Flying satellites in space might seem like a real stretch
for the amateur. In fact, for decades the amateur
radio community has been building and flying their
series of amateur satellites under the guidance of AMSAT
(The Radio Amateur Satellite Corporation)
Furthermore, amsats have been first in a number
of satellite technologies including store and forward
messaging and dopplar location for search
and rescue. See Highlights
of Space Radio for more examples of amsat
accomplishments.
Amsats have also become the models for the smallsat
revolution. More and more spacecraft, such as the space
probes Lunar Prospector
and the Mars
Global Surveyor, as well as low earth orbit comsats
like Orbcomm,
are built small and specialised and in relatively short
times. This goes against the traditional approach of
huge general purpose spacecraft (see, for example, the
Cassini
probe to Saturn) that take many years to build.
Today there are dozens of university student
groups around the world building micro (10-50kg) and
nano (1-10kg) satellites for scientific research and
as technology demonstrators. These satellites provide
tremendous educational opportunities for the students.
The key to the success of amsats and student
satellites is obtaining a cheap ride to orbit.
This usually is provided by the piggyback ride.
This technique was pioneered by the Amsat community.
Small satellites can ride piggyback because most rockets
provide excess thrust for the mass of a typical satellite
and for its desired orbit. So dead weight ballast
is added. The OSCAR I group convinced the Air Force
in 1961 to carry OSCAR I instead of this ballast
for one of its Discovery satellite launches. A release
mechanism freed the craft once the final stage reaches
the proper orbit.
Some satellites have been released by the shuttle.
The French and Russian student-built Spoutnik,
a working replica of the original, was actually hand
launched by Cosmonauts on Mir.
The spacecraft will use the same structure as
AO-40 (formerly Phase 3-D) that was launched into
earth orbit in the fall of 2000.
The document P5A-to-Mars!(712k
pdf) describes the technical challenges and solutions
for such an ambitious mission. It also mentions the
possibilities of a sub-satellite that could be released
once the spacecraft reaches Mars orbit. The German
Mars Society has proposed a craft that would release
a balloon
that would provide measurements of the Mars atmosphere.
Like AO-40, the Mars probe will piggyback on an Ariane
5 launch and use the same 400 N propulsion system. (We
expect they will solve the problem that caused the that
nearly destroyed the AO-40 and prevented it from reaching
the desired highly elliptical orbit.)
The Phase 3-E
project was also approved that will test in earth orbit
various techniques and technologies for the Mars mission.
AO-40 cost about $4 million that was raised from AMSAT,
ham radio operators, and other sources. The Mars probe
will cost more than this and will required that get
considerable outside contributions.
Phase 3-E
This is a follow-on mission to A0-40 ( Phase 3-D before
launch, see below)
and also a precurser to the Mars P5-A mission mentioned
above. It will be launched as a "communication
and scientific platform into a highly elliptical orbit
around Earth."
An engine misfiring early in the AO-40 mission prevented
it from meeting many of its objectives, including the
placement into a large elliptical orbit that would provide
long periods of visibility to amateur ground stations
in the northern hemisphere. Several transmitters on
AO-40 also failed to work.
P3-E will attempt to correct these problems. It will
"serve as communication platform for the nearly
2 million radio amateurs worldwide. They constitute
a network for further exploration of the so called 'uncoordinated
multiple access', to provide simultaneous and freely
available service to a large number of groundstations."
It will also serve as a test platform for the Mars
P5-A spacecraft.
Towards
P3E, (pdf , 955k) describes the P3-E project and
also reviews the accomplishments and failures of AO-40.
AO-40
(Phase 3D) Project
A0-40 ( Phase 3-D before launch) is the most ambitious
amateur satellite built and launched so far and cost
about $4.5
million.
The satellite will travel on a large elliptical
orbit that will make it visible for long periods
to North American, Europe and Asia.
It will have much higher power and sensitivity
than previous Amsats, allowing for cheaper, simpler
ground stations.
