as mesenteric science. Now we have established anatomy and the structure. The next step is the function.

“If you understand the function you can identify abnormal function, and then you have disease. Put them all together and you have the field of mesenteric science. The basis for a whole new area of science,” he said. “During the initial research, we noticed in particular that the mesentery, which connects the gut to the body, was one continuous organ. Up to that it was regarded as fragmented, present here, absent elsewhere and a very complex structure.

“The anatomic description that had been laid down over 100 years of anatomy was incorrect. This organ is far from fragmented and complex. It is simply one continuous structure,” Coffey said.

 

According to Coffey, mesenteric science is its own specific field of medical study in the same way as gastroenterology, neurology and coloproctology. “This is relevant universally as it affects all of us. Up to now there was no such field as mesenteric science. Now we have established anatomy and the structure. The next step is the function.

“If you understand the function you can identify abnormal function, and then you have disease. Put them all together and you have the field of mesenteric science. The basis for a whole new area of science,” he said. “During the initial research, we noticed in particular that the mesentery, which connects the gut to the body, was one continuous organ. Up to that it was regarded as fragmented, present here, absent elsewhere and a very complex structure.

“The anatomic description that had been laid down over 100 years of anatomy was incorrect. This organ is far from fragmented and complex. It is simply one continuous structure,” Coffey said.

 

dedicated by|Kavignar Thanigai

thanks to Indian express.Jan.4th

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