Can you trust what the spacecraft tells you?
A spacecraft cannot see itself. Everything it reports comes from instruments, and instruments are never perfect. Your team will fly the same manoeuvre twice, changing nothing except the quality of the instruments, and find out what that does to what the spacecraft knows about itself.
If the instruments get worse, does the spacecraft get worse - or does it just stop knowing where it is?
Learning outcomes · Grades 9–10
What you should be able to do, and the evidence that shows it.
- 01By the end of this mission, the learner will be able to quantify the gap between the truth error and the estimate error for each set of instruments, and demonstrate this by reporting both gaps with units.
- 02By the end of this mission, the learner will be able to model why the worst estimate error is far larger than the average, and demonstrate this by relating the peak to the frames flagged as poor quality.
- 03By the end of this mission, the learner will be able to test whether the estimate would meet a stated pointing-knowledge requirement, and demonstrate this by comparing both estimate errors against that requirement.
Before we start
A quick check of what you already know. There is no score.
The idea behind the mission
Two runs, one difference: the quality of the instruments. The manoeuvre and the controls are identical, so anything that changes came from the instruments.
Being somewhere and knowing where you are
These are two different things. A spacecraft can be pointing exactly where it should while its instruments insist it is somewhere else. Engineers keep the two apart on purpose: what is true, what was measured, and what the onboard software concluded.
Predict before you run
Before you run anything: if we fit worse instruments, will the spacecraft end up further from its target? Say what you expect and why.
With worse instruments, will the spacecraft end up further from its target? Say what you expect and why.
At least 20 characters — say what you expect and why.
Configure the mission
These are the two set-ups you will compare. They are fixed on purpose: if only one thing differs between your runs, anything that changes was caused by it.
Baseline case
Perfect instruments
Candidate case
Realistic instruments
- Write your prediction first.
- Change nothing except the instruments, so anything that moves was caused by them.
- The readings are simulated. No instrument on a real spacecraft was measured here.
Units stay attached to every result: angles in degrees (°), time in seconds (s), power in watts (W), energy in watt-hours (Wh), battery state in percent (%), and elevation in degrees (°) where available.
Run the Digital Twin
Fly it with perfect instruments first, then with realistic ones. Nothing else changes.
Baseline
Perfect instruments
Candidate
Realistic instruments
Run the baseline first so you have something to compare against.
Read the evidence
Look at the two lines. One is where the spacecraft really was. The other is how wrong its own estimate was. Compare them across both runs.
Run the Twin to produce evidence.
Make the engineering decision
Which set of instruments would you fit, and which number in your evidence supports that?
Which set of instruments do you recommend, and what evidence supports it?
What this does not prove
What this mission shows
- My prediction
- The truth-against-estimate comparison for both sets of instruments
- Where each number came from
- One thing this model does not cover
What it does not establish
- The instrument readings are simulated by a teaching model. No real sensor was measured.
- The onboard estimator here is a teaching estimator, not a flight-certified one.
- This lesson does not show how any particular real instrument would perform.
Name one thing this model does not tell you about real instruments.
Show what you understood
Formative feedback for you and your teacher. There is no official grade.
With the poorer instruments, where did the spacecraft actually end up?
Which number tells you how wrong the spacecraft was about itself?
Which set of instruments would you fit, and which number backs that up?
Name one thing this model does not tell you about real instruments.
Revisit the mission evidence
Formative · not an official grade
No formative evidence has been recorded yet.
Next: Write your prediction, run both set-ups, then pick the evidence that supports your answer.
Formative guidance only. Official grade: none. A teacher still reviews your written reasoning.