SLOP3255 · Week 02 · Provenance
From telescope to speaker#
A sonification is only as trustworthy as the chain of decisions behind it.
A telescope does not hand us meaning#
The “raw data” already belongs to an instrument, a place and a measurement protocol.
The complete route#
Each stage changes the object. Provenance is the record of those changes.
Calibration is not cosmetic#
| Correction | Problem addressed | If omitted |
|---|---|---|
| Bias / dark | electronic offset and thermal signal | baseline drifts upward |
| Flat field | uneven pixel sensitivity | position looks like brightness |
| Reference star | changing atmosphere | cloud can resemble a transit |
| Time standard | clock and location differences | events cannot be aligned |
Calibration makes comparison possible; it does not make the result neutral.
Preparation and presentation are different layers#
Scientific preparation
- calibration
- quality flags
- background subtraction
- derived quantities
Auditory presentation
- window selection
- normalisation
- mapping range
- playback speed
Document both layers, because they answer different questions.
A minimum provenance record#
| Field | Example entry |
|---|---|
| Source | institution + dataset identifier + retrieval date |
| Selection | object, channel, time interval, exclusions |
| Operations | calibration, filtering, filling, normalisation |
| Mapping | input units and output range for every sound dimension |
| Software | tool, version and reproducible parameters |
Another person should be able to retrace the route without guessing.
The polished-output trap#
Beautiful but opaque
A smooth melody, no units, no missing values and no description of filtering.
The listener cannot separate signal from design.Inspectable
Audio beside values, plot, operations and a plain-language claim.
The experience survives scrutiny.What single missing field would most change your interpretation?
Worked case: a small transit study#
The sonification should receive the calibrated target/reference ratio, not arbitrary camera brightness. Its legend names that distinction.
Reference workflow: NASA Exoplanet Watch
Listening Lab 02 · Output: provenance diagram
Reassemble the chain#
Task
Put twelve shuffled operations between telescope and speaker. Mark each as measurement, calibration, reduction or presentation.
Test
- every arrow has an owner
- units survive each stage
- one uncertainty is visible
Reference: NASA Exoplanet Watch · science.nasa.gov/citizen-science/exoplanet-watch/