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First known 'disappearing planet' has a neighbor that makes it wobble like a top

from Phys.org

UCLA-led astronomers have discovered the first known "disappearing planet" about 1,000 light-years away. The planet, TOI-2535 b, is a "hot Jupiter," a gas giant that orbits extremely close to its host star. TOI-2535 b whips around its star in only 8.25 days—10 times faster than the 88 days that Mercury takes to go around our sun once.

explained

An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first detected in 1988, was confirmed in 2003. In 2016, it was recognized that the first possible evidence of an exoplanet had been noted in 1917, a precovery. As of 5 November 2026, there are 6,464 confirmed exoplanets in 4,849 planetary systems, with 1,074 systems having more than one planet.

There are many methods of detecting exoplanets. Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of large planets close to the star. About 1 in 5 Sun-like stars are estimated to have an "Earth-sized" planet in the habitable zone. Assuming there are 200 billion stars in the Milky Way, it can be hypothesized that there are 11 billion potentially habitable Earth-sized planets in the Milky Way, rising to 40 billion if planets orbiting the numerous red dwarfs are included.

From Wikipedia: Exoplanet (CC BY-SA 4.0) ↗
how it works

A gravitational tug from a second body slowly twists the planet's orbital plane, a process called precession. Transits are only visible when the orbit is edge-on to us, so as the plane tilts away, the dimming stops.

so what

It shows that a planet's absence in survey data doesn't always mean it isn't there. Some of the planets that seem to be missing may be hidden by changing orbital geometry, and a wobbling orbit also reveals an unseen companion.

fun fact

Hot Jupiters were a shock when the first was found in 1995, because gas giants of that size were expected to form far from their stars.

more on this

Illustrative photo · ESO/M. Kornmesser, CC BY 4.0, via Wikimedia Commons