Saturday, July 22, 2006

“NASA’s Goals Delete Mention of
Home Planet”

“From 2002 until this year, NASA’s mission statement…read:

“ ‘To understand and protect our home planet; to explore the universe and search for life; to inspire the next generation of explorers…’

“In early February [2006], the statement was quietly altered, with the phrase ‘to understand and protect our home planet’ deleted…

“[The] change comes as an unwelcome surprise to many NASA scientists, who say the ‘understand and protect’ phrase was not merely window dressing but actively influenced the shaping and execution of research priorities…

“[The] National Aeronautics and Space Act established the agency in 1958 [and had as its] first objective…‘the expansion of human knowledge of the earth and of phenomena in the atmosphere and space.’ ”
“The ‘understand and protect’ phrase was cited repeatedly by James E. Hansen, a climate scientist at NASA who said publicly last winter that he was being threatened by political appointees for speaking out about the dangers posed by greenhouse gas emissions.”
One has to wonder: if NASA is not the lead agency to address global threats to our continued existence, who is? Why would space exploration be more important than working to ensure the continuation of life, especially human life, on Earth?


your children well

their father’s hell

did slowly go by…
(lyrics: Graham Nash; photo: Sebastian Scheiner/AP)

Friday, July 21, 2006

Hard work

(photographer unknown)

Angela Merkel, Chancellor of Germany, in Science (14 July 2006):
“ ‘People love chopping wood,’ Albert Einstein once said. ‘In this activity one immediately sees results.’

“Science policy, by contrast—like science itself—demands staying power. It requires cooperation between many different actors, the investment of considerable resources, and the courage to strike out in new directions.”
Like so many other things in life, too.

Wednesday, July 05, 2006

How I spent Independence Day

I detest fireworks - for their noise and pollution and dangers, and nearly all recent news has been depressing beyond belief, so while nearly everyone has forgotten nearly everything that Independence Day represents, I decided to ignore it, and instead celebrate some of my favorite things, beginning with the mechanical arts manifested in that thing of beauty and wonder of wonders, the steam-driven train......

That the Redwood Valley Railway still gives joy and delight to children is merely icing on the cake.

“Oak” - a 2-6-2 Prairie-class engine

Scale: 5/12 narrow
Gauge: 15"
Fuel: Oil
Boiler pressure: 175 psi
Drivers: 14"
Truck wheels: 10"
Tractive effort: 975 lbs.
Gross wt: 5 tons

Data from: “Redwood Valley Railway - A Brief History and Technical Specification of the Tilden Park Steam Trains”

Tuesday, July 04, 2006

In all probability

In a June 27 letter to the Science section of The New York Times, Bruce Mansbridge (psychologist and assistant clinical professor at the University of Texas) writes:
“In a classic game-show puzzle, a contestant picks one of three doors; the host, who knows where the prize is, then opens another door to show no prize, and asks the contestant if he would like to switch his choice to the other closed door. Few switch, even though that would double the odds of winning.”

Let’s say you are a game show contestant, and you are presented with three doors, one of which hides a prize. You can choose blue, red, or green, and you choose blue, giving you one chance out of three to win.

Now the host opens the green door, revealing the absence of a prize, and offers you the chance to choose a different door. How does this change your odds of winning?

Effectively, you now have two choices, with a prize behind one of them. You can keep your blue choice, or shift to red. Thus, you now have a completely new choice, of two doors with a prize behind one of them, or one chance out of two to win. Your odds of winning have gone up, from one-third to one-half, an increase of one-sixth. Note that it is not possible to view this choice as a two-thirds probability, no matter whether you change your choice or not.

Given that you did not choose green at the beginning, and that the contest now has entirely different starting conditions, do you double your odds of winning by taking the host up on his offer and changing your choice to red, as claimed by Dr. Mansbridge? No, you do not. Whether you change from blue to red, or not, you still have a 50% chance of winning, because you have just two doors to choose from. There is no way that this can give you a two-thirds chance to win:

The fallacy in Dr. Mansbridge’s claim comes from not understanding that once the empty green door has been revealed, the contest begins anew, and the third door is now irrelevant. You only have two doors, and you have just one containing a prize. Nothing that has gone before has any bearing whatsoever on your choice.

Photo credits: edouardo and bowlingranny