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By (Tag bylines with individual items.), New York Times
A Japanese spacecraft reaches its target, but the hit is still on the road
Here is the mission of the Japanese spacecraft Hayabusa2: flying towards a carbon-rich asteroid between the orbits of Earth and Mars, study it for a year and a half and then bring back some pieces for further study on Earth.
The Hayabusa2 was launched in 2014. On June 27, he reached his target, and is now a few miles above Ryugu, an asteroid about half a mile wide. Japanese astronomers who study it say that it has the shape of a peak or even a pearl of abacus
Ryugu, as dark as coal, is a asteroid carbon, which means that it is full of carbon molecules known as amino acids. building blocks of proteins. Such molecules are not always badociated with biology and may form from chemical reactions in deep space, but asteroids may have sown the Earth with the organic matter that led to life
within 3.1 miles of Ryugu's surface to measure the gravitational field around the asteroid. In September or October, Hayabusa2 must perform its first "touch operation" on the asteroid.
At this point, he may deploy one or more of the three small rovers that he carries. He can also deploy a lander of European construction then
Then he will take a break in November and December, because the sun will be directly between Ryugu and the Earth, blocking communications.
After that, the spacecraft will make a couple more landings, as well as drop a copper projectile into the asteroid to create a crater. This will allow the spacecraft to collect material below the surface.
By the end of 2019, Hayabusa2 must leave the asteroid and return to Earth. In 1965, he will drop a capsule with asteroid samples.
– Kenneth Chang
Bumblebees thrive in the city but fight on the farm
Bumblebees in London may be better off than their parents in the English countryside, suggests a recently published study in Proceedings of the Royal Society B.
"We do not say that urban areas are the solution to the decline of drones or that urban areas are the ideal habitat," said Ash Samuelson, a graduate student. at the Royal Holloway University of London in Britain and lead author of the study. "But given the choice of two unnatural situations, they are able to exploit this urban environment, which is very different from their evolution."
Bumblebees are important pollinators for flowers and crops that benefit from their vibrant pollination. But pesticides, diseases and habitat loss are wiping out all types of bees worldwide. People have noticed that more drones are buzzing around cities. Samuelson wanted to know if the bees were just going to the cities when the agricultural fields ran out of food or if they survived better there and had more babies.
Some biologists have suggested that cities could offer shelter to bees. there was reason to think that living in an urban setting was not great for bees. Some flowers in cities may be prettier for people than they are rewarding or attractive to drones. Competition with other pollinators can be difficult. The crowds are dangerous: the parasites are found more heavily on bumblebees in urban areas.
The Samuelson team collected more than 100 wild queens and brought them back to the lab to build colonies. They then transplanted colonies to 38 different sites
Compared with towns and villages, settlements in agricultural fields produced fewer breeding progeny and fewer workers, and their queens died earlier. Their settlements, which broke down faster than settlements in towns and villages, also had fewer nutrient stores.
But even more remarkable, the suburban settlements were not better off than the urban settlements
. The new research offers relief and warning: It is positive that bumblebees can exploit the resources of the city, but the agricultural fields of the future should be more favorable to bees. This may require additional landscaping for farms; research has shown that planting wildflowers or flowering hedges near crop fields can help restore pollinator habitat and foraging opportunities
– Joanna Klein
true murderer of Pompeii. Internet: "The unlucky man of Pompeii". But the story that has spread about his disappearance has been greatly exaggerated, a new discovery suggests.
In May, archaeologists discovered the remains of a man crushed by a flying rock. fleeing the eruption of Vesuvius in 79 AD. Only his skeletal legs and torso protruded below the 600-pound block.
At that time, the team reported that a volcanic cloud had launched a stone door jamb towards the man.
But other excavations have uncovered the intact skull of the man with his mouth wide open (and full of teeth), suggesting that he was not crushed by a volcanic projectile. The skull and upper torso and the arms of the man were found about 3 feet almost directly below the rest of the body and the gigantic stone. The team said that they knew that the bones belonged to the same person because of their proximity to each other and because the two halves correspond.
"The death of the victim is not due to the blockage of the skull" Osanna, director of the archaeological site of Pompeii. "Our new hypothesis is that he died from asphyxiation of the pyroclastic flow."
The team had already determined that the man, whom we thought about 35 years old, had a physical defect that caused him to limp. It is possible that the handicap has slowed it down, making it more vulnerable to harmful gases and ashes. He was one of about 2,000 known victims of the eruption.
