Indus

By BrightK self-checked Published 2026-09-04 Updated 2026-10-18 Editorial policy

• Constellations
• In the sky now

What is Indus?

Constellations· Southern spring · between Grus and Pavo. Indus is a southern constellation that grew out of observations by Dutch navigators in the late 16th century. It has few bright stars, but beside Epsilon Indi, a neighbour star about 12 light-years away, two brown dwarfs and a planet heavier than Jupiter have been found.

Stars of the figure

The 2 brightest of the 2 stars used in the figure (1 lines). Lower magnitude means brighter.

Constellation basics

Figures are representative approximations. Source: compiled from NASA and IAU public data.

Epsilon Indi's planet, photographed by the Webb telescope

Hints of a planet around Epsilon Indi appeared in the early 2000s. Astronomers saw the star wobble very slightly as a planet tugged on it, and the planet was confirmed in 2018. It is called Epsilon Indi Ab. Then in 2023 the James Webb Space Telescope photographed the planet directly, and the results were announced in 2024.

The planet in the image is a giant about six to seven times the mass of Jupiter. It orbits about 30 AU from its star, roughly the distance from the Sun to Neptune. Its temperature is only about 2 degrees Celsius, very cold. However, its position and mass in the image did not match what earlier measurements had predicted. So astronomers had to work out its orbit again.

Planets photographed directly are usually young and hot enough to glow on their own. Epsilon Indi Ab is much older and colder, which makes it a rare chance to study an old giant planet much like Jupiter in our own solar system. The observation was possible because the star is so close, only about 12 light-years away.

The constellation in depth

Indus is one of twelve southern constellations based on stars observed by the Dutch navigators Pieter Keyser and Frederick de Houtman on their way to the East Indies in the 1590s. It became widely known when it appeared in Johann Bayer's star atlas of 1603. It was drawn as a native man holding spears and arrows, but which people it was meant to show was never clearly recorded.

Its brightest star, Alpha Indi, is an orange giant of magnitude 3.1. The star that draws the most attention, though, is Epsilon Indi, at magnitude 4.7. It is a close neighbour about 12 light-years away, an orange star a little smaller and cooler than the Sun. Far out from it, a pair of brown dwarfs, objects too light to become true stars, orbit together around it.

Epsilon Indi also moves quickly across the sky. It shifts by about 4.7 arcseconds a year, a large motion for a star visible to the naked eye. That is a tiny angle, so no one can notice it from day to day, but over thousands of years its position changes visibly. Being close and fast-moving, it was put on lists of nearby stars early on.

Indus lies deep in the southern sky, so from New York only Alpha barely touches the southern horizon, and from London none of it rises; in practice it cannot be seen from mid-northern latitudes. From the southern hemisphere it rides high on September and October evenings as a long triangle between Grus and Pavo. In the Sky view, choose Sydney or Cape Town on an October evening to see the triangle made by its three stars.

Frequently asked

When can I see Indus?

Indus is best seen in Sep–Oct evenings; only its northern tip grazes the horizon from New York; not visible from London.

How do I find Indus?

To find Indus, look for a long triangle southwest of Grus and east of Pavo.

What is the brightest star in Indus?

The brightest star in Indus is The Persian, at magnitude 3.1.

Related

Figures are representative approximations. Simulated positions use J2000 mean elements.