Proposal
Mercury Lander Mission
Spring 2012
Science Question: What would be the velocity and distance covered by a solar sail deployed
from the orbit of Mercury and powered by the light of the sun?
The purpose of a solar sail is to obtain and manipulate light from the sun to travel through
space without the consumption of fuel. Solar Sails have been around for many years and have
been successful in space travel. The Nanosail D2 is a great example of successful space travel. It
was launched successfully from the Minotaur IV spacecraft in Earth’s orbit on November 19,
2010. It was deployed from the Minotaur IV spacecraft on January 19, 2011. The sail was
constructed at the Marshall Space Flight Center. The purpose of the Nanosail mission was to
demonstrate and test the deorbiting capabilities of a large low mass high surface area sail. The
sail orbited around Earth for 240 days performing well, but burnt up in the atmosphere on an
attempt to re-enter Earth. The Solar Sailors will undertake a journey to Mercury aboard The
University of Alabama Huntsville’s Quicksilver spacecraft. The journey to Mercury will take an
estimated five years, and just before arrival to the planet, the Solar Sailor’s solar sail will deploy.
Onboard instrumentation will then determine velocity and sail position.
Engineering Requirements
Table 1. Science Traceability Matrix
Science Objective
Measurement
Instrument
Objective
Selected
Measure Velocity of
the solar sail
Locate position of the
Solar Sail
Velocity data
3 axis accelerometer
3 axis location data
3 axis accelerometer
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Proposal
Mercury Lander Mission
Spring 2012
Instrument
Table 2. Instrument Required Resources
Mass (kg)
Power (W)
Volume (cm3)
3 axis accelerometer
Analog Devices
AXDL346
Microcontroller
TI 430CCRF
Solar Cell
.002
(2.75V)(145µA)
.004
.05
(3.5V)(5mA)
.017
Battery (lithium)
TADIRAN TLH-5935
.021
Provides .18 W
(3.6V)(50 mA)
.3 x .3 x x.095
.009
Data Rate (bps)
2400
Solar Sail Concept of Operations
The Solar Sailor’s solar sail will be aboard the Quick Silver spacecraft. Before the Quick
Silver enters Mercury’s gravitational pull, the solar sail will be propelled a safe distance from the
Quick Silver lander and Mercury. The sail will be deployed quickly. This is to ensure that no
tangles occur in the sail. The sail will be constructed of CP-1. CP-1 is an ultra thin and highly
reflective material. CP-1 is in a family of polymers that are called polyamides and has been used
in space applications for many years. This material will be responsible for reflecting light
particles off its surface. The light particles from the sun will be traveling at the speed of light,
which is 299,792,458 m/s. Once these particles hit the sail, the sail will be able to travel vast
distances with no fuel consumption.
Design Alternatives
The Solar Sailors initially came up with three different types of Solar Sails. These sails
varied in sizes and shapes. Each one of them also had a different method of deployment. As each
idea was reviewed in terms of mission requirements, efficient deployment, and durability, a final
design was chosen.
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Proposal
Mercury Lander Mission
Spring 2012
Alternative Designs
Spherical sail
Umbrella-like deployment
Final Design
As a group, the Solar Sailors decided on a design for our solar sail, HSEP.
HSEP stands for Helical Space Exploration Platform. The shafts will be made from carbon
fiber. The 100 square foot sail will be made of CP-1 material. The sail and instruments will
be housed in a 4” x 5.5 in” cylinder also made from carbon fiber. The shafts will unwind like
tape measures. The tips of the sail will be connected to the ends of each shaft.
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Proposal
Mercury Lander Mission
Spring 2012
HSEP Dimensions
Deployed
•
10 ft
10 ft
5 ft
4 in
Packaged
5.5 in
HSEP Shafts
Shafts
1.5in X .02 in
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Proposal
Mercury Lander Mission
Spring 2012
Deployed Sail
Component
Table 3. Mass and Power Budget of HSEP
Number
Mass
Power (W)
Total
(kg)
Mass
(kg)
3-axis Accelerometer
1
.002
(2.75)(145ua)
.004
Microcontroller
TI 430CCRF
Solar cell
Battery
TADIRAN
TLH 5935
1
.05
1
1
.021
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Total
Power
(W)
.002
.004
(3.5V)(5mA)
.017
.05
.017
Provides .18
W
.021
+.18