Science Fiction
Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 |
Could Ground-Based Lasers De-Orbit Space Junk?
An interesting paper was recently published proposing to use ground-based high-intensity pulsed lasers to bring down small objects in low Earth orbit.
Among the approaches to the proposed mitigation and remediation of the space debris problem is the de-orbiting of objects in low Earth orbit through irradiation by ground-based high-intensity pulsed lasers. Laser ablation of a thin surface layer causes target recoil, resulting in the depletion of orbital angular momentum and accelerated atmospheric re-entry. However, both the magnitude and direction of the recoil are shape dependent, a feature of the laser-based remediation concept that has received little attention. Since the development of a predictive capability is desirable, we have investigated the dynamical response to ablation of objects comprising a variety of shapes. We derive and demonstrate a simple analytical technique for calculating the ablation-driven transfer of linear momentum, emphasizing cases for which the recoil is not exclusively parallel to the incident beam. For the purposes of comparison and contrast, we examine one case of momentum transfer in the low-intensity regime, where photon pressure is the dominant momentum transfer mechanism, showing that shape and orientation effects influence the target response in a similar, but not identical, manner. We address the related problem of target spin and, by way of a few simple examples, show how ablation can alter the spin state of a target, which often has a pronounced effect on the recoil dynamics.
(Bringing down space junk [pdf])
Geometry used to estimate the velocity change required to obtain a pre- determined perigee via the initial stage of a Hohmann transfer (scales exaggerated for clarity). Starting from a counter-clockwise circular orbit (solid curve) with radius r, an impulse opposite the velocity vector, resulting in a velocity change v, is applied at the transfer point. The perturbed orbit (elliptical until capture; dashed curve) is characterized by its semi-major axis a and perigee rp, where rp is suciently low for re-entry to occur.
SF great Arthur C. Clarke had a similar idea, but he wanted to use lasers to blast them from orbit with appropriately equipped ships.
In his 1978 novel The Fountains of Paradise, Arthur C. Clarke uses Operation Cleanup to make sure that low earth orbit is clear of debris for the newly constructed space elevator.
Fortunately, the old orbital forts were superbly equipped for this task. Their radars - designed to locate oncoming missles at extreme ranges with no advance warning - could easily pinpoint the debris of the early Space Age. Then their lasers vaporized the smaller satellites, while the larger ones were nudged into higher and harmless orbits.
From Pulsed Laser Interactions with Space Debris: Target Shape E ects.
Scroll down for more stories in the same category. (Story submitted 5/18/2013)
Follow this kind of news @Technovelgy.| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
Would
you like to contribute a story tip?
It's easy:
Get the URL of the story, and the related sf author, and add
it here.
Comment/Join discussion ( 2 )
Related News Stories - (" Space Tech ")
SpaceX's Starman Tesla Roadster In Space
'Somewhere in space, a chrome and blue automobile raced the green light of Earth.' - Theodore Sturgeon, 1941.
Warp Drive Tech Back On The Menu
'Detailed plans for the construction of the Gundstetter-Halone warp drive were flowing.' - RM Williams, 1940.
JAXA Int Ball 2 Coming Right Along As Star Wars Remote
'Hocus-pocus religions and archaic weapons are no substitute for a good blaster at your side.' George Lucas, 1976.
Space Traffic Management (STM) Needed Now
'...the spot was a lonely one in an uncharted region, far from the normal lanes of space traffic.' - Arthur William Bernal (1935)
Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.
Science Fiction
Timeline
1600-1899
1900-1939
1940's 1950's
1960's 1970's
1980's 1990's
2000's 2010's
Current News
Nuclear Plant Restarted To Power AI To Feed Us Dreams
'...Anything was possible in my imaginary environment.'
SpaceX's Starman Tesla Roadster In Space
'Somewhere in space, a chrome and blue automobile raced the green light of Earth.'
Pivotal Blackfly Electric Aircraft Lifts And Hovers
'That explains how it was so easy for me to remain motionless in midair...'
CORLEO Robotic Horse Concept Looks Ready To Ride
Imagine digging your heels in to a steam horse!
Who First Thought Of A Tin Foil Hat?
'We had discovered that metal was relatively impervious to the telepathic effect.'
Warp Drive Tech Back On The Menu
'Detailed plans for the construction of the Gundstetter-Halone warp drive were flowing.'
Huawei Pura X Folding Phattie Phone
Why can't we get more innovative phone configurations?
Sleep Pods At Daxing International Airport
'Do not waste your priceless company on the unappreciative folds of a sleep pod...'
Robot Baristas Learn Their Trade Without Paying Royalties
'...so we've promised him a generous pension from the royalties.'
JAXA Int Ball 2 Coming Right Along As Star Wars Remote
'Hocus-pocus religions and archaic weapons are no substitute for a good blaster at your side.'
Robot Bricklayer Or Passer-By Bricklayer?
'Oscar picked up a trowel. 'I'm the tool for the mortar,' the little trowel squeaked cheerfully.'
Robot Gas Station Attendant Pumps Gas For You
'... he waited for the robotrix attendant to finish fueling up his ship.'
Engineer Creates Crazy Motorized Track Hospital Bed
The Roujin Z system provides care to fully bedridden patients - and then some!
Tiny Flying Robot Weighs Just One Gram
'Aerostat meant anything that hung in the air. This was an easy trick to pull off nowadays.'
Some Ringworld Configurations Are Stable
'The Ringworld had no horizon. There was no line where the land curved away from the sky.'
TRANSFORM Dynamic Furniture Concept Becomes What You Need
'An adjustment panel outside the door would cause it to extrude various appurtenances in memory plastic...'
