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Peddawandla | 1
Voyager 1 and how to send your smartphone on an interstellar adventure
Thirty-seven years ago NASA’s Voyager-1 spacecraft was launched into space powered
by technology far less advanced than that built into the average modern smartphone. The
smartphone can process and complete significantly more tasks than Voyager-1 – billions
of miles away from Earth – can. Could this mean that, with a few modifications, a
commonplace device such as a mobile phone could perform just as well in interstellar
space as Voyager has? If not, what features of the Voyager spacecraft set it apart and if
yes, what could this potentially mean for the future of space travel?
Author Ruthvik Peddawandla
About the Author Ruthvik is a Junior majoring in Electrical Engineering. When he’s
not pondering the many mysteries of life and the Universe, he may
be found in various spots around campus, desperately struggling to
make sense of his Engineering textbooks.
Prepared on 02/24/2014
Prepared for Prof. Marc Aubertin – Writing 340
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Introduction: The Importance of Space Exploration
The year 1969 is immensely significant to the human race for two reasons. The
first is that it brought with it the release of the Beatles’ revolutionary anthem, Yellow
Submarine. The second, and perhaps slightly more noteworthy reason is that it was the
year man succeeded in breaking his corporeal boundaries by expanding his nomadic
tendencies into the stars. On July 20th 1969, Neil Armstrong and Buzz Aldrin became the
first human beings to land on a surface that was not the Earths; thus contributing greatly
to our relentless pursuit of trying to understand our celestial neighborhood and
significance in the Universe.
The importance of our ventures into the cosmic unknown was recognized even
then – five decades ago. It is crucial to acknowledge the mortality of our dear own Planet
and that it when its resources are depleted and it grows incapable of supporting the
exponentially growing populace, we will need to sail into the daunting Universe and set
up home wherever we safely can. In the words of inspirational astronomer and science
writer Carl Sagan, “The Cosmos extends, for all practical purposes, forever. After a brief
sedentary hiatus, we are resuming our ancient nomadic way of life”1.
Today, in 2014, space exploration is as relevant to our advancement as a species
as ever. Unfortunately, it’s been forty-two long years since any man last set foot on even
the Moon. However, this is not for a lack of the ready availability of the necessary
technology – over half of American adults hold, in their pockets, a smartphone with
1 C. Sagan, (1994) Pale Blue Dot: A Vision of the Human Future in Space, pp. 334. [Online]. Reprint Edition, September 8th 1997. Available: http://goo.gl/Z2f94y
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processing and memory capabilities thousands of times more powerful and smaller than
the computer that guided Apollo 11 to the moon2,3. Every instruction carried out by the
Apollo Guidance Computer aboard Apollo 11 can potentially be executed by the average
modern smartphone in a fraction of the time. Could this possibly, somehow mean the
dawn of a new, personalized, mainstream age of space exploration then? Could we
potentially be able to modify our smartphones to take on the harsh unknown of Space?
To answer this question we could compare a modern smartphone to an unmanned
spacecraft, sailing at the edge of the Solar System, also equipped with computers
significtunesantly less advanced than the ones we use to run Temple Run – Voyager 1.
Other than the obvious fuel and propulsion machinery, what really allows
Voyager 1 to function so far away from home and how, if at all, can this implemented
into a modern mobile communications device?
2 PewResearch Internet Project. “Mobile Technology Fact Sheet”. Internet: http://www.pewinternet.org/fact-‐sheets/mobile-‐technology-‐fact-‐sheet/, Jan 2014. [Feb 23rd 2014] 3 John Pavlus. “3 Design Strategies that let Voyager 1 Survive Interstellar Space.” Internet: http://www.fastcodesign.com/3017866/3-‐design-‐strategies-‐that-‐let-‐voyager-‐1-‐survive-‐interstellar-‐space, Sept. 23rd 2013. [Feb 23rd 2014]
The Apollo Guidance Computer -‐ Surface Area: 1952 cm2. Weight: 70 lbs.
Apple A7 Processor Chip – Surface Area: 102 mm2. Weight: Negligible.
