Tiny dust particles in the solar system

Sep 09, 2013
Zodiacal light scattered from dust grains in our solar system is seen rising diagonally up to the left in this image, as the plane of the Milky Way rises up to the right. Scientists have used the STEREO spacecraft to study tiny nanodust particles in the solar system. Credit: Tunc Tezel, TWAN; APOD

(Phys.org) —In our solar system, dust particles are abundant, created by asteroid collisions and by the evaporation of comets. These particles are the source of the zodiacal light, a diffuse glow in the night sky that extends along the ecliptic (the plane of the solar system) and which is seen from Earth stretching along the zodiac, most easily after sunset or before sunrise. It is so faint that moonlight is enough to mask it.

The gravity of the planets affects the distribution of these . The Earth, for example, collects dust in a series of patches which lie in a ring along the Earth's . New measurements used radio instruments on twin interplanetary spacecraft to study nanometer-scale dust particles, or "nanodust." A grain of nanodust is smaller than a wavelength of , and unlike the roughly ten times larger grains responsible for the , nanodust is too small to efficiently scatter sunlight and can only be detected using space instruments. When a grain of nanodust impacts a spacecraft, it creates an expanding cloud of ionized gas which can lead to a voltage pulse between a spacecraft's body and its antenna, and which can then be sensed. Nanodust can be accelerated by the interplanetary magnetic field to the speed of the solar wind—significantly faster than the orbital speeds of heavier . Because the electrical signal induced by a dust grain depends more strongly on its impact speed than on its mass, nanodust produces a strong signal despite its being lightweight.

CfA astronomers Gaetan Le Chat and Justin Kasper, along with eight colleagues, used the Low Frequency Receiver onboard the twin Solar TErrestrial RElations Observatory (STEREO) spacecraft in an extensive program spanning seven years to deduce the characteristics of nanodust. The two STEREO spacecraft are in solar orbits with one ahead of the Earth and one trailing behind. On average, the spacecraft recorded about fifty nanodust impacts (voltage pulses) every second, with occasional bursts of up to a thousand hits. The scientists analyzed over seven hundred thousands measurements to conclude that nanodust is a significant contributor to the total mass of material in interplanetary space, in agreement with earlier estimates, and to begin to characterize its properties. Although STEREO was designed to study solar storms, not nanodust, the new results not only help complete the picture of our solar system, they show how innovative scientists can sometimes squeeze added science from workhorse instruments.

Explore further: Amazing raw Cassini images from this week

More information: Le Chat, G. et al. Interplanetary Nanodust Detection by the Solar Terrestrial Relations Observatory/WAVES Low Frequency Receiver, Solar Physics, 286, 549, 2013.

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User comments : 4

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cantdrive85
1 / 5 (11) Sep 09, 2013
It is that electrodynamic nanodust which holds the universe together. No DM necessary, just an electrodynamic skeleton of self assembling nanodust produced by plasma arc discharge.
cantdrive85
1 / 5 (11) Sep 09, 2013
hemitite
not rated yet Sep 09, 2013
I'm impressed!
cantdrive85
1 / 5 (8) Sep 09, 2013
If it would be charged, it would explode into infinity.

I guess if you say so, fortunately you don't have a clue as to which you are speaking nor did you read the attached paper. Waving bunnies is infinitely more stupid than electrodynamic nanodust which we know for a fact exists.

http://uni-skelet...main.htm