Chart assignment

Charts to read and discuss

Read each chart, then answer its questions. Every chart shows its source and date; open it for a table of the numbers and the data to download.

  1. How do astronomers find planets around other stars?

Chart 1 of 1 · Space

How do astronomers find planets around other stars?

The interactive chart needs JavaScript. The numbers are on the chart's page.

As of November 2026, 4,785 of the 6,451 confirmed exoplanets, about 74%, were found by the transit method: a telescope sees a star dim slightly as a planet passes in front of it. Radial velocity, which spots a star's slight wobble as a planet tugs on it, found 1,204. Only 98 have been photographed directly (imaging).

Questions to discuss

  1. In one sentence of your own, what does this chart show?
  2. Find the biggest change or difference in the chart. What might explain it?
  3. Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?

Source: NASA Exoplanet Archive, Planetary Systems Composite Data (Public domain (NASA data); this research has made use of the NASA Exoplanet Archive, operated by Caltech under contract with NASA) · Data as of Nov 4, 2026

Open the chart and its numbers

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