20 Silicon chip Australia’s electronics magazine siliconchip.com.au
Fig.12: a photo of the Starfish Prime nuclear
explosion (400km altitude) taken 45-90
seconds after detonation in 1962. It caused an
unexpectedly strong electromagnetic pulse which
destroyed several satellites and land-based
electrical devices.
plication are the Vorago RH-OBC-1,
designed for CubeSats (Fig.10), and
the Ramon GR712RC (Fig.11
Notable radiation-induced
events
Some notable events due to radia-
tion interacting with electrical ap-
paratus or electronics are as follows:
- Geomagnetic storm, 1859: A geo-
magnetic storm (also known as a solar
storm) occurred on 1st & 2nd Septem-
ber 1859. This resulted in numerous
sunspots and solar flares.
What is assumed to be today a cor-
onal mass ejection (the expulsion of
charged particles from the
sun) then resulted in in-
duced currents in telegraph
wires, which caused shocks
to operators and also start-
ed some fires.
This storm was also
known as the “Carrington
Event”.
The Aurora was seen as
far north as Queensland.
The original 1859 More-
ton Bay Courier newspaper
article about the aurora can
be seen at: siliconchip.com.
au/link/aaq4- The Starfish Prime
nuclear test: In 1962, the
United States conducted
high-altitude nuclear tests,
detonating a 1.4 megatonne
nuclear warhead 400km
above the Pacific Ocean, 1450km from
Hawaii (see Fig.12).
The explosion caused an unexpect-
edly large electromagnetic pulse, re-
sulting in electrical damage in Hawaii,
destroying 300 street lights, setting off
burglar alarms and destroying a mi-
crowave link.
Bright auroras were also observed
in the detonation area and in an area
on the opposite side of the Earth from
the detonation area.
Apart from the electromagnetic
pulse, the explosion also produced
beta particles (electrons) which per-
sisted as an artificial radiation belt
within the earth’s magnetic field un-
til the early 1970s.
The failure of many satellites was
attributed to the energetic electrons
injected into the Earth’s magnetic field
by this detonation.
These satellites included Ariel,
TRAAC and Transit 4B, while the first
commercial communications satel-
lite (Telstar) was damaged, ultimately
leading to its complete failure in 1963.
The Russian Kosmos V satellite was
also damaged, among others.
A video about the Starfish prime
explosion titled “Operation Dominic
I and II - Starfish Prime Part 2 1962”
can be seen at: siliconchip.com.au/
link/aaq5- Radioactive decay in electron-
ics chip packaging: Errors from trace
radioactive materials in electronics
chip packaging and silicon came to
be recognised as a significant prob-
lem in the 1970s.
Alpha particles (helium nuclei) are
a common result of radioactive decay
but are sufficiently slow and massive
that they generally cannot penetrate
the housing of electronics (they are
even stopped by clothing or a sheet
of paper).
However, alpha particles originat-
ing from that packaging itself can in-
terface with and affect the electron-
ics within.
A very low alpha particle flux of
0.001 counts/hr/cm^2 are required to
minimise the problem. This is be-
Videos on radiation hardening of
electronics
“Demonstration of the effects of radiation
on a commercial video camera”: https://you-
tu.be/5kE0Rsf9W_I
* “Watch A GoPro Travel Through Extreme
Radiation”: https://youtu.be/QZZR4DJLdfM
* “Declassified U.S. Nuclear Test Film
#62”: https://youtu.be/KZoic9vg1fw (from
1962, a video about the effects of high alti-
tude nuclear detonations)Spacecraft operators and operators of certain
other sensitive equipment are concerned with
anomalies caused to electronics by radiation.
Radiation from space comes under the aus-
pices of “space weather”, and several websites
have been established where information on con-
ditions can be obtained.
Some such websites, including one from the
Australian Government, are as follows:
http://www.sws.bom.gov.au/Space_Weather
http://www.spaceweather.com/
http://www.swpc.noaa.gov/
http://www.swpc.noaa.gov/products/seaesrtFig.13 at right shows an example of space
weather data taken from the NOAA Spacecraft
Environmental Anomalies Expert System –
Real Time (SEAESRT). Fig.13: space weather is relevant to spacecraft operation. This screen grab
shows a space weather readout from the NOAA website, for a satellite in
geostationary orbit at 270°E.Finding out about “space weather”