The Team:

In its infinite wisdom, NASA has decided to assign the team members pseudo-randomly. As this is a team project, the team members must work together. Part of this assignment is to let you experience a little of what it is like to work on a team that you do not necessarily have control over the membership of! (I have been on many of these.) It is usually best if individuals have assigned tasks, such as those listed below. In particular, your proposal should have a personnel allocation section where the duties are outlined. In addition to submission of a proposal (by email, to me), the team will be responsible for a one-page press release which will be posted here on the web, and a mission web-page if the group decides to do so for extra credit.

A list of required and suggested personnel tasks (those marked as required you must have a single team member assignent to, though one person can fill several roles):

• Overall Mission Principal Investigator - one required
• Individual Spacecraft Principal Investigators - two required
• Chief Astrogator and Liason to Mission Control - one or two required
• Press Liason Officer (eg. web-page development, press releases) - one or two required
• Head of Imaging Team
• Head of Atmospheric Analysis Team
• Head of Planetary Surface Exploration Team
• Head of Planetary Impact Probe Team
• Head of Orbiter Telemetry Team
• Head of Magnetospheric and Plasma Wave Team
• ... you should feel free to make up your own team leaders in conjunction with your management plan!

To help guide you as to what the members should do, I have added a list of questions that should be answered.

The Proposal:

You should include in your proposal:

• The name or acronym for the mission
• The team members and their areas of responsibility
• The primary target planet for the mission, and possible secondary target(s)
• Whether it will concentrate on the planet or satellites
• The planned course and closest approach to the target. Some correction on approach can be made if instructions are given (eg. "measure radius using angular size and distance, compute Roche limit 2.5 radii, and approach within 3 planetary radii").
• The scientific goals of the mission and its instruments, particularly in the context of big astronomical questions (such as life in the universe, the formation of solar systems, differences in planet composition, planetary atmospheres, etc.)
• Choose delivery platform: flyby or orbiter
• A list of instruments, the budget, and the weights of each
• Weight allowance is total of 100kg. Total masses of all components including platforms, probes, power supplies, etc.
• The maximum budget is now reduced to $75M. The grant administrators at NASA will return your proposal for revision if you exceed this! Total the costs for all components.
• Make sure you have enough power available to run the instruments. If limited power is available, state when you want it to turn on and off.
• Because of the distance to the system, and the long communication delays, the mission will have to operate in autonomous mode. State any particular instructions for contingencies or targets of opportunity above the normal operating instructions provided by the NASA Spacecraft Systems Operation Team to program into the on-board computer expert system.
• The total budget and weight. Make sure this is $75M, 100 kg or under.
• Management plan for how the team personnel will divide up the proposal, mission control, and data analysis (pretending for a moment that the mission will actually return data) tasks.

The mission propsal should be emailed to the Mission Coordinator as soon as possible!.

Common Errors and Problems:

• To deploy a micro-rover, you must land it on the planet using a soft lander.
• To use the soil analyzer/life detection experiments, you must use a lander or rover/lander. A hard impact probe or atmospheric probe are not sufficient.
• To use the atmosphere sensor/analyser, you must be able to get into the atmosphere with an atmospheric probe, hard impact probe, or soft lander.
• The orbiter is equipped with retro-rockets so it can be slowed into planetary orbit. No gravity assists are needed to slow it down.
• The flyby is ballistic except for small thrusters, so it needs gravity assist to re-direct its path into closed orbits. It is primarily designed for a fast flyby on a hyperbolic trajectory.
• Aerobraking and gravity-assist in this unexplored system are very risky. Use with caution! Missions can often be accomplished without this (use an orbiter instead of flyby, etc).
• It is a good idea to include at least a Low-Resolution Video Imager (LRVI) on an orbiter to allow visual selection of a landing site for a lander or probe! You can choose to deploy blind, but its probably be best to be careful.
• Choice of landing site can be crucial. A good (but short) set of instructions and options can make all the difference. The on-board AI may be able to calculate fast, but it can't think itself out of a paper bag on its own!
• No extra equipment is now need if you want to communicate with other missions to share intelligence, data, or telemetry. However, both mission proposals (and onboard programming) must state this fact so that common codes and formats can be agreed upon.