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The Space Faring Smartphone Rocket
Before delving into that question though, it may be necessary to answer another,
rather disconcerting question that some of you may have developed over the course of
this article – why, at all, is there a need to compare a smartphone to advanced spacefaring
technology? The answer lies in the indirect potential applications of the occurrence of
such a phenomenon.
If modern technology has progressed so rapidly that the power to send a machine
into space is within reach of the common man, a whole new era of space exploration may
be just around the corner – and open source age of space exploration technologies. The
introduction of new, innovative methodologies and discoveries of all things
extraterrestrial may become regular occurrences. We will make leaps and bounds in the
understanding of our cosmic neighborhood and more importantly, in the search of finding
a new home for when humans become too
great of a burden for the Earth to bear.
Voyager 1
Nineteen billion kilometers from the
Sun, a little piece of Earth floats boldly and
quietly into the realm of interstellar Space4.
Voyager 1 and 2 were launched in 1977 as part
of NASA’s Voyager program to study the
4 NASA & Jet Propulsion Laboratory. “Where are the Voyagers”. Internet: http://voyager.jpl.nasa.gov/where/ [Feb 23rd 2014].
Pictured: Earth.
Taken from a record 6 billion kilometers away by Voyager 1 in 1990
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planetary systems of the distant gas giants, Jupiter and Saturn. Voyager 1 currently lies
approximately four billion kilometers ahead of Voyager 2 and is responsible for
transmitting some of the most humbling knowledge back to scientists on our home planet.
The total cost of the Voyager program has been approximated at nearly $900
million5. This alone may thwart us from even considering the possibility of sending a
sub-$1,000 smartphone into the harsh conditions of outer Space. However, this figure
takes into account the various instruments, ground control software upgrades and
research spending that we may deem superfluous to our simple goal of sending a
smartphone into the Universe. A smartphone may not be able to perform all the tasks
Voyager can but if only the components of the spacecraft absolutely fundamental to it’s
functioning were considered, perhaps the similarities between the two won’t be so
difficult to find. Of these fundamental components, few are more crucial to both
spacecraft and smartphone than the processor and memory units.
The Processor and Memory Unit
The Central Processing Unit (a.k.a. CPU, Processor) is the part of a computer
system responsible for handling and executing various instructions. The processor is
more or less has complete control over a computer system. The instructions that the
processor executes are fetched from a computers memory where data is either stored
temporarily or permanently. The size of a computers memory is a determinant of the
systems ability to perform complex multi level functions and its rate of reading and
consequently, executing instructions. All three computers aboard Voyager 1 each have
5 NASA & Jet Propulsion Laboratory. “ Fact Sheet. Internet: http://voyager.jpl.nasa.gov/news/factsheet.html [Feb 23rd 2014]
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access to around 68 kilobytes of memory6. In comparison, an iPhone 5S comes equipped
with a 1-gigabyte memory7. In other words, a typical iPhone has an incredible fifteen
thousand times more memory than the computers that control Voyager do.
The average modern smartphone processor is also significantly improved from the
integrated circuits serving the same purpose aboard Voyager, which in the words of the
NASA voyager team is “no real processor in the modern sense”8. Each computer on the
Voyager can process 8,000 instructions per second, a tiny fraction of the staggering 14
billion a second that the modern smartphone can9.
The computer systems aboard Voyager were programmed to translate and execute
instructions in technical language that is long outdated and thus inferior, efficiency-wise,
to the high-level languages smartphone processors operate with10. It’s safe to say then,
that a modern smartphone should be able to carry out all the necessary procedures to keep
all instruments and components functioning all that way from home with ease. Would it,
however be able to do so for 37 years – as Voyager has?
