Santa Cruz Good Times

Saturday
Jul 04th
Text size
  • Increase font size
  • Default font size
  • Decrease font size

How to Blow Up an Asteroid Heading Toward Earth

slug_asteroidImagine this: an asteroid is on a collision course with Earth. Not good. Now imagine that we’re able to blow it up, but it re-forms in, say, a few hours. Not good at all.

The latter is what Don Korycansky of the University of California, Santa Cruz, and Catherine Plesko of the Los Alamos National Laboratory in New Mexico discuss in their paper, “Re-aggregation times of potentially hazardous object fragments after a hazard mitigation impulse.”



According to the paper, many of the proposed techniques for changing the orbit of a potentially hazardous object (PHO), if one were to head our way, involve short-duration impulses such as stand-off blasts, surface detonations, and kinetic impacts. However, “such methods have the potential to knock fragments off the parent body… The resulting fragments may continue to threaten ground or orbital assets if they have not been dispersed far enough on diverging trajectories, or collectively deflected away from the original Earth-intercepting trajectory to a sufficient degree,” states the paper.

How long it would take the fragments to re-aggregate depends on the “physical properties of the original object and the impulse applied,” the paper continues. Korycansky and Plesko simulated blowing up asteroids one kilometer across with varying impulses to see how long it takes for the asteroids to put themselves back together. They presented the simulations at the Lunar and Planetary Science Conference in Houston, Texas earlier this month.

The results are a little alarming: when the fragments dispersed at a relatively low speed, it took only hours for the fragments to coalesce into a new rock. In other words, hitting an asteroid with a bomb that’s too small would cause the fragments to fly apart slowly, allowing them to re-clump under their mutual gravity – in two to 18 hours.

Not to fear, though. Other studies have shown that a 900 kiloton nuclear weapon (which is within our capability) is enough to blow up a one kilometer asteroid – and keep it blown up.
Comments (0)Add Comment

Write comment
smaller | bigger

busy
 

Share this on your social networks

Bookmark and Share

Share this

Bookmark and Share

 

The Boards Are Back in Town

More than a century after a famed trio of Hawaiian princes first surfed in Santa Cruz, their redwood olo surfboards are returning to the Museum of Art & History

 

We Hold These Truths to Be Self-Evident

Saturday, July 4, is the 239th birthday of the United States, commemorating the signing of the Declaration of Independence (the U.S. astrology chart has Aquarius moon—freedom for its people, by its people). Cancer, a liberating and initiating sign, is the “gate” where Spirit enters matter. Cancer receives and distributes Ray 3 (Divine Intelligence) and Ray 7 (new rules, new rhythms, new free nation under God). Cancer represents an intelligent freethinking humanity that can and must create right economics for the world. This means a policy of sharing, an opportunity for the U.S. when Venus (money, resources, possessions, etc.) retrogrades July and August in Leo (the heart of the matter). The United States has a unique spiritual task for the world: to lead humanity within and toward the light, accomplished by its people who must first awaken to this task, learn discrimination and be directed by the soul to assume the Herculean task of spiritual world leadership. Let us review the first words of our Constitution: “We the People of the United States, in order to form a more perfect Union, establish justice, ensure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity, do ordain and establish this constitution for the United States of America.” Let us form that union together. The following is a review of the spiritual tasks for each sign. Read all the signs. They all apply to everyone.  

 

The New Tech Nexus

Community leaders in science and technology unite to form web-based networking program

 

Film, Times & Events: Week of July 3

Santa Cruz area movie theaters >
Sign up for Good Times weekly newsletter
Get the latest news, events

RSS Feed Burner

 Subscribe in a reader

Latest Comments

 

Lunch is Packed

Picnic basket lunches from Your Place, plus smoked chili peppers, and new owners at Camellia Tea House

 

What would you like the Supreme Court to rule on next?

Raising the minimum wage so that those that are in poverty now can have a higher standard of life. Greanna Smith, Soquel, Nanny

 

Bruzzone Family Vineyards

Bruzzone Family Vineyards is a small operation run by Berna and John Bruzzone. Starting out a few years ago making only Chardonnay, they eventually planted Pinot Noir on their extensive property and now make this varietal as well.

 

Ty’s Eatery

Pop-up hooks up with Santa Cruz Food Lounge for healthy comfort food