What did you change in the model?
Labs / Astronomy
Parallax Distance Finder
As Earth swings from one side of its orbit to the other, a nearby star appears to slide back and forth against the far-off background. Drag Earth around its orbit and set the star's true distance — the tinier the wobble, the farther the star. The half-angle of that wobble, measured over a one-astronomical-unit baseline, is the parallax, and its distance in parsecs is simply 1 divided by that angle.
Labs / Astronomy / Parallax Distance Finder
Parallax Distance Finder
As Earth swings from one side of its orbit to the other, a nearby star appears to slide back and forth against the far-off background. Drag Earth around its orbit and set the star's true distance — the tinier the wobble, the farther the star. The half-angle of that wobble, measured over a one-astronomical-unit baseline, is the parallax, and its distance in parsecs is simply 1 divided by that angle.
Why it matters
Why explore this?
Astronomy uses patterns in light and motion to explain objects we cannot touch directly. This model lets you change one part of a space system and see what the evidence would look like.
Explore
Try the model
shift +0.000″p 0.379″base 0.00 AUd 2.64 pc8.6 ly
Investigate
Questions to test
Predict first, try it in the model, then use what you observe to answer.
What to try
- Push the star out to 12 parsecs. What happens to the size of its apparent shift in the sky view?
- The parsec is defined by a parallax of exactly one arcsecond — at what distance does that happen here?
- If you could only measure angles down to 0.01″, how far away could you still reach with parallax?
- Why does the shift shrink to zero when Earth is at the top or bottom of its orbit, and peak at the sides?
- Proxima Centauri and Vega are both preset here — how many times larger is Proxima's parallax angle?
Explain
Make sense of what happened
Look for a cause-and-effect rule: what did you change, what responded, and what stayed the same? Astronomers use those patterns to infer how distant systems work.
Check
Before you leave
What visible evidence changed?
What rule could explain that change?
If you can answer all three using evidence from the model, you understand the main idea. If not, return to Explore and change one setting at a time.