Deep Space Course

Learning observatoryDeep Space Course

Mission control Course map Lessons Labs Practice Journal Settings

Field rule

What was measured? Which model connects it to the claim?

Acquiring signal

All investigations

Interactive laboratory

Read a Star with Linear Algebra

How does a spectrum reveal composition?

Fit absorption features, inspect residuals, and see how blending makes an inference unstable.

Spectrograph controls

Measurement noise0.008Line separation8.00 nmFeature A depth0.14

Predict before moving the control

Move the features together. The combined dip remains visible—but can the fit still tell which component caused it?

Fit A

0.1412

Fit B

0.2414

Residual σ

0.0078

Condition

1.0

Continuum-normalized spectrum

The orange forward model is fitted to the noisy cyan measurement.

Residual structure

Download Python notebook