Archive for the ‘Sunlight’ Tag

Inexorable–Stealing Away the Last of the Sunlight   19 comments

Inexorable – Stealing Away the Last of the Sunlight

Monochrome Moon Wolves

 

Monochrome Moon WolvesSpacePort Eclipse Wolves

Monochrome moon wolves! A subtle, relentless shadow crept across the face of an alien sun sending a soft, fiery glow sliding across the abandoned landing unit tips where only the moon wolves resided and the wild vegetation flourished growing rapidly in the cracks and crevices of the deserted buildings, long since abandoned by their alien civilizations. The abandoned shuttle port and its overgrown, unused space crafts roamed only by the Wolves_Abandoned SpacePort glowing moon wolves sliding subtly amongst the empty shells, food in plentiful supply around the crumbling, rusted hulls and skeleton cruisers.

 

 

Inexorably the eclipse light silenced them, cooling the air as the light faded into eerie, unnatural night, changing the atmosphere into something apocalyptic and alien to the moon wolves drawn back to the higher ground on the rooftop. Gradually stealing away the last of the sunlight till only the corona remained – a glowing fire burning flames and solar flares bursting across the darkened skies… The moon wolves watched with heads thrown high to the solar winds as darkness descended and the world feel silent. The eerie howl of the wolf song echoed on… and on through the monochrome eclipse light.

Wolves_Abandoned Rooftops

Eclipse Light WolvesInexorable_Spaceport Eclipse Wolves

Inexorable_Stealing Away the Last of the Sunlight

Solar Sails   14 comments

Solar Sail Space Crafts

 

Space craft propelled directly by the power of sunlight (solar cells are indirect power).

clip_image002

Two projects are set for launch this year:-

  •   IKAROS – launched by Japanese Space Agency JAXA
  •   SOLARSAIL-1 by US based Planetary Society

(These are demonstrations to show that it can work, but they are very tiny!)

Solar Sail Craft Basics

gossamer_solar_sail

Constructed from Gossamer – thin reflective sails capture photons

  •   Photons are packets of energy that make up sunlight

The sails gain momentum from the photons as they are reflected from their surface. Energy gained pushed the craft forwards gently. The force of sunlight is very little but this is fine as their CO2 acts against it in the vacuum of space.

Future sails could be made of nanotube mesh – 30 times lighter, and could increase acceleration dramatically.

nanotube_mesh

Travel and Speeds

With the Sun set to shine for a good billion years or so yet, it can be considered an endless fuel supply therefore a Solar Sail Craft could in theory, reach speeds of hundreds of kilometres per hour making travel to Pluto a mere three years and to the outer limits of the Solar System years rather than decades. NASA’s Voyager craft took thirty years to reach these limits. A Solar Sail Craft launched today would pass it in ten years.

                                               voyager_1 voyager_2

Other Solar Sails

They would need sails 100m across and a boost from a large and unrealistically expansive laser system as the Sun’s energy decreases with distance. However laser-boosted systems could see a Solar Sail Craft travelling at speeds of up to 20% speed of light (60,000km/hr or 45,000mph) every second. This would make visiting neighbouring stars in our lifetime our best possibility.

Brief History

  1. Concept first proposed by German astronomer Johannes Kelper in seventeenth century
  2. 1862 Scottish physicist James Clark Maxwell discovers that light exerts a pressure on a surface.
  3. 1867 Jules Vernes suggests light pressure could provide a mechanical means of propulsion.

solarsail4. 1924 Russian scientist Fridrickh Arturovich Tsander wrote “For flight in Interplanetary Space I am working on the idea of flying using tremendous mirrors of very thin sheets capable of achieving favourable results.“

Mariner Probe

5. 1971 When NASA’s probe Mariner ran low on steering thrusters fuel en route to Venus engineers angled its solar panels into the Sun and used solar radiation pressure to steer it back on course.

Cosmos-1

6. 2005 Cosmos-1 a Solar Sail designed by US Planetary Society failed its test, due to rocket failure on launch vehicle, resulting in it being unable to reach its intended orbit.

                                                                         Nanosail-DNanosail-D_(2)

7. 2008 NASA’s Nanosail-D mission, to test the Solar Sail’s deployment techniques. Lost during launch failure.