Check out episode 5 of Walkabout the Galaxy and subscribe to our podcast. In this episode, guaranteed to be the newest one until the next episode, Josh, Addie and Tracy discuss the original Wiener, getting sliced into tiny pieces, and then there’s a bit about the LADEE mission to the Moon as well.



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Here’s the thing. I’ve wanted to write a book, but the internet provides a great mechanism for writing shorter pieces. That is how this blog was originally born. Since my career cup has been running over, I’ve had less time to post reviews, science articles, and other observations here. But when I had more time I did write an autobiographical essay, and with the advent of e-readers I’ve finally updated it and packaged it, and now here it is for Kindle at Amazon.

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I have to give a plug to Aylia Colwell’s hilarious videos. Check out her most recent one here.

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Going to Vasquez Rocks is a pilgrimage for Trekkies, and I finally made it there with my daughter and sister-in-law. Most famous (to Star Trek fans) as the site of the battle between Kirk and the man-lizard Gorn captain in the episode “Arena”, Vasquez Rocks was also the site of location shots for three other Original Series episodes as well as a variety of episodes from later series. But it was the iconic scenes from the Original Series that made it such a geeky blast to go there.

I thought about going to the top of the rocks where Kirk dislodges a boulder to try to kill the Gorn, but about halfway up I realized that (a) the rocks were quite steep after all, (b) my shoes were made for walking, not climbing, and (c) it would be rather easy to get some nasty cuts and bruises with a simple misstep. I felt a bit better about my caution when a later viewing of “Arena” shows that it must be a stuntman we see run up there. I had a great time running around with my tricorder and communicator and my daughter in her homemade Nurse Chapel uniform while Sue dutifully snapped pictures. I need a return trip with a bit more time to find some of the less-obvious scenes from “Shore Leave”, “Friday’s Child” and “The Alternative Factor”.

Thinking better about going to the top.
Thinking better about going to the top.
Trying to get in touch with the Enterprise.
Trying to get in touch with the Enterprise.
Face off
Face off

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My Erdös-Bacon number is 6. This is the sum of my Erdös number (4), which measures the number of degrees of separation I have, through authorship of academic papers, from prolific Hungarian mathematician Paul Erdös, and my Bacon number (2), which measures the number of degrees of separation I have, through movie roles, from American actor Kevin Bacon. My Bacon number is low courtesy of my role in the movie Deep Impact which features a large cast of many veteran actors. My connection to Bacon (or at least the first one I found) is via Maximilian Schell, who was in Telling Lies in America with Kevin Bacon. So Schell has a Bacon number of 1, and since I was in Deep Impact with Schell, I have a Bacon number of 2.

Figuring out my Erdös number required a bit more sleuthing, but was greatly aided by this website, provided by the American Mathematical Society, which will provide the Erdös number of any author in the database of math papers. The difficulty is that I am not in their database. So I made some guesses as to co-authors of mine who might be in their database. The first good hit was Frank Spahn, a dynamicist friend and colleague at the University of Potsdam who has an Erdös number of 5, giving me E=6 and and E-B number of 8. When I thought about other possible connections, though, I hit on Jeff Scargle, a mathematically inclined planetary scientist at NASA’s Ames Research Center. While I have not authored a paper with Jeff Scargle, I have with his Ames colleague, Jeff Cuzzi. Scargle is in the database with an Erdös number of 2, giving Cuzzi an Erdös number of 3, and me E=4.

Why does anyone care about these numbers? Well, most don’t. The idea of degrees of separation has been around for some time, and a game was created around the idea of finding the number of acting degrees of separation from Kevin Bacon. These calculations of degrees of separation are a way to quantify the “small world phenomenon” that posits that the human population is a network of connections where the number of links between any two individuals is small. The world of mathematical journals is sufficiently different, that even having an Erdös number and a Bacon number is fairly unusual. And since the whole connection concept is essentially a mathematical model, it seems fitting to have a small world number based on a mathematician. Paul Erdös wrote well over 1000 scholarly articles, so mathematicians used him as a root for degrees of separation in that particular world. My E-B number of 6 puts me one behind Brian Greene (5) and one better than Stephen Hawking and tied with Richard Feynman.

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I completed my seventh lifetime parabolic flight on Sunday, but first flight with the Zero-G corporation. While my earlier flights on NASA’s KC-135 (now retired and replaced by a C-9) involved anywhere from 36 to 51 parabolas, Zero-G does only 15 parabolas on non-research flights. They also currently have a contract to sell flights to NASA, and I think those do the full set of 40-50 parabolas, but the flight I was on Sunday was sponsored by Space Florida for educators, and operated in pretty much the same mode as their passenger flights. The limited number of parabolas is to limit motion sickness. As someone who has gotten violently ill on the longer flights, I think this is a good idea. Paying five grand (their current ticket price) to get violently ill, even with the unique experience of weightlessness, would probably leave a lot of customers grumpy.

Their flight plan begins with one parabola simulating at martian gravity followed by two “lunars”. Parabolas are flown in groups of three followed by a couple of minutes of straight and level flight to get set up for the next set.

ZG-210 Silver Team

The Silver Team poses in front of “G-Force-One” prior to our flight on Sunday December 7 at the Space Coast Regional Airport.

I took on board one of the impact experiment chambers from my earlier “Physics of Regolith Impacts in Microgravity Experiment” (PRIME) to do a test run. The experiment basically consists of shooting a marble into a tray of sand at very low speeds in microgravity and measuring the speed and quantity of material ejected. However, because this was being flown as a commercial flight rather than a government flight, it was not possible to evacuate the test chamber. The test material floated out of the target chamber, limiting the amount of ejecta. However, this provided a fairly dramatic demonstration of the effects of air as a lubricant for granular materials and underscores the need for evacuated test chambers on future flights.

PRIME Experiment on ZG-210

I give the thumbs up after successful operation of the PRIME test.

I also tried to do a simpler experiment for classroom demonstration of equipartition of energy in a granular gas. That’s a fancy way of saying “watching different-sized marbles bounce around at different speeds”. This was compromised by the lack of foot restraints on the plane and the general chaos of floating bodies throughout the plane volume. Nevertheless, I think I got some good video.

Granular Experiment on ZG-210

My marble experiment is behaving fine, but my body won’t hold still.

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I was elected to the DPS committee this week for a three-year term beginning at the next meeting of the DPS (Division for Planetary Sciences of the American Astronomical Society) in October at Cornell University. I pledge to do everything in my power to lower gas prices and bring the troops home from Iraq.

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Today’s launch of the space shuttle Discovery was our first attempt to view the ascent literally from our back yard. The shuttle was clearly visible for more than a minute, rising high above the horizon on a column of flame and smoke before disappearing behind a cloud shortly before solid rocket motor separation.

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This is a very cool and very fun visualization tool that lets you ride along with the Cassini spacecraft as it tours the Saturn system. The path of the spacecraft as well as the pointing of the spacecraft, are taken from the actual data files describing Cassini’s activities. Check it out.

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These amazing video tests of chimpanzee visual recall show to my amateur eye that chimps process and retain the visual field in a way that is different than humans. Some explanation and commentary on the significance of the results can be found in this New Scientist article. As Darth Vader said, “Impressive. Most Impressive.”

Average Rating: 4.9 out of 5 based on 258 user reviews.