Did you know there are toaster-sized spacecraft
orbiting around the Earth?
Today we're looking at the world of CubeSat:
Space science on a budget!
What's a CubeSat?
So, you can't afford millions of dollars to
launch a satellite, but still want to carry
out scientific investigations in or about
the rigors of space?
Have we got a satellite for you!
This satellite has a volume of a little more
than five Rubik's Cubes.
That may not seem like a lot at first glance,
but with miniaturization technology on your
side you can fit a lot inside a cube measuring
10 x 10 x 11.4 cm on each side.
The extra length is to hold required technology,
so that leaves exactly one liter of useable
space for the project itself.
Origins
The CubeSat project was born in 1999 at California
Polytechnic State University and Stanford
University as a platform for students to learn
about developing, building, launching, and
performing an actual space mission.
The first mission was launched four years
later in 2003, and well over 1,200 CubeSats
have followed since.
So far, only ~80 have been lost in launch
failures and fifty countries have participated
in the project.
This had advanced research and saved governments
millions or billions…
Size Matters
Just look at all the technology packed into
your average cell phone.
There are usually five radios with four two-way
transmitters and a GPS receiver.
They have position, acceleration, movement,
light, temperature, pressure, sound, speed,
and rotation sensors, among others.
They are sturdy solid state devices, rugged
enough to tolerate a space launch.
Some have already been employed in this fashion.
Without a screen they can run for days on
a single charge, but a couple of solar cells
generate enough power to keep it running constantly.
They can record data, take pictures, create
videos, and make a good base for designing
a CubeSat.
There is more advanced tech in a cellphone
than the Apollo astronauts had to get them
to the Moon and back!
Realistically, of course, the success of the
program has led universities, institutions,
and governments to develop purpose-built tech
that consumes even less energy and space,
and eschews superfluous extras to save weight.
This provides a test bed to create flight-proven
hardware at minimal cost before an organization
or government builds an actual satellite for
launch.
A single satellite could be very useful for
one specific experiment that students might
like to conduct (what do spiders build for
webs in space?), or for continual observation
(why is the Sahara getting greener?).
It could be used as a testbed for a mercury
vapor powered ion engine, or any sort of one-off
technology testing.
Constellations of satellites can also be very
useful.
They can share data and expand their reach
and capabilities when working together.
For example, even though his project is not
a part of CubeSat, Elon Musk wants Internet
access for everyone, from anywhere on Earth,
and he wants to do that with a constellation
of satellites in low orbits.
Live & Learn
Musk's venture has turned out to be a bit
of a learning experience for all concerned.
For example, his people didn't consider that
they ought to make the satellites black, or
at least not shiny and reflective.
The first ones have been photobombing quite
a few astronomical images, much to the annoyance
of astronomers.
Of course, that is exactly what these CubeSat
missions are for…to teach the rest of us
how to avoid future mistakes!
How Many Can We Launch?
A standard launcher rack, called a P-POD for
Poly-Pico-satellite Orbital Deployer, is rectangular
box that can hold up to 3 Cubestat units.
This can be added to any rocket that has extra
capacity, or delivered to the International
Space Station (ISS) and launched from the
Japanese module's airlock.
These devices are spring launched, without
rocket motors, so there is no chemical residue,
escaping gases, or anything that would interfere
with the ISS operations.
Other Sizes
Of course, whenever you're told there is one
size available, people demand variety.
Consequently there have been a number of variations
developed.
The sizes are measured in Units, with the
10 x 10 x 11.4 cm forming the 1U CubeSat.
Now they are available in 0.5U, 1U, 1.5U,
2U, or 3U from the standard launcher.
Still unsatisfied, more sizes have been developed.
Because a 3U unit only needs one spring deployer,
this provides a bit of extra tubular space
on one end.
This is usually used for a propulsion system
or antenna array.
CubeSats are proving so useful that they are
being used for more than technology validation
or academic work.
Now they are being re-sized to suit much larger
scientific goals and even national defense
projects.
Fast, Cheap, Temporary
These satellites use off-the-shelf technology.
This is Plug-n-Play science and that makes
them very inexpensive.
Better yet, when people are worried about
adding more debris to our already crowded
orbits, we can reassure them because these
units are launched low enough that they inevitable
succumb to atmospheric friction and fall out
of orbit to burn up in the atmosphere upon
re-entry.
That's not to say these are one-day missions…no,
no, no!
These are designed to operate for between
3 and 12 months, depending on need.
You can collect a lot of data in a year if
you need it that long.
