Group items tagged

US embassy air quality Twitter feed gained a major following in Beijing, and later in Shanghai when it was introduced at the US consulate there

Beijing announced earlier this year it would change the way it measured air quality to include the smaller particles experts say make up much of the pollution in Chinese cities, after a vocal campaign

publishing of China's air quality are related to the public interests and as such are powers reserved for the government

vice minister of environment protection

did not name the US, but called on embassies to abide by China's laws

China's air quality is among the worst in the world

According to the latest Environmental Performance Index compiled by Yale University, China ranked 128th out of 132 countries for air quality.

Most Chinese cities base their air-quality information on particles of 10 micrometres or larger

China seeks to control the sources of particulates, such as coal burning and auto emissions

Find Orion, Leo or Crux by going outside more than an hour after sunset (about 8-10pm local time).

Match your nighttime sky to one of the provided magnitude charts.

Report your observation.

Compare your observation to thousands around the world

You can also use the new web application data submission process

People in 115 countries have contributed over 75,000 measurements during the past six years

weighs about 100 pounds,

In the video, the robot turns some circles and navigates on the lake's surface.

can carry 150 pounds' worth of sensing equipment

can be controlled from anywhere around the world using an Internet connection

working on making the craft more autonomous

wants to create data-gathering robots that have a sense of curiosity

investigate certain places, learn from what they find and use that information to decide what to explore next. 

an improved version

could help officials survey the cleanup of dangerously polluted water in munitions dumps and mines

also could help ocean scientists gather data about currents and pollution.

For a mission to Titan

NASA is interested in rovers that can land on liquid rather than on solid ground

imagery shows that glaciers in the region were melting even faster in the 1930s than they are today

A brief cooling period starting in the mid-20th century allowed new ice to form, and then the melting began to accelerate again in the 2000s.

we now have a detailed historical analogue for more recent glacier loss

confirmed that glaciers are very sensitive indicators of climate."

cleaning up in the basement and had found some old glass plates with glaciers on them

The reason the plates were forgotten was that they were recorded for mapping, and once the map was produced they didn't have much value."

They contained aerial photographs of land, sea and glaciers in the southeast region of the country, along with travel photos of Rasmussen's team.

researchers digitized all the old images and used software to look for differences in the shape of the southeast Greenland coastline where the ice meets the Atlantic Ocean

calculated the distance the ice front moved in each time period.

Over the 80 years, two events stand out: glacial retreats from 1933-1934 and 2000-2010

1930s, fewer glaciers were melting than are today, and most of those that were melting were land-terminating glaciers, meaning that they did not contact the sea.

were melting retreated an average of 20 meters per year - the fastest retreating at 374 meters per year

Fifty-five percent of the glaciers in the study had similar or higher retreat rates during the 1930s than they do today.

more glaciers in southeast Greenland are retreating today, and the average ice loss is 50 meters per year. That's because a few glaciers with very fast melting rates - including one retreating at 887 meters per year - boost the overall average.

From 1943-1972, southeast Greenland cooled - probably due to sulfur pollution, which reflects sunlight away from the earth.

Sulfur dioxide is a poisonous gas produced by volcanoes and industrial processes. It has been tied to serious health problems and death, and is also the main ingredient in acid rain.

deadly pollution caused the climate to cool, but rather that the brief cooling allowed researchers to see how Greenland ice responded to the changing climate.

glaciers responded to the cooling more rapidly than researchers had seen in earlier studies

Sixty percent of the glaciers advanced during that time, while 12 percent were stationary

now that the warming has resumed, the glacial retreat is dominated by marine-terminating outlet glaciers, the melting of which contributes to sea level rise.

we see that the mid-century cooling stabilized the glaciers," Box said. "That suggests that if we want to stabilize today's accelerating ice loss, we need to see a little cooling of our own."

April 22

plans to land four people on the Red Planet in 2023

permanent human colony on the Red Planet, with new crews arriving every two years thereafter

Human explorers

will doubtless contaminate whatever site is chosen for the settlement

so the organization will try to pick a place unlikely to host indigenous life

localize the pollution

Mars One is working with experts to minimize the risks its colonization effort may pose to potential Red Planet lifeforms

While Mars One hasn't picked a precise location for its settlement yet, the organization is targeting a swath of the Red Planet between 40 and 45 degrees north latitude

Mars One astronauts will not necessarily be scientists

Anyone over the age of 18 is eligible to apply, with the selection committee prizing traits such as intelligence, resourcefulness, determination and psychological stability over academic background

Science is

not the main focus of what we are doing

Crewmembers will take some scientific gear with them

but Mars One officials won't dictate what the experiments should be.

There will of course be a budget for equipment that they want to take for scientific research

This data can be used to map the distribution and changes in sky brightness, and will eventually allow scientists to investigate correlations with health, biodiversity, energy waste and other factors

The app works by interactively asking users to say whether individual stars are visible. By determining what the faintest visible star is, the researchers learn how many stars are visible at that location, and by extension how bright the sky is

With this app, people from around the world can collect data on skyglow without needing expensive equipment

some of the testers found that without intending too they learned the names of several stars and constellations

is based on the widely used Google Sky Map application

development of the app was sponsored by the German Federal Ministry of Research and Education,

satellites that observe Earth at night measure the light that is radiating into the sky, not the brightness that is experienced by people and other organisms on the ground

results “suggest that lightning has its own unique effect on headache

how exactly lightning might trigger headaches

there are a number of possible explanations

Electromagnetic waves emitted from lightning could trigger headaches

lightning produces increases in air pollutants like ozone, and can cause release of fungal spores that might lead to migraine

while the study sheds light on the apparent link between lightning and headaches, “the exact mechanisms through which lightning and/or its associated meteorologic factors trigger headache are unknown

can be used to corroborate age estimates inferred by other means

In the past, analyses of globular clusters and the Hubble constant

yielded vastly different ages for the Universe, and were offset by billions of years

based on the microwave background and Hubble constant, but it must have formed soon after the big bang

Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 ± 0.06 billion years

Metal-poor stars can be used to constrain the age of the Universe because metal-content is typically a proxy for age

Heavier metals are generally formed in supernova explosions, which pollute the surrounding interstellar medium.

Stars subsequently born from that medium are more enriched with metals than their predecessors

each successive generation becoming increasingly enriched

HD 140283 exhibits less than 1% the iron content of the Sun, which provides an indication of its sizable age.

had been used previously to constrain the age of the Universe, but uncertainties tied to its estimated distance (at that time) made the age determination somewhat imprecise

obtain a new and improved distance for HD 140283 using the Hubble Space Telescope (HST), namely via the trigonometric parallax approach

distance uncertainty for HD 140283 was significantly reduced by comparison to existing estimates, thus resulting in a more precise age estimate for the star

The reliability of the age determined is likewise contingent on accurately determining the sample’s metal content

analyses of globular clusters and the Hubble constant yielded vastly different ages for the Universe

discrepant ages stemmed partly from uncertainties in the cosmic distance scale

determination of the Hubble constant relied on establishing (accurate) distances to galaxies

One of the key objectives envisioned for HST was to reduce uncertainties associated with the Hubble constant to <10%, thus providing an improved estimate for the age of the Universe

the mean implying an age near ~14 billion years

Determining a reliable age for stars in globular clusters is likewise contingent on the availability of a reliable distance

the study reaffirms that there are old stars roaming the solar neighborhood which can be used to constrain the age of the Universe