Tag Archives: atmosphere

What Do Sunsets Look Like From Other Planets?

A University of Exeter astrophysicist has shown what sunsets look like on planets outside our solar system.

He has worked out the colour of sunsets on two planets: HD 209458 b and HD 189733 b, known as ‘extrasolar planets’ because they are outside our solar system.

Extrasolar planets orbit stars, in a similar way to the Earth orbiting the Sun. Professor Frédéric Pont of the University of Exeter has used the extrasolar planets’ ‘transmission spectrum’, taken by the Hubble Space Telescope, to work out the colour of the ‘sunsets’ created by these stars.

Writing on the website ExoClimes.com, where he has posted the two sunset images he has produced, Professor Pont said: “Unlike its sister planet HD ’189, the planet HD ’209 (‘Osiris’) has a sunset that looks truly alien. The star is white outside the atmosphere, since its temperature is close to that of the Sun. It then acquires a bluish tinge as it sinks deeper, because the absorption by the broad wings of the neutral sodium lines (the spectral lines responsible for the gloomy orange of sodium street lighting) remove the red and orange from the star light. (more…)

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Scientists Prepare to Take First-Ever Picture of a Black Hole

*The Event Horizon Telescope is an Earth-sized virtual telescope powerful enough to see all the way to the center of our Milky Way, where a supermassive black hole will allow astrophysicists to put Einstein’s Theory of General Relativity to the test.*

Astronomers, physicists and scientists from related fields across the world will convene in Tucson, Ariz. on Jan. 18 to discuss an endeavor that only a few years ago would have been regarded as nothing less than outrageous.

The conference is organized by Dimitrios Psaltis, an associate professor of astrophysics at the University of Arizona’s Steward Observatory, and Dan Marrone, an assistant professor of astronomy at Steward Observatory. (more…)

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Depleted Gas Reservoirs Can Double as Geologic Carbon Storage Sites

*Berkeley Lab scientists help verify science behind geologic carbon sequestration*

A demonstration project on the southeastern tip of Australia has helped to verify that depleted natural gas reservoirs can be repurposed for geologic carbon sequestration, which is a climate change mitigation strategy that involves pumping CO2 deep underground for permanent storage.

The project, which includes scientists from Lawrence Berkeley National Laboratory (Berkeley Lab), also demonstrated that depleted gas fields have enough CO2 storage capacity to make a significant contribution to reducing global emissions. (more…)

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Upper Atmosphere Facilitates Changes That Let Mercury Enter Food Chain

Humans pump thousands of tons of vapor from the metallic element mercury into the atmosphere each year, and it can remain suspended for long periods before being changed into a form that is easily removed from the atmosphere.

New research shows that the upper troposphere and lower stratosphere work to transform elemental mercury into oxidized mercury, which can easily be deposited into aquatic ecosystems and ultimately enter the food chain. (more…)

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Meteorite Shockwaves Trigger Dust Avalanches on Mars

Dust avalanches around impact craters on Mars appear to be the result of the shock wave preceding the actual impact, according to a study led by an undergraduate student at the UA.

When a meteorite careens toward the dusty surface of the Red Planet, it kicks up dust and can cause avalanching even before the rock from outer space hits the ground, a research team led by an undergraduate student at the University of Arizona has discovered.

“We expected that some of the streaks of dust that we see on slopes are caused by seismic shaking during impact,” said Kaylan Burleigh, who led the research project. “We were surprised to find that it rather looks like shockwaves in the air trigger the avalanches even before the impact.” (more…)

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‘Fingerprinting’ Method Tracks Mercury Emissions from Coal-Fired Power Plant

ANN ARBOR, Mich.— For the first time, the chemical “fingerprints” of the element mercury have been used by University of Michigan researchers to directly link environmental pollution to a specific coal-burning power plant.

The primary source of mercury pollution in the atmosphere is coal combustion. The U-M mercury-fingerprinting technique – which has been under development for a decade – provides a tool that will enable researchers to identify specific sources of mercury pollution and determine how much of it is being deposited locally. (more…)

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J. Timmons Roberts: What did Durban do for climate?

J. Timmons Roberts, professor of sociology and director of the Center for Environmental Studies, led a group of Brown researchers and students to the United Nations climate change negotiations in Durban, South Africa. On his return, Roberts spoke with Richard Lewis, reflecting on the Durban meetings, the status of research, and the challenges of activism on issues of climate change.

Timmons Roberts, professor and director of the Center for Environmental Studies, has just returned from attending climate talks in Durban, South Africa. Roberts and a delegation from Brown — faculty, postdoctoral researchers, graduate and undergraduate students — witnessed the negotiations up close as observers to ministerial speeches and negotiations. The talks ended with an agreement to extend the greenhouse gas emissions targets set under the Kyoto Protocol and a pledge to work on a replacement treaty incorporating the United States, China, and India.

Roberts spoke with Richard Lewis on the importance of the talks, the need for industrialized countries to compensate developing countries for damages from climate change, and the unique opportunity for people from Brown’s environmental program to attend the talks. (more…)

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Study: Giant Super-Earths Made of Diamond Are Possible

SAN FRANCISCO – A planet made of diamonds may sound lovely, but you wouldn’t want to live there.

A new study suggests that some stars in the Milky Way could harbor “carbon super-Earths” – giant terrestrial planets that contain up to 50 percent diamond.

But if they exist, those planets are likely devoid of life as we know it. (more…)

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