Feeds

Tempel-1: iceberg or galactic rubber ball?

Deep Impact team ponders comet's composition

  • alert
  • submit to reddit

Beginner's guide to SSL certificates

April Fool special NASA's Deep Impact probe launched successfully on 12 January, on a mission to more accurately understand the properties of comets.

Its target is Tempel-1 - chosen because although it might be rock and ice like most other comets, scientists have reason to suspect that much of its structure is highly elastic frozen cross-linked hydrocarbons (very much like Kevlar or stiff rubber).

Ice can be a notoriously tough material, being resistant to both heat and shock, but scientists still don't know if the average comet has enough ice to be as tough as an iceberg or if it is as weak as the famous Shumacher-Levy comet which broke up under the influence of Jupiter's gravity. If, however, Tempel-1 is indeed comprised of rubber-like hydrocarbons, as mission planners suspect, then the results of the Deep Impact strike will be very interesting.

The plan is to hit Tempel-1 with a 370kg (~820lb) impactor (49 per cent copper) at 10km per second, releasing 19GJ of energy (around 4.8 tonnes of TNT) with a view to determining the comet's coefficient of elasticity by bouncing the impactor back into space and measuring its trajectory carefully with the following "mothership" and various Earth-based telescopes. Some scientists, though, are betting that the comet will simply shatter.

So much the better, say many experts. With our growing awareness of the risks of the Earth being struck by a rogue comet or meteor, understanding the physical properties of the comet has become a matter of the very survival of humanity. Just how hard must we hit a comet before it breaks up? Which technologies will work? Will we need to gently land on a shatter-proof comet and use rockets to nudge it onto a different course, or will nuclear weapons achieve the desired result?

Multiple interdisciplinary teams (geologists, physicists, computer programmers and statisticians) have been trying to determine the optimal conditions to strike the comet to achieve the best possible science.

To add a little spice to the mission, the teams are also running a competition to see who can most accurately predict - in the event of cometal disintegration - the paths of any pieces during the 1000 solar orbits after impact. Remnants over 50 metres in diameter which are captured by a planet (regarded as "potting" a comet) score 100 points each. If they succeed in getting the comet to spin rapidly and thus "screw back" using the solar wind to crash into Jupiter then that is worth 1000 points. Hitting the mothership with the projectile ("snookered") gains 5000 points.

There is, of course, the remote possibility that a substantial piece of Tempel-1 will eventually impact with Earth - a scenario chillingly described by scientists as "Pot Black". Said one cometologist: "We don't really want to think about that too much. We're just hoping that everything goes on cue..." ®

Related stories

Deep Impact en route to Tempel 1
Countdown to launch for Deep Impact
Boffins issue stealth comet apocalypse alert

Security for virtualized datacentres

More from The Register

next story
Boffins who stare at goats: I do believe they’re SHRINKING
Alpine chamois being squashed by global warming
Space exploration is just so lame. NEW APPS are mankind's future
We feel obliged to point out the headline statement is total, utter cobblers
Down-under record: Australian gets $140k for pussy
'Tiffany' closes deal - 'it's more common to offer your wife', says agent
Internet finally ready to replace answering machine cassette tape
It's a simple message and I'm leaving out the whistles and bells
FedEx helps deliver THOUSANDS of spam messages DIRECT to its Blighty customers
Don't worry Wilson, I'll do all the paddling. You just hang on
The iPAD launch BEFORE it happened: SPECULATIVE GUFF ahead of actual event
Nerve-shattering run-up to the pre-planned known event
Win a year’s supply of chocolate (no tech knowledge required)
Over £200 worth of the good stuff up for grabs
STONER SHEEP get the MUNCHIES after feasting on £4k worth of cannabis plants
Baaaaaa! Fanny's Farm's woolly flock is high, maaaaaan
Adorkable overshare of words like photobomb in this year's dictionaries
And hipsters are finally defined as self-loathing. Sort of
Not a loyal follower of @BritishMonarchy? You missed The QUEEN*'s first Tweet
Her Maj opens 'Information Age' at the Science Museum
prev story

Whitepapers

Choosing cloud Backup services
Demystify how you can address your data protection needs in your small- to medium-sized business and select the best online backup service to meet your needs.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.