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Posts Tagged "sun"

Basic Space

Could life arise around a dying star?

White dwarf star Sirius B is roughly the same size as Earth but has a mass 98% that of the sun. Credit: {link url="http://www.spacetelescope.org/images/heic0516c/"}ESA and NASA{/link}

In five billion years the sun is going to blow up into a red giant, then collapse back down again into a white dwarf – a dying star roughly the same size as Earth itself. All of the solar system planets up to, and including, Earth will probably be vaporised during this stellar ballooning. We’ll [...]

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Basic Space

Red Giant Core Spins Ten Times Faster Than Its Surface

Size of the Sun now compared to how big it will expand to as a red giant. Credit: Wikipedia {link url="http://en.wikipedia.org/wiki/User:Mysid"}User:Mysid{/link}, {link url="http://en.wikipedia.org/wiki/User:Mrsanitazier"}User:Mrsanitazier{/link}.

Astronomers have found that the core of a red giant, the type of star that our Sun will eventually become, spins ten times as fast as its surface. And it happens because of a phenomenon we can see here on Earth, too. You have probably seen a figure skater perform a so-called ‘scratch spin’, where [...]

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Life, Unbounded

Don’t Panic, It’s Just A Solar Field Reversal!

Magnetic field lines from active solar regions are drawn over an ultraviolet light image of the Sun (SDO/NASA, K. Schrijver & A. Title, Lockheed Martin)

At any moment the great cocoon of unseen magnetic fields and particle radiation that surrounds the Earth and all other major planets is going to experience a change of polarity. More specifically, the Sun’s polar magnetic field – its magnetic north and south – is going to reverse. This flip happens at solar maximum, the [...]

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Life, Unbounded

We All Carry Stardust Memories

The Trifid Nebula - a potential analog for the kind of place our Sun was formed in 4.5 billion years ago (NASA/ESA)

In lieu of a proper post I thought I’d link to a recent video courtesy of SpaceLab at YouTube. In it you can watch a rather unshaven and scraggly version of me answering a simple but terrific question about the debt we owe to stellar nucleosynthesis. This issue also leads us to think about the [...]

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Life, Unbounded

Venus was Just the Beginning: The Science of Planetary Transits

transit_cartoon.001

Are you sick of reading about the transit of Venus this year? Yes? Me too. But the fact is that when astrophysical objects move between us and something else, like the convenient blaze of a star, there is an extraordinary amount that can be learned. I won’t go far into the delights of a venusian [...]

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Life, Unbounded

The Solar Eclipse Coincidence

Annular eclipse (Credit: sancho_panza)

When the Sun is eclipsed by the Moon this Sunday, for many observers across much of the world it will be temporarily replaced by a beautiful ring of fire – a brilliant annulus of stellar plasma just peeking out around the dark lunar disk. This doesn’t always happen, partial solar eclipses merely trim away a [...]

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Observations

Satellite Gets First Look at Sun’s Tail

The heliosphere

Astronomers just got their first good look in the solar system’s rearview mirror. What they see is a magnetic tail that twists like a corkscrew. Although we tend to think of the sun as stationary with the planets orbiting about it, in fact the solar system is plowing through the galaxy at a million miles [...]

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Observations

Today the Earth Falls Toward the Sun

Sun and Earth from space

Notice anything different today? Is the sun looking a little smaller? Or the Earth moving a little slowly? Well, today is Aphelion Day. Around 11 A.M. Eastern, Earth passes through the point in its orbit that is farthest from the sun, a point called the aphelion. After today, we pick up speed as we fall [...]

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Observations

NASA Adds a New Space Telescope to Its Fleet of Solar Satellites

iris_launch_crop

Despite being the closest star to Earth, the sun still has its secrets. What drives the powerful eruptions of gas known as coronal mass ejections? How does the sun regulate Earth’s climate? Why are the upper layers of the sun’s atmosphere hotter than those next to the surface? Last week’s successful launch of the IRIS [...]

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Observations

Amazing Video of Solar Eclipse Shows Sun’s Structure

Eclipse showing the Sun's chromosphere

This time-lapse video of Sunday’s solar eclipse highlights the Sun’s outer layers: The photographer Cory Poole constructed the video by pasting together 700 photographs taken with a Coronado Solar Max 60 Double Stack telescope. According to Jason Kottke, Poole used a filter that only allows light from hydrogen atoms moving from the 2nd excited state [...]

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Observations

Where Did the Sun Come from? The Search Continues

open cluster Messier 67

We all come from somewhere. If you wind the clock back far enough, we all come from the same place. Sometime about 4.5 billion years ago, the sun was born, and a disk of debris swirling around it soon coalesced into Earth and the rest of the planets. But where did that happen? Where was [...]

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Observations

STEREO spacecraft peek at both sides of the sun at once

STEREO spacecraft A and B on opposite sides of the sun

NASA’s STEREO mission has lived up to its name, placing two spacecraft in position to observe both sides of the sun simultaneously. Most solar missions are in mono, so to speak—they rely on a single observatory, from which only one hemisphere of the sun is visible at any given time. But STEREO comprises twin spacecraft [...]

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Observations

Subatomic sunscreen: How light particles can repair UV-damaged DNA

damage to DNA from uv sunlight

The life-giving sun can be quite rough on genetic material. Most organisms, including plants and many animals, are equipped with a special enzyme in their cells that is quick to repair DNA damage wrought by the sun’s ultraviolet (UV) rays. Humans, however, have less effective repair strategies and as a result are prone to painful [...]

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Observations

NASA’s Solar Dynamics Observatory launches successfully

Solar Dynamics Observatory liftoff

A NASA satellite that promises to deliver an unprecedented volume of data about the workings of the sun launched successfully atop an Atlas 5 rocket Thursday. The Solar Dynamics Observatory, or SDO, lifted off from Cape Canaveral Air Force Station in Florida at 10:23 A.M. (Eastern Standard Time) after a one-day delay due to high [...]

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Symbiartic

SciArt on the Scene in Nov/Dec. 2013

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Ahhh, fall. Time to look for more indoor activities. And aren’t you lucky? Here’s a list of sciart exhibits that will warm your heart while you warm your toes. EXHIBITS: NORTHEAST REGION CLIMATE CHANGE IN OUR WORLD: Photographs by Gary Braasch October 16, 2013 – July 6, 2014 Museum of Science 1 Science Park Boston, [...]

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Symbiartic

Stellar Photography By A Citizen Astronomer

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By now you might be used to spectacular images of celestial bodies thanks to organizations like NASA and the ESA. But it’s still possible to be wowed by these images, especially when they’re taken by people like you and me. Citizen astronomer Alan Friedman takes breathtaking photographs of the sun’s roiling surface from his backyard [...]

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