Will You Live To See EM Pulse Scattering By Ships Nearing Light Speed?
We are all being asked to imagine what it will be like to see electromagnetic pulse scattering by spacecraft nearing light speed. Particularly by Timothy J. Garner, Akhlesh Lakhtakia, James K. Breakall and Craig F. Bohren in their new physics paper:
Humans will launch spacecraft that travel at an appreciable fraction of the speed of light. Spacecraft traffic will be tracked by radar. Scattering of pulsed electromagnetic fields by an object in uniform translational motion at relativistic speed may be computed using the frame-hopping technique. Pulse scattering depends strongly on the velocity, shape, orientation, and composition of the object. The peak magnitude of the backscattered signal varies by many orders of magnitude depending on whether the object is advancing toward or receding away from the source of the interrogating signal. The peak magnitude of the backscattered signal goes to zero as the object recedes from the observer at a velocity very closely approaching light speed, rendering the object invisible to the observer. The energy scattered by an object in motion may increase or decrease relative to the energy scattered by the same object at rest. Both the magnitude and sign of the change depend on the velocity of the object, as well as on its shape, orientation, and composition. In some cases, the change in total scattered energy is greatest when the object is moving transversely to the propagation direction of the interrogating signal, even though the Doppler effect is strongest when the motion is parallel or antiparallel to the propagation direction.
Electromagnetic Pulse Scattering by a Spacecraft Nearing Light Speed
Arthur C. Clarke not only asked us to imagine what it looks like when a craft nears light speed, he made an effort to describe it in his 1953 classic Childhood's End - behold the Stardrive:
...half a million kilometers away, the Stardrive went on. Up from the heart of the spreading moon-glow a tiny spark began to climb towards the zenith.
At first its movement was so slow that it could hardly be perceived, but second by second it was gaining speed. As it climbed it increased in brilliance, then suddenly faded from sight. A moment later it had reappeared, gaining speed and brightness. Waxing and waning with a peculiar rhythm, it ascended ever more swiftly into the sky, drawing a fluctuating line of light across the stars. Even if one did not know its real distance, the impression of speed was breathtaking: when one knew that the departing ship was somewhere beyond the moon, the mind reeled at the speeds and energies involved.
It was an unimportant by-product of those energies, Jan knew, that he was seeing now. The ship itself was invisible, already far ahead of that ascending light. As a high-flying jet may leave a vapour trail behind it, so the outward-bound vessel of the Overlords left its own peculiar wake. The generally accepted theory-and there seemed little doubt of its truth- was that the immense accelerations of the Stardrive caused a local distortion of space. What Jan was seeing, he knew, was nothing less than the light of distant stars, collected and focused into his eye wherever conditions were favorable along the track of the ship. It was a visible proof of relativity-the bending of light in the presence of a colossal gravitational field.
Scroll down for more stories in the same category. (Story submitted 12/11/2017)
Follow this kind of news @Technovelgy.
| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
you like to contribute a story tip?
Get the URL of the story, and the related sf author, and add
Comment/Join discussion ( 0 )
Related News Stories -
MIT Wants To Catch Interstellar Visitors
'INVESTIGATE MYSTERIOUS OBJECT ENTERING NEW CALEDONIA SYSTEM FROM NORMAL SPACE' - Niven and Pournelle, 1974.
Starlink Orbital Network Like Coruscant Traffic Jam
Vermin of the Sky? Or Internet access for all?
NASA Competition To Design A Bucket Drum For Moon Mining
'There was a heap of discarded ore where Grantline had carted and dumped it...' - Ray Cummings, 1930.
Are You Ready For Commercial Space Travel?
'It wasn't a pleasant trip; it was a miserable trip on a miserable, undersized tourist rocket...' - Pohl/Kornbluth, 1952.
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.
Sci-Fi Helps Young Readers Build Resiliency
'Reading science fiction and fantasy can help readers make sense of the world.'
I Want My 1928 Telestereo Hologram Now
'Instantly there appeared standing upon the disk, the image of a man...'
Memes Now Come From Neural Nets
'Your order said for him to be able to be able to work out twists on the gags in the file...'
Robot Dog Learns To Be Doggy From Real Dogs
'So we took pictures of Guzub making a Three Planets, and I could construct this one to do it exactly right down to the thousandth of a second.'
Unwanted Cruise Ships Huddle Together Out At Sea
'On the screen they passed in an endless, boundaryless flood of green specks...'
Sono Sion Electric Car Charges As You Drive
'It drew its power from six square yards of sunpower screens on its low curved roof.'
News Mood Filter Web Extension
'He adjusted the n, the r and b knobs, and hopefully anticipated a turn for the better...'
Fetal Lamb Rests In Artificial Womb
'... stewing warm on their cushion of peritoneum and gorged with blood-surrogate and hormones, the foetuses grew and grew...'
MIT Wants To Catch Interstellar Visitors
'INVESTIGATE MYSTERIOUS OBJECT ENTERING NEW CALEDONIA SYSTEM FROM NORMAL SPACE'
AutoX Sets Up Asia's Largest Robotaxi Center
'The robot cab seemed to know where it was going and, no doubt, the master machine from which it received its signals knew.'
E - Ink's Automatic Self Styling Color-Changing Dress
'The racks of gowns itched and quivered, their colors running into blurred pools.'
Soft Robots Use Kirigami Piezoelectric Sensor Skin
'A worthy opponent was the golem.'
Bosch Smartglasses Laser Paints AR Image On Your Retina
'Soon we'll be testing a system that projects directly on the retina of the eye.'
Maybe We Could Hibernate Until The Covid-19 Pandemic's End
'Cold-rest was a common last resort therapy for functional psychoses.'
Workplace Monitoring Hell, I Mean, Tool For Safe Distancing
'And here is the weirdest part -- I never see another employee the entire day.'
Patent Office Says AIs Cannot Be Inventors
'The real smart ones are as smart as the Turing heat is willing to let 'em get.'
More SF in the News Stories
More Beyond Technovelgy science news stories