USGS Astrogeology Hot Topics - Odds and Ends

NASA Image of the Day: Flagstaff area volcanoes

nospam@example.com (BlogAdmin) — Tue, 31 Jul 2007 19:12:50 -0700

Today's NASA Image of the Day is a rendering of the San Francisco volcano field, the home of Flagstaff, Arizona.

ASTER perspective was created by draping ASTER image data over topographic data from the U.S. Geological Survey National Elevation Data.

Image credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

From the NASA Image of the Day site: Northern Arizona is best known for the Grand Canyon. Less widely known are the hundreds of geologically young volcanoes, at least one of which buried the homes of local residents. San Francisco Mountain, a truncated stratovolcano, was once a much taller structure before it exploded some 400,000 years ago a la Mt. St. Helens. The young cinder cone field to its east includes Sunset Crater, that erupted in 1064 and buried Native American homes. This ASTER perspective was created by draping ASTER image data over topographic data from the U.S. Geological Survey National Elevation Data.

Continue reading "NASA Image of the Day: Flagstaff area volcanoes"

Solar System Poetry

nospam@example.com (BlogAdmin) — Tue, 19 Jun 2007 09:46:10 -0700

Stuart Atkinson, a U.K. writer and amateur astronomer, maintains a blog of his beautiful solar system poetry called The Verse. A snippet from his poem entitled "Titan":

The first time I saw you
I was twelve. Standing alone
In the crisp Christmas snow, eyes watering
With the cold I peered into my new
Telescopes eyepiece and there you were:
A tiny golden? glint, a hint,
A spark of light beside
The badly-focussed globe of Saturn.

Looking at you even then I knew
That moon was far too shy a word.
Centuries of spying on you
Had revealed to Man the Truth,
That you were a World, a Planet
In all but name. Plaque-carrying Pioneers
And Voyagers had already sailed past you,
Cameras clicking in the cold
Of space, but your face remained
Hidden beneath that veil of ochre,
Choking cloud; our first emissaries found
No Mariner mountains poking through

Read more on The Verse...

Star Shade Could Reveal Earthlike Exoplanets

nospam@example.com (HotTopicsJournalist) — Mon, 17 Jul 2006 14:00:30 -0700

Image: © AMY LO

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Stars shine so brightly that any planets orbiting them are lost in the glow. In fact, astronomers can only detect exoplanets indirectly by their effects on parent stars: either gravitational or, as the planet passes in front, by dimming. But a 50-meter-wide, daisy-shaped star shade could block stellar light, allowing direct observation of their planets, according to a new paper in today's Nature.

Webster Cash of the University of Colorado designed the star shade to be used in conjunction with orbiting telescopes. The thin plastic shade would cancel out a specific star's light and the telescope--trailing 15,000 miles behind--could then take in light from its distant planets. "Think of an outfielder holding up one hand to block out the sunlight as he tracks a fly ball," Cash explains. "We would use the star shade as a giant hand to suppress the light emanating from a central star by a factor of about 10 billion."

Read More: Scientific American.com -Star Shade Could Reveal Earthllike Exoplanets

Happy 4th of July from USGS Astrogeology!

nospam@example.com (BlogAdmin) — Fri, 30 Jun 2006 16:00:00 -0700

Happy Independence Day!

Somebody Define Planet, Please

nospam@example.com (HotTopicsJournalist) — Tue, 20 Jun 2006 15:25:59 -0700

Artist concept of 2003 UB313

(also known as the "10th" planet)

Credit: Robert Hurt (IPAC)

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The International Astronomical Union (IAU) will be meeting this August to hammer out the final definition of the word "planet." If approved, the definition will be announced in September.

Webster defines the word planet as: any of the seven celestial bodies sun, moon, Venus, Jupiter, Mars, Mercury, and Saturn that in ancient belief have motions of their own among the fixed stars b (1) : any of the large bodies that revolve around the sun in the solar system (2) : a similar body associated with another star.

So one might ask, what's the big deal? Apparently it's UB313, an object roughly the size of Pluto that orbits the Sun beyond Neptune. The object's discoverer, Mike Brown of Caltech, has argued it should be called a planet. Some astronomers say if UB313 is a planet, then several similar bodies should gain the same status. The number of planets in our solar system could ultimately climb into the thousands as technology improves.

What will the definition be? Will they scratch Pluto from being a planet? What qualifiers will they use to rewrite this definiton? Will they look at mass? Some have wondered if they in fact would include orbit characteristics and formation scenarios? I suppose we won't know until the new committee that includes historians and educators, make their recommendation to the IAU in September. Mark your calenders.

A Baby Crater is Born

nospam@example.com (HotTopicsJournalist) — Tue, 13 Jun 2006 17:36:01 -0700

On May 2, 2006, a baby crater was born on the Moon. NASA says its about 14 meters wide, 3 meters deep and precisely one month, eleven days old. What a baby!

NASA astronomers watched a meteoroid hit the Moon's Sea of Clouds (Mare Nubium) with 17 billion joules of kinetic energy.

Bill Cooke, the head of NASA's Meteoroid Environment Office in Huntsville, Alabama said that the impact created a bright fireball, which was video-recorded using a 10-inch telescope. Stuff hits the Moon all the time," said Cooke--but this is the best-ever recording of an explosion in progress."

Show me the impact and tell me the full story!