Battery Systems
6 John Pavlus. “3 Design Strategies that let Voyager 1 Survive Interstellar Space.” Internet: http://www.fastcodesign.com/3017866/3-‐design-‐strategies-‐that-‐let-‐voyager-‐1-‐survive-‐interstellar-‐space, Sept. 23rd 2013. [Feb 23rd 2014] 7 GSMArena. “Apple iPhone 5 Technical Specs”. Internet: http://www.gsmarena.com/apple_iphone_5-‐4910.php. [Feb 23rd 2014] 8 R. Pastore. “NASA Scientists Answer your Burning Questions About Voyager 1”. Internet: http://www.popsci.com/science/article/2013-‐09/nasa-‐scientists-‐answer-‐your-‐burning-‐questions-‐about-‐voyager-‐1, September 9th 2013. [Feb 23rd 2013] 9 C. Dewey. (Sept. 2013) “Voyager 1 just left the solar system using less computing power than your iPhone”. The Washington Post. [Online] Available: http://www.washingtonpost.com/blogs/the-‐switch/wp/2013/09/12/voyager-‐1-‐just-‐left-‐the-‐solar-‐system-‐using-‐less-‐computing-‐power-‐than-‐your-‐iphone/# [Feb 23rd 2013] 10 A. Mann. “Interstellar 8-‐track: How Voyager’s Vintage Tech Keeps Running”. Internet: http://www.wired.com/wiredscience/2013/09/vintage-‐voyager-‐probes/, Sept. 25th 2013 [Feb 23rd 2014]
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Voyager took three thermoelectric generators with it on its great cosmic
adventure. The generators are powered by a radioactive isotope - Plutonium-238, that has
a half-life of approximately 88 years (i.e. the isotope will decay to half its initial mass in
88 years). 37 years into the journey, the generators are consistently outputting a total of
350 Watts of energy – 120 Watts less than they started out with - and this number is
continuously falling by 4 Watts every year11. The fact that an advanced spacecraft can
run on a 470 Watt generator is exceptionally impressive considering that the average
refrigerator requires a 600 Watt supply to run12. The generators will continue to power
the many systems aboard the spacecraft for as long as they can and as the power output
decreases NASA will continue to disable the components it deems redundant.
On the other hand, at full charge, the typical standby battery life of a smartphone
is around 200 hours. The capacity of said battery is just under 5.5 Watt-hours. Having to
power the various systems that need to be fitted for deep space exploration would drain
the battery of all its charge within the first 15 minutes of the launch. To power even the
most basic of Voyager’s equipment, the smartphone would, without a doubt, need to be
powered by an external power source. However, a lot of Voyager’s most ‘basic’
equipment is heavily outdated (although complete care was taken to maximize the power
efficiency of the components back then) and modern versions of components such as the
processor would consume a lot less power.
Regardless, the smartphone would be unable to keep even modern hardware alive
for the 60 years Voyager is predicted to.
11 M. Thompson. “Voyager – journey from interplanetary to interstellar space”. Internet: http://www.sen.com/feature/voyager-‐mission-‐overview.html, Jan. 25th 2012. [Feb 23rd 2014] 12 DonRowe.com “How Many Watts Do You Need”. Available: http://www.donrowe.com/usage-‐chart-‐a/259.htm
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Communication Devices
The Plutonium-238 isotope that powers the generators are capable of keeping
Voyagers communications systems functioning for perhaps 22 more years13. After which
it will drift into the vast emptiness
of the Universe, forever lost to us.
As a follow up to that depressing
fact, here’s an interesting one:
Voyager’s communication signals
are sent back using a 23-watt
transmitter, which is only about 8
times stronger than that of the
average cell phone14. By the time
the signals make the 19 billion
kilometer journey from the edge of the solar system to Earth, the strength of the signals is
reduced so much (to 0.1 billion-billionth of a watt) that “NASA needs to use its largest
antenna, a 70-meter dish… just to hear Voyager”15.