The team thinks that the upper torso of the man's was separated from the lower half of 1748 and 1815 when Naples was under the control of the Bourbon dynasty. Meanwhile, archaeologists often dug tunnels in the ashes. Osanna and her team believe that the excavators were able to dig a tunnel under the skeleton that eventually collapsed, causing the skull and upper torso to fall.
The team does not know exactly when the block fell on the body. One hypothesis is that the man was in or near a building during the eruption when he suffocated and died. The walls – and the large block of stone – may have collapsed at the same time or later and fell on the dead body.
– Nicholas St. Flower
As an alien of space, Oumuamua is a kind of Dud
He came from the space, zooming through the solar system at 50 miles per second last October: a reddish cigar-shaped rock named Oumuamua.
It was something interstellar, but what exactly? Some astronomers have turned radio telescopes in case it would act from an alien space ship, but it was silent.
Astronomers had long considered that interstellar debris could invade the solar system from time to time, in the form of frozen pieces. rocky discs forming distant planets, that is, interstellar comets. And they arrived in strange orbits like Oumuamua
But Oumuamua never illuminated as a comet during its pbadage beyond the sun and our kingdom, and astronomers therefore concluded that was an extraterrestrial asteroid
however, the same team that discovered Oumuamua concluded that it was a comet after all.
The key to this conclusion comes from an badysis of the trajectory of Oumuamua as measured by a variety of telescopes by Dr. Marco Micheli of the European Space Agency. SSA-NEO Coordination Center, Frascati, Italy. Micheli found that the gravity of the sun and planets was not the only force acting on the little wanderer. Something else was pushing the object away from the sun.
Such "non-perennial" forces caused by degbading gases and dust are characteristic of comets.
Unlike asteroids, which are mostly rocks, comets are sometimes called "snowballs". , "Conglomerates of various kinds of ice with rock and dust.When they get closer to the sun, these ice creams vaporize, carrying gas and dust in a cloud around the nucleus of the comet.The gas is spreading in small geysers or jets, which act as thrusters of a spaceship.
As Micheli explained in an e-mail, these jets are usually on the sunny side of the comet. as a typical comet gets closer to the sun, the jets cause a braking effect, so that the comet falls a little slower than if gravity lured it to the sun.
Astronomers only have Oumuamua observed on his outer journey, when he was moving away from the sun, however, as Micheli said, "the object moves away from the sun and slows down, and l '& Michel Michel Michel Michel Michel Michel Michel,,,,,,. Degbading effect acts in the opposite direction, and accelerates it a bit. "
This is ex Actually what Oumuamua seems to have done, according to Micheli.
– Dennis Overbye
Using DNA Mapping to Find Salvation for Bigleaf Maples
Forests are disappearing. The maps show shrinking woodland all over the world. Even the coveted trees for their timber protected from logging are slaughtered.
Worried about this deforestation, environmental advocates are leading a project to create a DNA database of large-leaf maple populations on the west coast. The ultimate goal is to use DNA mapping to combat the successful black markets of timber in tropical countries plagued by illegal logging. "19659004" We collect leaf tissue from maple trees and take samples along the entire length of the species. from Southern California to British Columbia, "said Meaghan Parker-Forney, Scientific Officer of the World Resources Institute, a non-profit organization that promotes environmental sustainability and works on the monthly initiative [19659020]. The Norwegian government, which jointly finances the effort with the US Forest Service's international program. Norway hopes to see if such a database is feasible in places like Indonesia and Peru, where illegal logging is ubiquitous.
Using volunteers from Adventure Scientists, a non-profit organization specializing in external data collection, the World Resources Institute of Bigleaf Maple, and the unique characteristics of each population.
Advocates of the environment hope that DNA databases could be used for legal reasons. Several people in the United States have been found guilty of illegal exploitation using DNA evidence. Genetic markers can indicate if a tree has been exploited from a protected place.
"If anyone came to us and told us that his wood came from the state of Washington, we could tell if the wood was declarant came from a legal place, or we could say it's actually not where it comes from, "said Parker-Forney.
The DNA collection is quite simple.Volunteers are trained online by adventure scientists and use an app to record the field information.
Nineteen volunteers collected DNA samples for the tree project. Currently, only one volunteer is collecting large-leaf maple samples near the Port Mellon Expressway in Gibsons, BC Seventy-four other volunteers are ready for deployment. to be finished in December
– Sandra E. Garcia
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