NASA - National Aeronautics and Space Administration

TITLE:

NASA's Space Solar Power Project: Plant Response To Microwave Radiation

PREPARED FOR:

NASA's Space Solar Power Program

WRITER:

Jay Skiles, NASA Ames Research Center

PRODUCER:

DATE:

May 3, 2002

26. misc. vegetation in park, different from 25 above

**condensed plant-response video starts here**

Not much is known about how plants, animals and humans will respond to continuos microwave exposure.

27. graphic

PURPOSE OF EXPERIMENT

Our experiment will show how an important plant species will respond to continuous exposure to microwaves.

28. graphic

NO DIFFERENCE

CONTROL AND TEST PLANTS

Our hypothesis is that plants exposed to microwaves will be no different from those plants that are not exposed to microwaves.

29. graphic

person talking on cell phone

The microwaves are generated by a device something like that in your cell phone.

30. shot of VCO un-mounted with quarter for scale

This microwave generation device is called a voltage-control crystal oscillator or "V C O".

31. shot of mounted VCO

Microwaves, at 2.45 Gigahertz and at 1 to 10 milli-watts per square centimeter intensity, are generated in the oscillator . . . (beat)

32. shot of cable w/sma
connectors

pass through a short cable . . . (beat)

33. shot of emitter horn

and are broadcast over the growing plants by the antenna or emitter horn.

34. shot of reflector from emitter horn POV

The microwaves are then bounced off the adjustable reflector . . . (beat)

35. view of large tray in lab where plants are growing

thus exposing the TEST PLANTS to the microwaves.

36. view of the tray from the reflector POV

Note that the plants growing behind the metal sheet or shield, the CONTROL PLANTS, do not receive any microwave exposure.

37. view of entire experimental setup

The experiment is designed so that the only variable to which the plants are subjected is microwave exposure.

38. graphic

PLANTS

A plant representative of important agronomic species is alfalfa.

39. person lugging bag of potting mix to lab from storage area

The plants are grown in a potting mix in plastic pots.

40. shot of pots filled w/ soil

A measured amount of soil is placed in each pot.

41. person weighing seeds

A measured amount of alfalfa seed is placed in each pot.

42. person using surgical tubing to water the plants in the growth tray

And the soil is moistened.

43. several frames of the light rack showing florescent tubes and light bulbs

The light necessary for photosynthesis is supplied by an overhead rack of fluorescent tubes and several incandescent light bulbs.

44. person in lab coat bending over the plants

To test the hypothesis, precise measurements are taken of the control and experimental plants.

45. person in lab coat using the portable gas exchange LDC4 device

Variables measured include gas exchange.

46. person using the SPAD meter

Another variable is leaf chlorophyll concentration.

47. person taking measurements of plants

Also measured are gross plant variables such as stem length, internodal distance, and overall vigor.

48. person watering plants; outside shot, park

These experiments are ongoing and will be expanded to include mixes of plants and growth of plants from seeds whose pro-gen-I-tors were exposed to this same level of microwave frequency and intensity.

49. outside shot, park (different from 48 above)

These studies will help determine whether plants can grow in an environment of sustained microwave illumination.