* Astronomy

Blobrana · L

RE: The Earth

Blobrana · L

New theory on Earth's foundations

A team of international researchers, led by Monash University's Dr Wouter Schellart has developed a new global theory of Earth dynamics that explains the motions of the tectonic plates that cover the Earth's surface and the boundaries between these plates.
The new theory has implications for how scientists explain the geological evolution of western North America, including parts of Canada, the USA and Mexico.
The research is published today in the prestigious journal Science.
Read more

Blobrana · L

Goce satellite views Earth's gravity in high definition

This colourful new map traces the subtle but all pervasive influence the pull of gravity has across the globe.
Known as a geoid, it essentially defines where the level surface is on our planet; it tells us which way is "up" and which way is "down".
It is drawn from delicate measurements made by Europe's Goce satellite, which flies so low it comes perilously close to falling out of the sky.
Read more

Blobrana · L

New research may explain mysterious dents in Earth's gravitational field

Scientists have made an advance in understanding the mysterious dents in our planet's gravitational field.
On sailing towards the centre of the Indian Ocean and a loss in one's weight is observed because here the Earth's gravitational field is weaker.
Similar dents in field strength can be observed in the north-east Pacific Ocean and the Ross Sea.
Read more

Blobrana · L

The source of Earth's life-giving water may have been asteroids, astronomers say.
No one knows exactly how Earth acquired more than 300 million trillion gallons of water. The Earth would have been too hot during its formative years to have had oceans from the beginning.
Now, astronomers have found a hint by observing a distant space rock named 24 Themis. There, they found the first indication of water on an asteroid.
Read more

Blobrana · L

University of Calgary scientists probe Earth's core

Listening to earthquake "whispers" reveals new clues about Earth's formation
We know more about distant galaxies than we do about the interior of our own planet. However, by observing distant earthquakes, researchers at the University of Calgary have revealed new clues about the top of the Earth's core in a paper published in the May edition of the journal Physics of the Earth and Planetary Interiors.
Knowledge of the composition and state in this zone is key to unravelling the source of the Earth's magnetic field and the formation of our planet.
Read more

Blobrana · L

Twenty-year study yields precise model of tectonic-plate movements

A new model of the Earth, 20 years in the making, describes a dynamic three-dimensional puzzle of planetary proportions.
Created by University of Wisconsin-Madison geophysicist Chuck DeMets and longtime collaborators Richard Gordon of Rice University and Donald Argus of NASA's Jet Propulsion Laboratory, the model offers a precise description of the relative movements of 25 interlocking tectonic plates that account for 97 percent of the Earth's surface.

"This model can be used to predict the movement of one plate relative to any other plate on the Earth's surface. Plate tectonics describes almost everything about how the Earth's surface moves and deforms, but it's remarkably simple in a mathematical way" - Chuck DeMets,

Tectonic plates are in constant motion, sliding past one another as they float atop the planet's molten interior. The collisions and shifts can create mountain ranges or cause earthquakes like the ones that struck Haiti and Chile this year.

Read more

The MORVEL plate motion project began in the late 1990s via a National Science Foundation grant to professors Charles DeMets of the University of Wisconsin-Madison and Richard Gordon of Rice University. MORVEL consists of a series of angular velocities that describe the geologically recent motions of 25 tectonic plates, as well as the angular velocity uncertainties. It is constructed from marine geophysical, seismologic, and geodetic data from archives and investigators in ten different countries and employs many more data than the NUVEL-1 and NUVEL-1A plate motion estimates, which were published in 1990 and 1994. Finished in 2008 after nearly a decade of intensive data analysis, MORVEL is the most complete, self-consistent geologic plate motion model ever published.
Read more

Blobrana · L

For years science fiction writers and astronomers have speculated about the feasibility of terraforming other planets.
One dream is to make Mars habitable for humans by warming the planet and therefore building up a wetter and thicker atmosphere.
The irony today is that scientists are now talking about "retro-terraforming" Earth of all places! The goal is to try and offset the effects of mankind's contribution to global warming. For example the production of electricity by burning oil and coal accounts for 40 percent of emissions that dump the greenhouse gas carbon dioxide into the atmosphere.
Read more

Blobrana · L

The Early Earth and Plate Tectonics

Click to Play | View Details

Blobrana · L

Earth from Space

This image captures the rugged and remote Kamchatka Peninsula on Russia's East Coast. The 1250-km long peninsula lies between the Pacific Ocean to the east and the Sea of Okhotsk to the west.
The peninsula's fish-like shape is due to its mountain ridges - Sredinny, Valaginsky, Ganalsky and Kumroch - stretching from the north to the south.
Kamchatka is located within the Pacific 'Ring of Fire', a continuous 40000-km-long line of volcanoes and fault lines circling the edges of the Pacific Ocean. There are more than 160 volcanoes, of which 22 are active, on the peninsula. The peninsula contains the Volcanoes of Kamchatka, a UNESCO World Heritage Site.

Source