TESS will be mostly limited to finding planets that orbit their stars very quickly - in a few weeks or less.

• A. It will focus on long-period planets
• B. It will observe only distant stars
• C. It will primarily find planets that orbit quickly
• D. It will not detect any short-period planets

Answer: (C)

Planets detected by the transit method depend on watching for repeated dips in a star’s light as a planet passes in front. TESS observes each patch of sky for about 27 days at a time, and to confirm a planet you typically need to see multiple transits. Planets with short orbital periods complete many orbits in that window, so their transits happen frequently and are easy to spot and confirm. Longer-period planets may only show a single transit during a sector, making it much harder to distinguish a true planet signal from noise. Because of this observing pattern, the mission is most effective at finding planets that orbit quickly. The other statements don’t fit: TESS targets bright, relatively nearby stars; it isn’t limited to distant stars; and it does detect short-period planets.