Dialogue

'A colossal boondoggle'

I admire greatly the work of physicists and astronomers, and I appreciate investing in creative long-range, long-shot ventures. But the project described in "A Smashing Plan" [Idea, Spring] seems to me a colossal boondoggle.

Unless an asteroid a kilometer in diameter has the density of something akin to feathers, the largest space vehicle ever launched would have about as little effect on its path as would a mosquito on a charging elephant. Moreover, to have any beneficial effect, the intended impact would have to deflect the path of the asteroid in just the right direction; otherwise it would be useless—or even make the impending disaster worse.

I can see that if it occurs, the feared collision would "cause a global disaster." But isn't the probability of such an event in the next century, millennium, or many millennia exceedingly low—virtually zero? Is there any evidence of even one such collision in the 10,000 (or 20,000, or 50,000) years of human history?

There are dozens of ongoing global disasters affecting billions of people daily. Directing $150 million toward averting well-known current disasters would be less dramatic than the asteroid project but more humane.

Joe Morton, A&S '68 (PhD)
Towson, Maryland

Andy Cheng, chief scientist of the Applied Physics Laboratory's Space Department, responds:

The impact of a kilometer-sized asteroid would be a disaster on the scale of a global nuclear war and frightful to contemplate, but the average rate of such impacts is indeed quite low at a few per million years. However, we do not know when the next such impact will occur. And much smaller impacts occur much more frequently, while still being able to cause major damage, as witnessed by the impact of a ~20-meter body over Chelyabinsk, Russia, on February 15. The amount of deflection needed to avert a collision with Earth depends on the warning time—the longer in advance of a collision that a deflection is made, the smaller the amount of deflection needed.

The $150 million cost we estimate for the first asteroid mitigation experiment should be thought of like an insurance policy. The cost of this insurance at $150 million would be about 48 cents per person in the United States, one time—not enough to buy a candy bar in a vending machine. The cost of our mission will be less than the cost of making the movie Armageddon, which was $140 million in 1998 dollars or about $199 million today. The amount of money we spent to watch the movie was quite a bit more, over $500 million.

Keep swimming

Kudos on your feature story of JHU swimming ["Head First," Spring]! I am a 2009 biotechnology alum and, more importantly, a swimmer. I am so happy you focused on your swim team. They don't get enough attention. I love the line, "She moves a lot of water." This simple statement resonates with the very core of my being. I can't tell you how many times I've swum 1000s over stressful work times, personal times, or just to clear my head from the snow of Boston. What do you do when life gets you down? "Just keep swimming!"

Melissa Wojcik, A&S '09 (MS)
Boston, Massachusetts

Lost cause?

I enjoyed reading Bret McCabe's "From Farm to Plate to Policy" [Spring] on the agricultural challenge of feeding a world population expected to grow 40 percent over the next 40 years. However, I wish that the instructors at Johns Hopkins who are "tackling current and future food crises from a variety of angles" would consider one angle left out of this article: the curbing of global population growth through educating women and distributing contraception in the developing world. Unless population growth is kept under control, any cause may well be a lost cause.

Adam Potkay, A&S '86 (MA)
Williamsburg, Virginia

No place like home

I somewhat enjoyed the recent Spring edition of your publication. However, I spent the day thinking about a contradiction and an observation.

First, a contradiction. On page 11 [Dialogue], the effete weighed in on the negative impact that a horoscope section would have on your fine magazine with snobbish comments like, "An institution of higher learning shouldn't participate in mystic tripe like horoscopes." Yet on page 63 there is an ad for some Eastern gibberish from something called AndyO. I guess in today's politically correct world horoscopes are "mystic tripe" and Oriental mysticism is acceptable. I fail to see any difference.

Now on to an observation. I am tired of people coming to Maine in order to: find themselves, discover the meaning of life, reach nirvana, seek mental and emotional adventure, or cure depression. Susannah Hopkins Leisher's "Out of the Woods" essay is a typical heartbreak when she discovers that Maine did not cure all her problems when she returned to New Jersey. Maine was never anyone's idea of Walden and we would like to keep it that way. Come and enjoy the rugged beauty and people of Maine, but do not become disappointed when your troubles return when you return.

Dorothy discovered that she had responsibility for her own happiness and that, clicking her ruby slippers, there is no place like home!

Thomas J. Wilkinson Jr.
Swan's Island, Maine

Natural wonders

"Out of the Woods" [Spring] is a beautifully written commentary. Makes me thankful, once again, that I live in Maine. We are surrounded by the wonders of nature—spruce needles dappled with sun in the woodlands, crashing waves on the shore, brilliant red sunsets that fade to pink and gold, moonlight glimmering on the ocean, and bright stars in a black sky. Living close to nature makes us seem so small—and our troubles so insignificant. As Rachel Carson said, "Those who contemplate the beauty of the earth find reserves of strength that will endure as long as life lasts."

Helen Meserve
Newagen, Maine
Comment from hub.jhu.edu/magazine