### Feature Article

Wow, it has been a while since I last posted. Sorry for the hiatus, but I've been on the road giving talks and observing, all the while writing papers and proposals.

Speaking of writing, last year I was invited to write a cover story for Sky & Telescope about the relationships between planets and their central stars. Different types of stars provide us with different opportunities to learn about planets. For example, stars more massive than the Sun are much more likely than dinky little red dwarfs to harbor a Jupiter-sized planet. This correlation between planet occurrence and stellar mass gives us clues about how planets form. However, if you want to find low-mass planets, the signposts of a planet's presence are much easier to read around M dwarfs (an eclipsing planet dims a small star more than a big star; small planets induce larger accelerations in smaller stars).

All this and more can be found in the April issue of Sky & Telescope. Grab a copy soon!

UPDATE: For some reason I cannot find the article in the online edition of S&T. But the print version should be on newsstands through the end of March (even though it's the April issue).

jcom said…
JohnJohn that is AWESOME, congrats! Can't wait to read the feature article that gets its own cover and everything. Somebody drew a picture of a planet with two moons and a volcano just for you!!!
blissful_e said…
Yea! Congrats on the feature article!

My kids think *our* planet has two moons... they see one, then another as they round the corner of the house. :)

### On the Height of J.J. Barea

Dallas Mavericks point guard J.J. Barea standing between two very tall people (from: Picassa user photoasisphoto).

Congrats to the Dallas Mavericks, who beat the Miami Heat tonight in game six to win the NBA championship.

Okay, with that out of the way, just how tall is the busy-footed Maverick point guard J.J. Barea? He's listed as 6-foot on NBA.com, but no one, not even the sports casters, believes that he can possibly be that tall. He looks like a super-fast Hobbit out there. But could that just be relative scaling, with him standing next to a bunch of extremely tall people? People on Yahoo! Answers think so---I know because I've been Google searching "J.J. Barea Height" for the past 15 minutes.

So I decided to find a photo and settle the issue once and for all.

I then used the basketball as my metric. Wikipedia states that an NBA basketball is 29.5 inches in circumfe…

### The Force is strong with this one...

Last night we were reviewing multiplication tables with Owen. The family fired off doublets of numbers and Owen confidently multiplied away. In the middle of the review Owen stopped and said, "I noticed something. 2 times 2 is 4. If you subtract 1 it's 3. That's equal to taking 2 and adding 1, and then taking 2 and subtracting 1, and multiplying. So 1 times 3 is 2 times 2 minus 1."

I have to admit, that I didn't quite get it at first. I asked him to repeat with another number and he did with six: "6 times 6 is 36. 36 minus 1 is 35. That's the same as 6-1 times 6+1, which is 35."

Ummmmm....wait. Huh? Lemme see...oh. OH! WOW! Owen figured out

x^2 - 1 = (x - 1) (x +1)

So $6 \times 8 = 7 \times 7 - 1 = (7-1) (7+1) = 48$. That's actually pretty handy!

You can see it in the image above. Look at the elements perpendicular to the diagonal. There's 48 bracketing 49, 35 bracketing 36, etc... After a bit more thought we…

### The Long Con

Hiding in Plain Sight

ESPN has a series of sports documentaries called 30 For 30. One of my favorites is called Broke which is about how professional athletes often make tens of millions of dollars in their careers yet retire with nothing. One of the major "leaks" turns out to be con artists, who lure athletes into elaborate real estate schemes or business ventures. This naturally raises the question: In a tightly-knit social structure that is a sports team, how can con artists operate so effectively and extensively? The answer is quite simple: very few people taken in by con artists ever tell anyone what happened. Thus, con artists can operate out in the open with little fear of consequences because they are shielded by the collective silence of their victims.
I can empathize with this. I've lost money in two different con schemes. One was when I was in college, and I received a phone call that I had won an all-expenses-paid trip to the Bahamas. All I needed to do was p…