What Have We Done So Far?
MarCO
While the list is long in the near-Earth vicinity,
by far the most interesting was the pair of
CubeSats named EVE and WALL-E (after the animated
stars of a PIXAR film).
Their mission was dubbed MarCO, for Mars Cube
One, that left orbit along with the INSIGHT
mission to Mars.
Their purpose was to perform real-time reporting
of the INSIGHT lander as it made its way to
the Martian surface.
WALL-E also provided imaging and relayed INSIGHT's
images from the landing site.
EVE conducted some radio-related science,
too.
They achieved their goal admirably, and confirmed
the ability of CubeSats to operate beyond
Earth's orbit.
The radiation environment above LEO (Low Earth
Orbit) is harsh and equipment needs to be
radiation hardened to survive.
Ordinary gear can manage for a reasonable
time in LEO, so that keeps costs down for
early participants.
They stopped chattering to us about 33 and
39 days after they completed their missions.
Total time ~8 months.
Result: great success.
Asteria
ASTERIA was the first Jet Propulsion Laboratory
CubeSat to work in space.
It was a 6U model designed to prove pointing
capability for stellar photometry and precise
temperature regulation/thermal stability of
the CMOS imaging device (like the camera found
in some cellphones).
It succeeded amazingly well in both of these
areas.
CubeRRT
Microwave pollution of the radio spectrum
won't decrease anytime soon.
This mission was designed to mitigate the
effects of manmade interference in the microwave
spectrum.
The RFI is compromising the ability to retrieve
geophysical information from satellites.
Hopefully the data obtained will improve the
ability to mitigate data corruption for soil-moisture,
wind-direction & speed, salinity of the sea-surface,
precipitation, and atmospheric water vapor
content.
GRIFEX
GRIFEX was a successful 2015 3U technology
validation mission of a sophisticated pollution
tracker that utilized high-throughput data
handling to increase the speed of reporting
for highly volatile conditions where pollution
is moving rapidly.
M-Cubed/COVE
The 2011 Michigan Multipurpose Minisatellite
(M-Cubed) carried the 1U COVE (CubeSat Onboard-processing
Validation Experiment).
Unfortunately it became magnetically attached
to another CubeSat during deployment.
The satellite could not be controlled in any
way rendering it useless.
This necessitated a second launch of the MMM/COVE-2,
in 2013, whose mission remained the same:
take mid-resolution images of Earth, while
engaged with COVE.
COVE's purpose was to use the photographic
information as fodder for its new processing
algorithm to reduce the data rate by two orders
of magnitude, deliver the same data, and all
without losing any useful science information
in the process.
This entailed using a Field Programmable Gate
Array (FPGA), which is essentially a powerful
parallel processer that is more capable than
the traditional variety.
It can be reprogrammed after manufacture to
accommodate new functionality.
The one they chose was the radiation-hardened-by-design
Virtex5-QV FPGA by Xilinx.
What is planned?
Lunar Flashlight
Ready to launch in late 2020, Lunar Flashlight's
mission is to map the South Pole of the Moon
using lasers to identify water ice deposits.
This 6U CubeSat will use some of the same
components as the MarCO mission mentioned
earlier.
Not incidentally, it will be the first CubeSat
to reach the Moon.
NASA needs to expand the body of knowledge
that tells where water could be located on
the Moon in useful quantities.
CAPSTONE
This mission will check out Lunar Orbits for
viability as well as new techniques for maintaining
those orbits.
Its full name is Cislunar Autonomous Positioning
System Technology Operations and Navigation
Experiment which boils down to making sure
it is safe for a Moon-orbiting outpost.
CPOD
This is an experiment to demonstrate two CubeSats
working in close proximity and successfully
docking between the two.
It's a testbed for many miniaturized technologies
that we will need in the near future.
PTD
The Pathfinder Technology Demonstrator will
showcase many new technologies.
For example, laser communication with the
ground will significantly increase data throughput.
It also looks to investigate new technologies
to stabilize the spacecraft, and to maneuver
it including leaving orbit and head into deep
space.
The Takeaway
The CubeSat platform can only make life better
for small technology companies looking for
an easy way to access the space development
market.
The fact that it is evoked the interest of
industry and government makes it clear that
this is not some fleeting interest that stunned
and finished one day.
This is how we're going to get to the future—not
by leaping into the air like Superman—but
by ascending a long stair case, step-by-step…
If you could launch a satellite in space,
what would you have it do?
Let us know in the comments below and then
check out this next video that you might find
interesting!
