Survive the dark side.
Every orbit, your spacecraft passes behind the Earth. For that stretch there is no sunlight, no power from the panels, and everything has to run off the battery. Your team will send two different spacecraft through the same shadow and work out which one comes through it in better shape.
When the Sun disappears, which spacecraft copes better - and how would you know?
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 calculate the difference between the energy each spacecraft generated and the energy it consumed, and demonstrate this by reporting both differences with units.
- 02By the end of this mission, the learner will be able to model why using more energy than is generated over one orbit does not necessarily mean the mission fails, and demonstrate this by relating that difference to the battery reserve remaining.
- 03By the end of this mission, the learner will be able to test whether the lowest bus voltage stays within a stated operating limit, and demonstrate this by comparing both voltage minima against that limit.
Before we start
A quick check of what you already know. There is no score.
The idea behind the mission
Two spacecraft, the same orbit, the same shadow. Only the spacecraft is different, so anything that changes is caused by the spacecraft.
No sunlight, no new energy
Solar panels only work in sunlight. Behind the Earth there is none, so for that part of every orbit the spacecraft spends stored energy and makes none. The battery has to be big enough to carry everything through the dark, and still have something left.
Predict before you run
Before you run anything: which spacecraft do you think will have more charge left after the shadow, and why?
Which spacecraft will have more charge left when it comes out of the shadow - 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
Small satellite (1U)
Candidate case
Larger satellite (3U)
- Write your prediction first.
- Send both spacecraft through the same shadow, so the only difference is the spacecraft itself.
- The battery, voltage and temperature numbers come from a model, not from a real spacecraft.
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
Send the small satellite through first, then the larger one. Same orbit, same shadow, same length of time.
Baseline
Small satellite (1U)
Candidate
Larger satellite (3U)
Run the baseline first so you have something to compare against.
Read the evidence
Look at where the battery falls and where it recovers. The shaded band on the chart is the time in shadow.
Run the Twin to produce evidence.
Make the engineering decision
Which spacecraft would you send, and which number in your evidence supports that?
Which spacecraft do you recommend for a mission that must survive the shadow?
What this does not prove
What this mission shows
- My prediction
- The battery and temperature comparison between the two spacecraft
- Where each number came from
- One thing this model does not cover
What it does not establish
- The battery, voltage and temperature numbers are produced by a model. Nothing here was measured on a real spacecraft.
- The two spacecraft are teaching profiles, not real hardware designs.
- This lesson does not show that either design would survive a real mission, and it is not evidence that a design is ready to fly.
Name one thing this model does not tell you about how a real spacecraft would cope.
Show what you understood
Formative feedback for you and your teacher. There is no official grade.
Why does the battery level fall while the spacecraft is in shadow?
Which pair of numbers shows whether a spacecraft is living within its energy budget?
Which spacecraft would you send on a mission that must survive the shadow, and which number backs that up?
Name one thing this model does not tell you about how a real spacecraft would cope.
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.