Hints:

It is best to pick an overall planetary and scientific target, like "see if there is life on Planet X" or "determine internal composition of Planet Y" or "image satellites of Z". Then make sure your mission does this. Then, see what else you can put on the mission that will be complementary. Let me know if you are having troubles with this. Your mission(s) should focus on one or several questions. Talk it over with your team members as well as other temas - try and design complementary and innovative missions! Try and think of missions that would show us something special. I don't want to see 20 versions of the same mission :-(

If you want a guide, look at the proposal for an example mission. Of course, don't just copy this one - I would not be happy about that!

I know you would like to make a mission that does "everything", but this system is set up so that you can only get a good shot at one primary target planet. With 20 separate proposals and 6 chosed missions, no one mission need do everything! Some redundancy is OK but try and do something different.

Keep an eye out for power requirements. Check to see what you expect the flux from the star to be at the various planets if you want to use solar panels, so you can decide how many to include. Panels and the nuclear generator produce power (in Watts), but batteries contain a fixed amount of energy (in KW hr) that can provide a given number of watts for some time ( 1 kW hr = 1000 W for 1 hr, or 1 W for 1000 hours, etc).

Be sure you include a computer for every 3 instruments! If some instruments need to remain running on the orbiter when the probe is dropped, make sure there are enought DPUs on both. If you want to have probes or landers, then put most of your instruments on them, instead of the orbiter if you can to save power and DPUs.

Think of simple instructions to give the on-board AI, like "look for large satellites, see if they have an atmosphere, if so, drop probe there; else, drop probe into main planet". Good instructions can make the difference between an OK mission and a great mission!

If you find the choices too complicated, keep it simple! There is no single "right" answer, this is exploration.

If you have ideas for other instruments, let me know. For example, you might want to have "float balloons" to allow an atmospheric probe float in thick atmosheres instead of just falling until its crushed. Or you could have "airbags" like Mars Pathfinder to allow a hard impact probe or atmospheric descent probe land on a low gravity planet or larger satellite (not too high a gravity so it doesnt just crash, but high enough gravity that it doesnt just bounce away!).

What Comes After:

After proposals are handed in, I will choose a suite of the best 5 missions to be "launched". Data will generated from these missions, and will be appear in the final exam and sample problem set.

I hope this proves useful and entertaining after all those boring computations we did. Try and remember what we did and why, and think of how to use them to find things out about other planetary systems.

Team Member Questions and Responsibilities:

Here is a list of the sorts of things you should be thinking about. I am not asking for complicated things like the actual orbits needed.

• Overall Mission Principal Investigator

  Nothing special here - the PI is in charge of checking over the whole proposal, making sure the budget and masses are correct, and that everything that was asked for is there!

• Individual Spacecraft Principal Investigators

  What tradeoffs were made in the choices of the instruments? Also, you are in charge of the individual spacecraft budgets and weight allowances. Remember, the $75M and 100kg are for EACH spacecraft individually!

• Chief Astrogator and Liason to Mission Control

  What is the circular orbital velocity of your target planet around EPS451 (this is the velocity your spacecraft will need to catch the planet)? If you have an orbiter, what is the orbital velocity around the planet you want (guess based on an assumed density to get mass of planet)? If you are planning a tour of planets, what sort of least-energy transfer orbit would be appropriate? What are the power requirements and thus will solar panels work?

• Press Liason Officer (eg. web-page development, press releases)

  What are the scientific goals of your mission (in terms the public would be able to understand)? How does the science relate to big questions such as life in the universe, how our solar system formed, etc? Are there technology spinoffs?

• Head of Imaging Team

  What is the resolution and field of view desired from the camera? What sort of things are you looking for?

• Head of Atmospheric Analysis Team

  What sort of atmosphere do you expect? What are you looking for? What will it mean if you find it?

• Head of Planetary Surface Exploration Team

  What sort of region do you want to land in? Why? Are there geographic constraints (ie. polar vs. equatorial)? How will the AI recognize it from orbit? If you have a rover, what will it do? What sort of things will it be programmed to watch for?

• Head of Planetary Impact Probe Team

  What is the target region? Why? How will the AI recognize it from orbit? What are you looking for?

• Head of Orbiter Telemetry Team

  What sort of orbit (equatiorial, stationary, polar) is desired and why? Are there power consumption and generation issues in this orbit (eg. will the Sun be eclipsed)? What sort of information will be sent to/from landers or probes? What sort of info will be processed onboard, and what will be sent directly to Earth?

• Head of Magnetospheric and Plasma Wave Team

  What are you looking for? Do you expect a big signal? Will the stellar wind be large or small where your probe is? Are you in a nasty radiation environment?

Mission Homepage ---

smyers@nrao.edu   Steven T. Myers