Even Bruce Willis couldn’t save Earth from an asteroid

By Mark Waghorn via SWNS

Bruce Willis might have saved the earth by blowing up an asteroid in the hit film Armageddon but in reality, his heroics would have been useless, according to scientists.

An asteroid hurtling towards Earth would be indestructible due to its shock-absorbent nature, a study of asteroid rock has shown.

The analysis of specks of dust from peanut-shaped space rock Itokawa found it is resistant to collision - and impossible to smash.

The 500-meter-long "pile of rubble" is 1,250,000 miles away - and as big as Sydney Harbour Bridge.

Lead author Professor Fred Jourdan, a planetary scientist at Curtin University, said: "The huge impact that destroyed Itokawa's monolithic parent asteroid and formed Itokawa happened at least 4.2 billion years ago.

"Such an astonishingly long survival time for an asteroid the size of Itokawa is attributed to the shock-absorbent nature of rubble pile material.

"In short, we found Itokawa is like a giant space cushion - and very hard to destroy."

In the 1999 film oil rig workers are hired by NASA to drill into a Texas-sized asteroid and detonate a nuclear bomb to break it into pieces.

The study in Proceedings of the National Academy of Sciences shows it wouldn't work.

It also suggests the chances of another asteroid wiping out life should be considered more of an existential threat than feared.

The Australian team used two scanning techniques that dated meteor impacts and measured the shock.

Durability was previously unknown - jeopardizing the design of defense strategies.

Co-author Prof Nick Timms said: "We set out to answer whether rubble pile asteroids are resistant to being shocked or whether they fragment at the slightest knock.

"Now we have found they can survive in the solar system for almost its entire history, they must be more abundant in the asteroid belt than thought.

"So there is more chance that if a big asteroid is hurtling toward Earth it will be a rubble pile."

It turns out Itokawa is almost as old as the solar system itself.

The results could be key to saving the planet from a strike similar to the one that wiped out the dinosaurs.

Prof Jourdan said: "Unlike monolithic asteroids, Itokawa is not a single lump of rock but belongs to the rubble pile family which means it's entirely made of loose boulders and rocks - with almost half of it being empty space.

"The survival time of monolithic asteroids the size of Itokawa is predicted to be only several hundreds of thousands of years in the asteroid belt."

A six-mile-wide space rock struck Earth 65 million years ago - carving out a massive crater in the Gulf of Mexico.

The impact caused catastrophic conditions including thick clouds of dust and ash that caused global temperatures to plummet - killing off most animal species.

Prof Timms said: "The good news is we can also use this information to our advantage.

"If an asteroid is detected too late for a kinetic push, we can then potentially use a more aggressive approach like using the shockwave of a close-by nuclear blast to push a rubble-pile asteroid off course without destroying it."

The samples were returned to Earth from Itokawa by the Japan Aerospace Exploration Agency (JAXA) as part of its first Hayabusa mission in 2010.