Microwave transponders brings new capabilities
and opportunities.
Launched on Nov.15, 2000, there were several problems
during the first month after launch. The satellite,
in fact, went completely silent for two weeks and was
feared lost. But eventually contact was restored.
Gradually more systems have been activated and the
perigee lifted to over 800km using an amonia gas system
intended for station keeping.
IDFIX France AMSAT
France recently launched the two IDEFIX amateur
picosats. The amateur radio transmitters are attached
to the third station booster of the Ariane rocket that
launched the Spot 5 main payload. The battery powered
transmitters will remain in orbit for about 40 days.
The SATEDU nanosat
is being developed by students.
SATEDU - 20kg
microsat project developed by students.
STENSAT
Amateur Radio Picosatellite Stensat is a small (12 cubic inch, 0.5 kg) satellite
for use by amateur radio operators world wide with
a single channel mode "J" FM voice repeater. Stensat
was developed by amateur enthusiasts in the Washington
DC area and will be installed as part of Stanford
University's OPAL
Picosatellite project. The projected launch date is
September 15, 1999 from Vandenburg AFB. SpaceNews
article.
Houston Amsat Network
Listen to this weekly online broadcast for the latest
on Amsat developments. See also the w0kie
lists of other satellite related internet spacecasts.
CubeSat.Info
The CubeSat is a pico-satellite design from Bob Twiggs
of the Stanford's Space
Systems's Development Laboratory and developed in
collaboration with Cal Poly State University at San
Luis Obispo. The motivation is to develop a standard,
off-shelf satellite small satellite kit that can be
cheaply built, easily adapted for different missions,
and launched in clusters so that per satellite launch
cost will be low.
A Cubesat is about 10cm per side and weighs a kilogram.
Student groups should be able to build and launch a
cubesat for around $50k. Eventually, multiple cubesats
will work together in formation to provide the capabilities
of a single large satellite.
"...The main objective of this initiative is
to create a network of students, educational institutions
and organisations (on the Internet) to facilitate
the distributed design, construction and launch of
(micro)-satellites and potentially more complex projects
such as a moon-lander."
The long term program
goal is to build a lunar orbiter and then a lunar
lander with a rover.
Electra
- "a cubesat class spacecraft modified
to take advantage of a rocketpod form factor. RocketPod
is an externally mounted deployment device designed
to make use of vacant positions on many Expendable
Launch Vehicle (ELV) housings. Electra will contain
a spool of electrodynamic space tether which will
be connected to the second stage of the Delta II booster
of the launch vehicle. Dragging against the magnetic
field of the Earth, Electra and her tether will pull
the booster from orbit. Demonstrating at once the
feasability of the RocketPod concept and the ability
of a conductive tether to provide a simple but powerful
drag."
The SSEL projects were discussed in the following interview:
Project
Starshine
The Student Tracked Atmospheric Research Satellite is
a small, optically reflective spherical spacecraft.
It was assembled by the Naval Research Laboratory in
Washington, DC from eleven hundred sets of aluminum
mirror blanks machined by Utah technology students and
shipped in kits by project officials to schools around
the world (see list of participanting
schools) where students polished
the blanks.
The satellite (diameter of 48cm or 19in) will be very
bright and easily visible to the naked eye. The satellite
will be tracked by students who will record their observations
online. Gradually the satellites orbit will decay and
the rate of the decay will be proportional to how much
the upper atmosphere is heated by solar activity. Thus
monitoring of sunspots is part of the project activities.
StarShine will be deployment by NASA from a Hitchhiker
canister on the Space Shuttle Discovery into a highly
inclined low earth orbit on mission STS-96 in May of
1999.
Project
Starshine Telemetry - Starshine 3 also has an amateur
radio transmitter. This site will gather and disseminate
"Project Starshine telemetry data submitted by
students and hams around the world." For details
on communicating with Starshine 3, see communication
system specs.