13 A. Mann. “Interstellar 8-‐track: How Voyager’s Vintage Tech Keeps Running”. Internet: http://www.wired.com/wiredscience/2013/09/vintage-‐voyager-‐probes/, Sept. 25th 2013 [Feb 23rd 2014] 14 B. Chappell. (Dec. 2011) “Voyager Probes Aim for Interstellar Space, Four Decades of Travel”. NPR. [Online] Available: http://www.npr.org/blogs/alltechconsidered/2011/12/14/143710692/voyager-‐probes-‐aim-‐for-‐interstellar-‐space-‐four-‐decades-‐of-‐travel [Feb 23rd 2013] 15 A. Mann. “Interstellar 8-‐track: How Voyager’s Vintage Tech Keeps Running”. Internet: http://www.wired.com/wiredscience/2013/09/vintage-‐voyager-‐probes/, Sept. 25th 2013 [Feb 23rd 2014]
Pictured: Voyager 1's design and its gigantic antennae
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The range of a smartphone transmitter needs only to be enough to communicate
with a satellite in low, medium or high Earth orbit – at the very most 40,000 kilometers
above ground. Having to power a more powerful transmitter would be beyond the
smartphone battery’s default capability and would depend on the external power source,
if any.
Hardware Toughening
Space is a cold, harsh place. At any given moment, Voyager is exposed to high
levels of harmful radiation, extreme temperatures, magnetic/gravitational fields and
haphazardly flying space debris that could potentially de-calibrate, damage or absolutely
destroy vital components. To prevent any possible tragedies, Voyager 1 was built to be
one of the sturdiest machines ever made. For example, its electronic devices were
exposed to a process called radiation strengthening to make them resistant to possible
damage from intense Space radiation. The spacecraft was designed to withstand typical
background interplanetary temperatures that range from thousands of degrees Celsius to
minus 455 degrees Fahrenheit16. To put that in perspective, the lowest temperature ever
recorded on Earth was minus 135.6 degrees Fahrenheit17.
A modern smartphones recommended storage temperature is approximately
between zero and 100 degrees Fahrenheit. Beyond that range of temperatures, its
functioning may be seriously impaired. To withstand the temperatures Voyager faces on
a regular basis, the smartphone would have to be either made out of or encapsulated in
16 F. Cain. “How Cold is Space?” Internet: http://www.universetoday.com/77070/how-‐cold-‐is-‐space/, Jul. 2nd 2013. [Feb 23rd 2014] 17 NASA. “The Coldest Place in the World”. (Dec. 2013) Available: http://science.nasa.gov/science-‐news/science-‐at-‐nasa/2013/09dec_coldspot/ [Feb 23rd 2014]
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hardened metal alloys that may disrupt its telecommunication devices. This would require
the smartphone to be fitted with external antennae and a satellite receiver to add to the
growing list of add-on’s it would need to perform like Voyager.
Conclusion
Technology has come a long way since the days of Apollo 11 and the Voyager
spacecraft. Smartphones today are undoubtedly remarkable pieces of innovation that are
exponentially improving. The functions a modern smartphones processor can carry out in
comparison to the systems aboard Voyager-1 are, to say the least, incredible. However,
Voyager-1 is made of 65,000 individual parts and possibly the least remarkable of the lot
is its processor18.
Eleven thousand work years went into designing the perfect spacecraft (at the
time) and mission as part of the Voyager program. To point out just how much detail was
considered by the scientists of the program, here’s a little bit of information: 10,000
different trajectories were considered before launching Voyager-1 at the perfect date to
ensure it took advantage of a special gravitational field phenomenon (courtesy of Jupiter)
that occurs once every 175 years to assist it in its journey into the far reaches of the Solar
System19. No smartphone has ever been designed with that much care.
The hardware and software aboard the spacecraft, though vital and considerably
effective, are not what has made Voyager-1 the unanticipated success it is. The sheer
18 NASA & Jet Propulsion Laboratory. “Fact Sheet.” Available: http://voyager.jpl.nasa.gov/news/factsheet.html [Feb 23rd 2014] 19 NASA & Jet Propulsion Laboratory. “Planetary Voyage”. Available: http://voyager.jpl.nasa.gov/science/planetary.html [Feb 23rd 2014]
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amount of planning dedicated to designing the most efficient mission that was possible
within the Voyager team’s means mustn’t be underestimated.
It would be only fair to conclude by attempting to answer the primary question
asked in this article: can you send your smartphone to space with certain modifications?
Probably. Is it in the power of a single average smartphone user to do so? Certainly not.
Space exploration is a topic that both intrigues and concerns us all on a personal level,
but it will probably be years before the technology to carry out interstellar voyages moves
into the mainstream.