Wow! Really?

Zero G Isn't Gravity free

2012-01-27T05:49:00.000-08:00

Watch a Space Shuttle launch and you'll hear about "zero gravity" and "zero G", terms that make people think (incorrectly) that someone or something in orbit has somehow escaped Earth's gravity. Not so. Without gravity you couldn't put a spacecraft in orbit.

Imagine hitting a baseball across a ballfield. Picture the arc it makes as it goes off into the outfield. To hit a home run, you have to hit it higher, and harder, to make a bigger arc that takes it out over the fence.

Now imagine launching the ball using a catapult, a cannon, or rocket. As you send it with more force, the ball arcs out higher and faster, and lands farther and farther away--across the street, out of the neighborhood, over your town, across your country, even across the nearest ocean.

Eventually, if you launch it high enough and hard enough it will sail right over the distant curving edge of the earth itself. Instead of coming down, it literally misses the ground and loops around our planet. It constantly falling and missing, falling and missing, falling and missing.

Now, if you think about it, you'll understand why low orbits have to be faster and high orbits have to be slower. Now you know why geostationary satellites aren't stationary at all, but moving in an orbit at the same speed the Earth rotates.

Next time you see a rocket launch think about hitting a baseball hard enough for it to fly right along side the spacecraft, and you'll have a good idea why, except for gravity, the rocket and your ball would go straight out into space, never to be seen again.

What Doesn't Kill Us Makes Us Stronger?

2009-08-08T13:49:00.000-07:00

Philosopher Friedrich Nietzsche, in Twilight of the Idols (1888) wrote "What does not destroy me, makes me stronger." But modern research by the Naval Health Research Center shows that's not the case. If you've been assaulted, you're twice as likely to suffer from post traumatic stress syndrome.

Data on exposures and health outcomes were collected as part of the Millennium Cohort Study. Of 55,000 participants, data was anaylzed from from 5324 (881 women and 4443 men) who were in combat in Iraq and Afghanistan and had no Post-traumatic Stress Syndrome (PTSD) symptoms before they went.

As reported in the journal Epidemiology, more than twice as many man and women who had been assaulted prior to entering combat suffered from PTSD afterwards than those who had never been assaulted.

In other words, the odds of new-onset PTSD symptoms was more than 2-fold higher in both women and men who reported assault prior to deployment.

Alcohol Abuse Is No Laughing Matter

2009-08-08T13:05:00.000-07:00

The returning vet who's become a drunk is a recurring, if sad, stereotype. But until recently there wasn't much data on the problem.

Late last year the Naval Health Research Center published a report in the Journal of the American Medical Association that shows the problem is not a myth.

Data from the Millennium Cohort Study showed that Reserve and National Guard personnel and younger service members who deploy with reported combat exposures are, in fact, at increased risk of new-onset heavy weekly drinking, binge drinking, and alcohol-related problems.