FLASH
A student group at Brown university is developing the
FLASH
spacecraft with the goal of ramming it into the Moon.
The purpose of this is explained
as follows:
Meteoroids routinely hit the Moon’s surface. In December,
for example, one meteoroid hit the edge of Mare Imbrium
with the force of about 150 pounds of TNT, creating
a flash as bright as starlight. Meteoroids also pelt
Earth, but the debris burns up when entering the atmosphere
– a protective layer that the Moon lacks.
Right now, however, scientists can’t accurately calculate
the size of meteoroids that hit the Moon. By slamming
a spacecraft with a known size, weight and speed onto
an area with a predetermined mineral make-up, FLASH
would create baseline data that would allow scientists
to calibrate the size of meteoroids that create natural
lunar impacts.
LunarSat
This university student project has designed a
"100kg micro-satellite to be launched at the
beginning of the third Millennium to investigate the
Lunar South Pole's suitability for the first permanent
human outpost.
It will research the morphology and mineralogy of
the Moon's surface, determine the physical properties
of the Lunar exosphere and magnetosphere and, above
all, will look for sub-surface water deposits.
This European space project is primarily being designed,
built and operated by young spaceprofessionals and
students."
A primarily German university project. "LunarSat
mission is currently operated by a cluster of Universities
under the lead of the Astronautics Division of the Technical
University of Munich/Germany" with support from
ESA.
The project involves a number of educational outreach
projects such as a MoonCivilization online game
with the main aim of virtually colonization of the Moon
by "MoonTeams".
PongSat
This fun concept has been developed by the amateur rocketry
group JP Aerospace
and now has several hundred students involved.
Simple table tennis balls are split and
the students put some sort of experiment inside. It
is then sealed up for launch.
JP Aerospace took some pongsats up already
in a high
altitude balloon and expects eventually to launch
them with their Microsat
launchers to space.
The experiments range from the extremely
simple, like studying the effects of vacuum on a marshmallow,
to the quite sophisticated, like a cosmic ray counter.
CanSat
at AAS
Student participants in this annual contest will see
their soda-can sized payloads go to only a mile high
or so but they will learn many of the techniques and
technologies required for building and flying orbital
spacecraft.
Dobson
Space Telescope
Students in the Department of Astronautics at the
Technische Universität Berlin, Germany are developing
a clever compact telescope design for space. A prototype
of the will be tested in microgravity during a parabolic
flight.
Mars
Gravity Biosatellite - see Space
Science section
The satellite will spin to simulate the Mars gravity
for the 15 mice living onbard. It will provide data
on the "effects of partial gravity on mammalian physiology."
The EyasSAT ESS™ is a set of circuit boards
that plug together to form a complete satellite.
Each board or module functions as one of the
sub-systems. They stack by plugging them together
using connect-through headers. Add a case
with separation switch, solar panels, light
sensors, and a thermal control surface and
you have a complete satellite for the lab
environment.
"..operate a communications payload aboard
an Australian satellite in 2002, a key component
of the Store and Forward Mars Analogue Research
System (SAFMARS) project. SAFMARS will allow email
communication between isolated locations including
Mars Society Research Stations and the internet.
Mars Society members will be able to communicate
with remote field crews from the comfort of their
own home and the system will allow monitoring
and control of research assets anywhere in the
world, year-round..."
Kolibri-2000
The Kolibri was a small satellite developed in Russian
as a non-governmental, non-commercial project for
students. (It is a follow-on project to the Spoutnik
satellite mentioned below.)
The satellite was taken to the ISS in November 2001
on a Progress re-supply ship. It was released by
remote control from the station in late February
2002.
Russian and Australian students communicated with
the satellite over amateur satellite frequencies.
It carried several scientific sensors including
a magnetometer and charged particle detector whose
data the students monitored.
The spacecraft re-entered the atmosphere in April
of 2002.
