Mars Sunphotometer Group

Industry Advisor: Dr. Strawa

Advisor: Dr. Papadopoulos

Student Team Lead: Matthew Velante

Agenda

• Current Objectives• Timeline• Technical Reports• Website• Future Objectives• Team Members• Team Structure• Discussion

Current Objectives

• Fast work pace.

• Completion of technical research within one week. Items required:– Equations– Formulae– Physics

TimelineOctober November December January February March April May June July

ResearchWavelength

Eric, ShabanaOptics

Winston Cone ,Ray TracingChristian, Justin

Spectra DispersionScattering Device

Matt, ChrisSystem Sizing

CCDDan, Bao

Advanced ConceptsMatt

Platform ApplicationsMatt, Bao

Sensor DesignOptics - Christian, Justin

TypeSizingWeight

Scattering Device - Dan, BaoTypeSizingWeight

CCD - Dan, BaoTypeSizingWeight

IntegrationSystem Bus

StructurePowerThermal

PayloadOpticsScattering DeviceCCD

System EngineeringLead - MattAssistants - Eric, Justin

PDRCDRFDRWeekly Student Reports3rd Interplanetary Probe Workshop

Report WritingPresentation in Greece

Tasks

Technical Reports

• Wavelength

• Winston Cone/Ray Tracing

• Dispersion Technique

• CCD

Wavelength:

Objectives:• Determine which chemicals sunphotometer

should recognize• Research spectra of chemicals of interest• Investigate necessary abilities of CCD array• Investigate alternative designs of

sunphotometer

Important Elements of the Martian Atmosphere

Atmospheric composition (by volume): Major : Carbon Dioxide (CO2) - 95.32% ; Nitrogen (N2) - 2.7%

Argon (Ar) - 1.6%; Oxygen (O2) - 0.13%; Carbon Monoxide (CO) - 0.08%

Minor (ppm): Water (H2O) - 210; Nitrogen Oxide (NO) - 100; Neon (Ne) - 2.5; Hydrogen-Deuterium-Oxygen (HDO) - 0.85; Krypton (Kr) - 0.3; Xenon (Xe) - 0.08

Past Experimentation• Whiting-

Determination of Mars Atmospheric Composition

“The Right Tool for the Job”

• Expected spectra and conditions on mars will determine the necessary attributes of a CCD array for the sunphotometer

• The array must meet conditions for: pixel size light sensitivity operating conditions physical size and accuracy

• Array should be lightweight, durable, and draw as little power as possible

Other Design Possibilities

• Another possibility for a hemispherical viewing devise might be a reflecting cone.

Winston Cone Design

Source:http//scienceworld.wolfram.com/physics/WinstonCone.html

Initial Parameters

• Entrance Aperture of 2.00 mm

• Ray angle range from zenith 18-89 degrees

Winston Cone Equations

=

Winston Cone Equation in (r , z) coordinates:

Inverting the Equation:

Dimension equation:

=

Dimensions

• Entrance Aperture radius: 1.00 mm

• Exit Aperture radius: 3.236 mm

• Cone Height: 13.037 mm

• Focal Length: 1.309 mm

Note: All dimensions are based on 2.00 mm aperture size and 18 degrees off the zenith inclination.

Concerns

• Size of Cone

• Manufacturing

• Interface (CCD)

Dispersion Technique

• Matt and Chris C. have just been assigned to this task.

CCD• 2-D array is chosen as the incident light

moves across the sky, the dispersed spectrum moves across the array area.

• Using the determined wavelength spectra, the CCD material will be determined.

CCD

• Important Detector Parameters

CCD

• Equations:

WA

PeaksitivityRadiantSen

HZ

AntNoiseCurre

NEP@

Website

• Current Website: http://groups.yahoo.com/group/MARS-SunPhotometer-Team/

• Future Website:• http://www.engr.sjsu.edu/cest-e/

Mars_Sunphotometer

Future Objectives

• Submit proposal for NASA Ames DDF.

• Minimum of two publications to be produced (for AIAA, JANNAF, …)

Team StructureTeam Leader Advisors/Mentors

Tasks

IntegrationResearch

Team Members

Design

Team Members

• Dr. Strawa – Industry Mentor/Advisor

• Dr. Papadopoulos - Mentor/Advisor

• Matt – Student Team Leader

• Student Team Members: Eric, Justin, Dan, Bao, Christian, Shabana, Chris C., Mike

Discussion

• Status: NASA Ames Director’s Discretionary Fund?