Category Astronomy/Space

This is an illustration of how the diamond anvil cell is used to mimic and study planetary core conditions. Credit: Stewart McWilliams

Earth’s magnetic field shields us from deadly cosmic radiation, and without it, life as we know it could not exist here. The motion of liquid iron in the planet’s outer core, a”geodynamo,” generates the field. But how it was first created and then sustained throughout Earth’s history has remained a mystery to scientists. New work sheds light on the history of this incredibly important geologic occurrence.

Earth accreted from rocky material that surrounded our Sun in its youth, and over time the most-dense stuff, iron, sank inward, creating the layers that we know exist today–core, mantle, and crust...

The motions of interstellar gas (foreground) seen in contrast to the optical view of the Orion molecular cloud (background). Credit: Stephen Gwyn, Canadian Astronomy Data Centre/National Research Council of Canada (CNW Group/National Research Council Canada)

A new study led by Canadian astronomers provides unprecedented insights into the birth of stars. Using observations from the Green Bank Telescope in West Virginia and the Hawaii-based James Clerk Maxwell Telescope in the United States, astronomers from the National Research Council of Canada (NRC) have discovered that star formation is more regulated by pressure from their surroundings than previously thought.

The birth of stars occurs deep within dense concentrations of interstellar gas and dust—known as cores— when their internal sup...

The Milky Way. Credit: NASA

It is a galactic challenge, to be sure, but Gwendolyn Eadie is getting closer to an accurate answer to a question that has defined her early career in astrophysics: what is the mass of the Milky Way? The short answer, so far, is 7 X 1011 solar masses. In terms that are easier to comprehend, that’s about the mass of our Sun, multiplied by 700 billion. The Sun, for the record, has a mass of 2 nonillion (that’s 2 followed by 30 zeroes) kilograms, or 330,000 times the mass of Earth.

“And our galaxy isn’t even the biggest galaxy,” Eadie says.
Measuring the mass of our home galaxy, or any galaxy, is particularly difficult. A galaxy includes not only stars, planets, moons, gases, dust and other objects and material, but also a big helping of dark matter.

Eadie, a PhD c...

Young star IRAS 14568-6304 is ejecting gas at supersonic speeds and eventually will have cleared a hole in the cloud ESA/Hubble & NASA Acknowledgements: R. Sahai (Jet Propulsion Credit: Laboratory), S. Meunier

This young star is breaking out. Like a hatchling pecking through its shell, this particular stellar newborn is forcing its way out into the surrounding Universe. The golden veil of light cloaks a young stellar object, IRAS 14568-6304. It is ejecting gas at supersonic speeds and eventually will have cleared a hole in the cloud, allowing it to be easily visible to the outside Universe.

Stars are born deep in dense clouds of dust and gas. This particular cloud is known as the Circinus molecular cloud complex. It is 2280 light-years away and stretches across 180 light-years of space...