Tag: science

IPCC meeting ends with few changes or reforms

9:23 am

You call this reform? At the just completed annual meeting of the IPCC in South Korea, the panel refused to remove its controversial chairman, Rajendra Pachauri, while recommending a few minor reforms in how the panel writes its reports. This quote indicates just how unserious the IPCC is about reform:

In the past, he said, IPCC reports sometimes projected the likelihood of potential climate-change effects, such as melting glaciers, without enough evidence. “There were some weaknesses in the application,” said [Chris Field, a U.S. scientist and a leader of the panel’s 2014 report].

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Dried up lake beds on Mars?

8:55 pm

A paper published on Saturday in the Journal of Geophysical Research – Planets of the American Geophysical Union, scientists suggest that the polygonal shaped cracks seen in the crater floors on many Martian craters could be evidence of ancient lakes. The evidence also suggests that the lakes were formed by the impact that created the crater. The energy of the impact melted underground ice to form a temporary lake inside the crater, which eventually dries out, leaving behind the polygons. From the abstract:

We propose desiccation to be a dominant mechanism for the formation of Crater Floor Polygons without ruling out thermal contraction as a possible contributor in some cases. This implies that lakes or water-rich sediments occupied the craters in the past. Many such aqueous environments have no apparent external source of water, and thus, hydrothermal processes occurring shortly after the impact event may be viable explanations for the observed evidence.

Crater floor polygons on Mars

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A wish list of spectacular future planetary missions

5:01 pm

Steve Squyres of Cornell University and the project scientist of the Mars rovers Spirit and Opportunity spoke today at an astrobiology symposium in Arlington, Virginia. He described several spectacular planetary missions that might be flown in the coming decade. All are being considered. None have yet been chosen or funded.

  • A mission to grab a sample from a comet and return it to Earth.

  • A mission to put a rover or lander on one of the poles of Mars to study the frozen layers of water under the icecap.

  • Mars sample return mission. This mission is so difficult and expensive that it probably would be broken down into three parts:

    • Two rovers on the surface to gather and cache sample material.

    • A lander/rover mission to grab the samples and bring them up to Mars orbit. “Putting into orbit a precious cargo the size of a coconut,” Squyres said.

    • A mission to grab the sample cargo in Martian orbit and return it to Earth.

  • An orbiter to study both Jupiter and its moon Europa.

  • An orbiter to Enceladus, the moon of Saturn, to study the water and organic chemistry in its mysterious plumes.

  • An orbiter to Titan, with balloon to probe the atmosphere as well as a “lake lander, a boat” to study Titan’s lakes.

  • A variety of landers and rovers to go to Venus. One of the more astonishing mission concepts would land, then take off again to visit different places on the surface.

Squyres is the co-chair of a committee of the National Science Foundation that is right now putting together a decadal survey for outlining unmanned planetary research for the next decade. This survey is expected to be released in March, which is when we will find out which of the above missions the planetary science community prefers.

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Hubble tracks the aftermath of a possible asteroid collision

10:05 pm

Using the Hubble Space Telescope over the last ten months, astronomers have tracked the decaying aftermath of a possible asteroid collision. Key quote:

Astronomers think a smaller rock, perhaps 10 to 15 feet wide, slammed into the larger one. The pair probably collided at high speed, about 11,000 mph, which smashed and vaporized the small asteroid and stripped material from the larger one. Jewitt estimates that the violent encounter happened in February or March 2009 and was as powerful as the detonation of a small atomic bomb.

The image sequence below, taken from the original paper describing the discovery [pdf], shows the slow changes that have occurred since January. At the moment scientists do not have an satisfactory explanation for the nucleus’s X-shaped pattern in the earliest images.

sequence of images of disrupted asteroid

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APS responds to Harold Lewis’s resignation letter

10:16 am

The American Physical Society has responded to Harold Lewis’s resignation letter.

It appears from their response that they are feeling some pressure about their past position, which stated “The evidence is incontrovertible: Global warming is occurring.” Compare that with what they say now, in their response to Lewis:

APS continues to recognize that climate models are far from adequate, and the extent of global warming and climatic disruptions produced by sustained increases in atmospheric carbon loading remain uncertain.

How nice. A science organization recognizing the uncertainty of science!

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Asteroids of note

3:58 pm

At today’s press conference at the 42nd meeting of the AAS Division for Planetary Sciences, the topic was asteroids, including one which holds the possibility of hitting the Earth.

  • 65 Cybele has been found to have water ice and organic molecules on its surface, the second such asteroid so found. Key quote from the abstract:

    We conclude that 65 Cybele is covered by fine anhydrous silicate grains, with a small amount of water-ice and complex organic solids. This is similar to comets where non-equilibrium phases coexist, e.g. water-ice and anhydrous silicates; thus we conclude that this is a very primitive object.

    According to Humberto Campins of the University of Central Florida, this combination of water and organics could become hospitable to life should some form of energy be added, such as an impact to the asteroid.

