Where to find life in the Milky Way galaxy

A paper published today on the Los Alamos astro-ph preprint website has attempted to model the habitable zones within the Milky Way galaxy. From the abstract:

We predict that ~1.2% of all stars host a planet that may have been capable of supporting complex life at some point in the history of the Galaxy. Of those stars with a habitable planet, ~75% of planets are predicted to be in a tidally locked configuration with their host star. The majority of these planets that may support complex life are found towards the inner Galaxy, distributed within, and significantly above and below, the Galactic midplane.[emphasis mine]

They took into consideration the hazard of supernovae for killing off planetary life, as well as other factors such as the where the necessary heavier elements would be available for producing planets.

You can download the paper here [pdf].

Highest Water in a Decade Expected at Lake Powell

The highest water level in a decade is expected at Lake Powell by August.

Lake Powell’s rising water level is a result of the long and wet winter this year. An above-average snowpack, with late snows and unseasonably cold weather has lead to a slower melt than usual. As of May, the snowpack that feeds Lake Powell was 30 percent higher than average, with only 50 percent of the accumulated snowpack melted. [emphasis mine]

I thought Al Gore told us this wasn’t going to happen anymore.

A new image of Vesta from Dawn

Dawn continues to approach the large asteroid Vesta. Below is an image taken July 1st from about 62,000 miles. The image has a resolution of 5.8 miles per pixel.

Despite Vesta’s large size, 330 miles in diameter, it is nonspherical. This fact, combined with data that says it is differentiated with a core and mantle, suggests that it is the remains of a larger object that subsequently broke up.

Vesta from 62,000 miles

The painful transition to private space

It appears that U.S. aerospace layoffs more than tripled in the first half of 2011.

The downsizing, prompted by cutbacks in defense and government contracts, jumped from 6,121 in the first six months of 2010 to 20,851 this year, based on planned layoffs announced by major employers.

Though I have always favored shutting down the government space agency and replacing it with privately-built rockets and spaceships, the manner in which this is being done now is disgraceful. George Bush declared the retirement of the shuttle seven years ago. Since then Congress, Bush, and Obama have all done an abominable job preparing the nation for that retirement.
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More stupidity from the Center for Biological Diversity

The Center for Biological Diversity (CBD) today sued the Bureau of Land Management (BLM) in Colorado for allowing caving to take place at the annual convention of the National Speleological Society.

The CBD claims that human activity can spread white nose syndrome, the mysterious ailment that has been killing millions of bats across the eastern United States. To quote:

It is well documented that the fungus believed to cause white-nose syndrome, aptly named Geomyces destructans, can be spread on the clothes and gear of people visiting caves. Scientists strongly suspect that the disease is a recent import from Europe, likely transported by someone who visited a cave there and then came to North America.

To be blunt, this statement is an outright lie.
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Why some space junk is impossible to track

This ISS status update, dated June 28, explains why the piece of space junk that flew past the station that day was such a surprise. (Hat tip to NASA engineer James Fincannon for pointing this out to me.)

Last night at ~6:00pm EDT, NASA Houston FTC (Flight Control Team) received notification of an upcoming “red threshold” conjunction of the ISS with a piece of orbital debris (Object 82618, UNKNOWN), with a TCA (Time of Closest Approach) this morning at 8:08am EDT, – which was too late to begin planning for a DAM (Debris Avoidance Maneuver). Therefore, FTC and crew made preparations for crew sheltering in Soyuz 26S & 27S. PC (Probability of Collision) at last tracking fix (7:20am) remained in the Red box, at ~0.003, with a miss distance of 0.25 km radial, 0.375 km downtrack, 0.570 m crosstrack. The necessary reconfiguration procedures (USOS hatches closed, etc.) began 1.5 hrs before TCA (6:38am EDT), and the six crewmembers ingressed their Soyuz vehicles. At 8:08am the object cleared the ISS with no impact, and shortly thereafter the crew was given the Go for returning to the ISS. [The late notification occurred because of the high air resistance (drag) of the object (~175 times higher than ISS) which made its trajectory very sensitive to small errors in atmospheric density predictions at the current solar flux. Due to the high drag, there is no chance of a recurrence of Object 82618).] [emphasis mine]

In other words, the piece of junk was probably something like a piece of insulation, very light but with a large area, much like a sail. Thus, as it flies through the thin atmosphere at 200 to 400 miles altitude its velocity and direction can easily change, making it difficult, if not impossible, to predict its future trajectory.

The good news is that these same conditions mean that the orbit of the object will quickly decay (“due to high drag”) so that it poses no future threat to the station.

Unfortunately, there are many other objects like this in orbit, and they all pose a threat, mostly because of the difficulty of reliably predicting their orbits.

Another Iceland volcano appears about to erupt

Another Iceland volcano, Hekla, is showing signs that it is about to erupt.

The volcano, dubbed by Icelanders in the Middle Ages as the “Gateway to Hell,” is one of Iceland’s most active, having erupted some 20 times over the past millennium, most recently on Feb. 26, 2000. It measures 4,891-feet (1,491-meters) and is located about 70 miles (110 kilometers) east of Reykjavik, not far from Eyjafjoell.

House proposes to drop NASA’s budget to 2008 levels, eliminate Webb Telescope

The House today proposed cutting NASA’s budget back to 2008 levels while eliminating all funds for the James Webb Space Telescope.

As much as I’d hate to see the Webb telescope die, it has cost far more than planned, is way behind schedule, and carries a gigantic risk of failure. However, if I had a choice, I’d rather they cut the $1.95 billion for Congress’s homemade heavy-lift rocket, the program-formerly-called-Constellation. There is a much better chance that Webb will get completed, launched, and work, than there is for this improvised and impossibly costly Congressionally conceived rocket.

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