Will all the talk about what constitutes a planet last week, let’s pay a visit to some newly discovered objects out there in the universe that are quite unusual. Dubbed ‘planemos’ – or planetary mass objects, these twins orbit each other in the depths of space, with no parent star holding them in gravitational thrall. Is it still a planet with a sun?
- Astronomers Capture Meteorite Strike On Moon – This is a cool little story. Scientists are monitoring the moon for meteorite strikes as part of NASA’s plans to return to the moon for a long term exploration. Since the moon lacks a protective atmosphere, even small bits of rock impact the surface. NASA wants to know how often these impacts occur, so the agency is funding a project to monitor the moon with telescopes. Almost from the start, researchers caught this impact on May 2, 2006 in the Sea of Clouds (Mare Nubium). They estimate it was a 25 cm meteoroid travelling at 38 km/s and that it carved out a 14 meter wide, 3 meter deep crater. FYI, 38 km/s is 85,000 mph.
- Upper Limit For Moons Explained – It’s an interesting conundrum; Jupiter, Saturn and Uranas all have dozens of moons, yet in each case the combined mass of the moons equals 0.01% of the parent planet. Well a new model seeks to explain how these gas giants garnered such an array of moons. Basically any moon larger than this 0.01% limit was drawn too close to the gas giant and absorbed into the planet. The only exception to this rule was Neptune’s moon Triton, which astronomers think is a captured object that did not form with Neptune.
Some interesting stories floating around on the internet lately:
- Tomb of Xena uncovered in Peru – Archaeologists unearthed a Moche woman’s tomb in in northern Peru, revealing a rich trove of grave artifacts and weapons. Speculation abounds that she was a tattooed warrior woman, an unprecedented find in South American anthropology.
- Three Gorges Dam set for completion – Well I guess I’ll never get to the the famed Three Gorges of the Yangtze. The dam is just about finished, with the last concrete being poured this weekend.
- Solar system discovered – Astronomers located a solar system containing three rocky, medium sized planets. 3 planets the size of Neptune and an asteroid belt are orbiting the star HD69830, about 41 light years away in the constellation of Puppis. The furthest planet is in the habitable zone of the star, and could harbor liquid water.
- Ancient Egyptian colonialism – In 1550 B.C., ancient Egypt conquered the kingdom of Nubia. A newly discovered cemetery revealed that Egypt absorbed Nubians into the imperial hierarchy. Several high status officials were buried in the cemetery, and most of them were local Nubians. They were uniters, not dividers.
- Our muddled ancestry – So there was significant interbreeding between human and chimpanzee ancestors several million years ago. Maybe I am a monkey’s uncle.
- AMD rolls out 64 bit, dual core laptop processor – I think my next computer will be powered by AMD. They are making some really powerful chips.
- Real Time Satellite Tracking – This is cool, really cool. Coolest link here. Using Google Maps data, track satellites as they orbit overhead. Best fun is zoom in on hybrid mode and watch how fast the ISS space station hurtles across the landscape.
- Worst president ever? – Finally, it’s not science related, but I was amazed by this quote in the Rolling Stone article:
According to the Treasury Department, the forty-two presidents who held office between 1789 and 2000 borrowed a combined total of $1.01 trillion from foreign governments and financial institutions. But between 2001 and 2005 alone, the Bush White House borrowed $1.05 trillion, more than all of the previous presidencies combined.
That just flabbergasts me. Can this be true? Holy guacamole, that’s a real accomplishment.
Because they’re out of a job. There are no UFO’s, it’s all in people’s heads.
I wanted to mention this last week when it first circulated around the web, but Astronomy Picture of the Day prompted me to remember. Check out this spectacular movie of Huygens’ descent through the orange haze of Titan in January 2005; the first views of an alien world. Amazing.
Another good site on this historic event is the NOVA web site, Voyage to the Mystery Moon.
Guess what I’ll be doing tonight: eyeballing Jupiter through my telescope. Though it is looking rather cloudy outside right now, not a good omen.
Figures. It’s been clear and cool most nights for the past month, and tonight it looks like rain.
Time for a random smattering of links as I clear some tabs off of Camino:
- Scientists penetrate fossil magma chamber beneath ocean crust – drilling more than a mile through the ocean floor, geologists drilled through volcanic rock to reach an ancient magma chamber beneath the ocean’s surface. Remember that movie The Core? I wonder if it was like that?
- A survey of open source applications for Mac OS X – Fink and DarwinPorts, more software than you can shake a stick at. And it’s all free.
- Vibramfivefingers – A bootie with toes, it’s supposed to fit the foot like a glove. Looks freaky deaky to me.
- US Navy obsolete in War on Terror – Another example of that old aphorism that the military always prepares to fight the last war. The world’s most powerful navy has nobody to fight.
- More evidence for Nemesis? – That’s Nemesis, the undiscovered companion star of our Sun. The chief proponent of this theory says that newly discovered Sedna orbits in resonance with previously published orbital data for this undiscovered star.
- Nile explorers relate their adventures – Rousing adventure tale on the National Geographic website. Wonder how long before it is featured on the National Geographic Channel?
- Citizen Cope – Been listening to this guy a lot lately. Once I get my iBook back from Marianas Electronics I think I’ll pay a visit to the iTunes Music Store.
- Itchy ‘N Scratchy – Yeah, I got jafjaf. That reminds me, I need to go take my prescription for this.
