Category: Astronomy

Happy Birthday Carl Sagan

Tip of the pipette to Phil Plait for reminding me.

Today, Carl Sagan would have been 75 years old if he had not died in 1996. As a scientist, communicator, and humanist he knew the value of science and the importance of helping people understand its full implications. The notion that we need an army of Sagans to fix the problems with public understanding and acceptance of science is often criticized by communication experts as naive – we need more approaches than just his.

But you know what, it wouldn’t hurt to have a few more Carl Sagans running around. There’s room for some more scientist-communicators like Sagan on this pale blue dot.

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Kepler launches tonight

I had a pleasant surprise in my morning news reading this morning. The Kepler spacecraft has been cleared for launch this evening!

Kepler, named for the early astronomer (and author of the laws of planetary motion), will search for Earth-sized planets with its camera array made up of 42 CCDs. What’s also unique about this spacecraft is that it will take an orbit that trails the Earth, eliminating gravitational perturbations usually experienced in Earth orbit, and the Earth will also block the sun from view. Continue reading Kepler launches tonight

99.7 percent confidence

It turns out that 2007 WD5, the asteroid heading toward Mars, will not hit the red planet. (Darn!) Here’s the Space.com story on the matter, but what I particularly liked was this part:

The new odds were released one day after astronomers with NASA’s NEO office at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., lowered 2007 WD5’s chances of striking Mars from 3.6 percent to 2.5 percent, or about a 1-in-40 chance, on Tuesday. After analyzing results from a new round of observations between Jan. 5 and Jan. 8, scientists now estimate the asteroid will make its closest pass by Mars at a maximum distance of about 16,155 miles (26,000 km).

JPL researchers said that they are 99.7 percent confident that 2007 WD5 will pass no closer than 2,485 miles (4,000 km) from the martian surface.

What you’ve just read was their confidence interval, a statistical concept. Continue reading 99.7 percent confidence

I hope it HITS!

Over the break, I couldn’t help being fascinated by the prospect of an asteroid smacking into Mars. At a 1-in-75 chance, the possible January impact of 2007 WD5 into Mars. Then, the news reported that the chances were tripled! That sounds like a lot, but it just means that WD5 now has a 1-in-28 chance of impact. Doesn’t sound too rosy. However, there’s still time for more observations to be made, and a better estimate to be derived. Or, we could just wait until the 30th of January to find out what happened!

You know what, I hope it hits. Yes, if I had the power to intervene and violate mechanistic causality in the favor of striking the planet Mars with 2007 WD5, I would. By putting it that way, that means I’d be using magic. Why the destructive bent, is this some post-modernist artsy desire? No, it’s science! Continue reading I hope it HITS!

Happy New Year!

Note the timestamp. That’s right, the Sidereal New Year isn’t until 6 pm on January 1st, 2008. That’s because, as each year adds 6 hours, every four years we add one calendar day. Well, the Earth hasn’t gone all the way around the sun relative to the stars (thus, sidereal) until it has taken up those 6 hours for every year. Since 2007 is the third year since the last leap year, then the sidereal new year is 18 hours into the calendar year. As a leap year, 2008 will add another 6 hours to make 24 total hours, but then take them all away with leap year day. Tip to remember: leap years are the only years where the sidereal new year (sun-Earth-stars) and the calendar year (clock-midnight) are the same.

Just another excuse to party. Go here if you want to know more. Much more.