  • The origin of the asteroid Phaethon, cause of the Geminids meteor shower, has been traced to the Pallas family of asteroids, a family created by the debris thrown out during a crater impact on the large asteroid Pallas. Campins also noted that this proves Phaethon is an asteroid and not a comet, a question that astronomers had been debating beforehand. Read the abstract here.
  • Asteroid 1999 RQ36, which has a 1 in a 1000 chance hitting the Earth in 2182 and is also the prime target of a proposed NASA sample return mission, has now been determined to be a member of the Polana family of asteroids. This makes 1999 RQ36 a very primitive asteroid from the very beginnings of the solar system. Moreover, this suggests that the Polana family could be the “most important” source of many near Earth asteroids. The abstract can be found here.
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The basic ingredients of life might exist in Titan’s atmosphere

3:40 pm

Big news! In a simulation of the upper atmosphere of Titan at about 600 miles altitude, scientists have discovered the basic ingredients of life are quickly synthesized when exposed to the kind of hard radiation found there. Key quote from the press release, issued today at the 42nd meeting of the AAS Division for Planetary Sciences:

The molecules discovered include the five nucleotide bases used by life on Earth (cytosine, adenine, thymine, guanine and uracil) and the two smallest amino acids, glycine and alanine.

For those who don’t remember their high school biology, these nucleotides are the building blocks of DNA.

The abstract of the scientist’s work can be found here.

What the scientists did was recreate the basic ingredients of Titan’s upper atmosphere, comprised of nitrogen, methane and carbon monoxide. Cassini data has shown that within this atmosphere are very large molecules, as yet unidentified.

The scientists then bathed their recreation in the kind of intense radiation expected at that altitude, and amazingly produced the complex organic molecules that are basic to life. Moreover, the experiment was the first to produce these complex molecules without the presence of water, something that scientists have previously thought was required. These results suggest that in addition to forming in the oceans, life could also form in the upper atmospheres of planets.

This result also suggests strongly that it is incredibly easy to produce the basic building blocks of life, almost anywhere in the universe where organic molecules are present.

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Pluto’s ice: 97% nitrogen, 3% methane

4:00 pm

More results from the press conference going on right now at the 42nd meeting of the AAS Division for Planetary Sciences:

Pluto’s surface ice is made up of 97% nitrogen, 3% methane, while the surface of the Kuiper Belt object Eris (which is larger than Pluto) is even more rich in methane, with a make up of 90% nitrogen and 10% methane. Both measurements go down to a depth of about 10 inches. To see the abstract for this result, go here.

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The atmosphere of Venus is 60% less dense at its poles

3:01 pm

By diving into the upper atmosphere of Venus above its north pole, Venus Express has found that the atmosphere there is 60% less dense than predicted. This from a press conference going on right now at the 42nd meeting of the AAS Division for Planetary Sciences. They plan an additional dive campaign during the next month. And they plan more dives, going deeper each time, as they judge the consequences to the spacecraft each time.

To read the abstracts of the Venus Express papers, go here.

Updated: The full press release, with images, can be seen here.

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The October 2010 sunspot graph

10:46 am

Yesterday NOAA’s Space Weather Prediction Center published its October monthly graph, showing the sun’s developing sunspot cycle in comparison with the consensis prediction made by the solar science community in May 2009.

October Sunspot graph

Sunspot activity in September clearly jumped, though it still remains far below predictions. Prepare for the weakest solar maximum since the 1810s!

Note also that today the Sun is blank, with no sunspots, the first time this has happened since August. At that time I speculated that this might “be the last time the Sun will be blank for years as it continues to ramp up to its next solar maximum.” Obviously not. The question now is whether today will be the finale in blankness for this minimum.

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Murder for the sake of climate idealogy

5:13 pm

Bumped. Scroll down to see the update.

This video has been making the rounds on the web. Though I warn you that is somewhat graphic, it is essential that you watch it.

When I first saw this about a week ago, I didn’t quite know what to make of it. It was so vile and offensive I could not believe that it was legitimate. It obviously wants to pay some homage to Monty Python, but even Monty Python never went this far. How could anyone possibly think that killing small children in the name of environmentalism was in any way funny? And how could anyone ever believe that this video would persuade anyone to go along with the 1010 environmental campaign? If anything, the video does an excellent job of discrediting this organization and everyone involved with it.

Thus, despite what some bloggers were saying, I held back commenting, just to make sure the video was real and not a terrible prank meant to sabotage.

There is now no reason to hold back. Late last week, the 1010 organization itself issued an apology, admitting that this video was their handiwork. Before I continue, I think it is worthwhile for you to also read their apology, in all its venal glory. In many ways, it condemns them and their allies far more than the video did:
» Read more

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WISE telescope moves into final phase of mission

2:18 pm

Having run out hydrogen coolant for its infrared cameras and with only a few more months of usable life, the Wide-Field Infrared Survey Explorer (WISE) has shifted its work from deep space astronomy to completing its last sweep of the solar system in a search for asteroids and comets.

Update: At a press conference going on right now at the 42nd meeting of the AAS Division for Planetary Sciences, WISE scientists note that the mission extension will continue for one month. If that month is successful, the mission will continue until the end of January 2011 in order to complete its solar system sweep. After this the spacecraft will be put in hibernation, available for future work.

Summary of solar system results so far:

  • 33,576 asteroids discovered of which 120 were Near Earth Asteroids.
  • 19 new comets.
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