- Odd man out in a cut-throat world – Now there’s a bookstore I wouldn’t mind working in for a few years.
- Kryptos confounds sleuths – because of a typo – The mysterious sculpture Kryptos adorns an atrium on the grounds of the CIA in Langley, Virginia. For sixteen years it has stymied cryptographers attempting to decipher the code encrypted across the undulating surface. Turns out there’s a good reason why: the artist made a typo.
- Surprise! Bugs at airport blamed on Yingling – Boy, I didn’t see that coming from a mile off.
- Warcraft III – Been thinking about actually buying a video game. Of course, it’s three or four years old, but it still looks cool. And it’s cheap…
- Nepalis celebrate – Looks like the king caved in and recalled parliament after several years. Hopefully this calms the situation in Nepal.
- The English laugh at our low gasoline prices – They pay $8 a gallon in merry old England for petrol.
- CNMI mentioned in Alternet – a look at Jack Abramoff’s dealings with the Northern Marianas and guest workers.
- Gas prices spurring ‘moped madness’ – I must admit, I’ve been thinking about buying a motorcycle. The incredible mileage is hard to beat, but frankly it would suck to ride a bike on Guam in August.
- Apocalysts now – Finally, how about a screed against George W. Bush’s religious overtones? Nothing like scaring the atheists and riling up the devout.
Speaking of Mars, there’s been some fascinating developments over the red planet. Looks like a mineralogical report release last week lays out the Martian geological history, and it is a dry and dusty story.
The Mars Express orbiter arrived in orbit around the red planet in late 2003, and mapped the planet’s surface in excruciating detail. The OMEGA instrument created mineral maps that suggest three distinct eras on Mars; an initial warm and wet period, a fiery volcanic interlude, and the long deep freeze that continues today.
The OMEGA team, led by Jean-Pierre Bibring of the Institut d’Astrophysique Spatiale in France, found about two dozen sites rich in clay minerals, which form in water and in conditions of low acidity. These sites are scattered around the planet in ancient craters and where an overlying layer of volcanic cover or wind-blown sand and dust has been removed.
That suggests the clays formed early in the planet’s history, says Bibring: “The clays may have been formed on a large scale but we only see them where they have been exposed by erosion, outflows, or impacts.”
The spectrometer also found sulphate minerals, such as gypsum and grey haematite, concentrated in a few places. These locations include Valles Marineris – the Red Planet’s “Grand Canyon” – and Meridiani, where NASA’s Opportunity rover landed and also found sulphate-rich rocks. Sulphates require water to form, but some detected by OMEGA must also have been created in acidic conditions.
Finally, OMEGA found minerals rich in ferric oxides that had not been altered by water. These minerals are found over most of the planet and are thought to be caused by the slow weathering of rocks through chemical interactions with the atmosphere.
This mineral evidence ties in with current thinking about the planet’s history. For the first 600 million years, Mars had a warm and wet atmosphere and large bodies of surface water, conditions ripe for the development of life.
Then the eon of supervolcanos began. Massive Olympus Mons and the Tharsis Bulge speak to the size and power of this volcanic era. The volcanism release huge amounts of sulphur into the atmosphere, creating sulphuric acid and covering the surface of Mars in sulphates that require acidic water to form. This lasted for approximately 500 million years.
Finally, the failing heat of the planet’s core shut down the volcanism and the internal dynamo that generated Mars’ magnetic field collapsed. The atmosphere, exposed to the solar wind, bled away into outer space like fog dissipating on a sunny morning. The loss of atmospheric pressure put Mars into a deep freeze, desiccating the planet’s surface for 3.5 billion years.
Scientists are most interested in those early clay layers which formed during the wet and warm period. The Mars Reconnaissance Orbiter will probably focus its big cameras on those regions, looking for evidence of the planet’s brief springtime and the possibility of life.
If liquid water still exists, it lies beneath the ice just like those lakes in Antarctica. The surface of Mars is an inhospitable, dry frozen wasteland, bathed in solar radiation.
Yesterday’s Astronomy Picture of the Day is a cool multiple exposure time lapse of the retrograde motion of Mars. Check it out.
Our planet is rapidly Approaching Mars, which means the red planet is getting bigger and brighter in the night sky. Closest approach comes in October, when the two planets will only be 69 million kilometers apart.
This conjunction is the best time to launch spacecraft to Mars, and NASA will launch another orbiter in August. The Mars Reconnaissance Orbiter will bring the most powerful camera yet into orbit around the red planet, along with subsurface scanning radar to seek out water deposits beneath the parched surface of the planet.
From the BBC comes this cool little picture. Novel view of Martian spacecraft – The Mars Global Surveyor successfully imaged the Mars Odyssey probe in Martian orbit. It is the first picture of a spacecraft orbiting an alien world, taken by another craft circling the same planet.
The two orbiting satellites occasionally come within 15 kilometers of each other, despite having different orbits around the red planet.
The Mars Global Surveyor also imaged the ESA’s Mars Express satellite in orbit around Mars too.
Okay, that’s a pretty bad pun. NASA is set to launch another amazing probe into space next year, the Dawn Mission to Ceres and Vesta, the two largest objects in the asteroid belt between Mars and Jupiter. I was excited about the impending New Horizons mission to Pluto and the Kuiper Belt, but this adventure will be just as exciting. The asteroid belt is one of those great mysteries of the solar system. How did the asteroids form? Why isn’t there a planet there?