Jupiter‑Sized Exoplanet Discovered Orbiting a Sun‑Like Star

It’s not every day that a planet the size of Jupiter shows up around a star that looks a lot like our own Sun. Yet that’s exactly what a group of astronomers announced this week – a fresh find that could help us piece together how giant worlds form and evolve.

The planet, dubbed NGTS‑39 b, was spotted by a collaboration headed by Ioannis Apergis at the University of Warwick. The team combined data from the space‑based TESS mission with follow‑up observations taken on a dozen ground‑based Newtonian telescopes. In other words, they used a little bit of high‑tech satellite eye‑watching and a lot of good‑old Earth‑bound stargazing to nail down the signal.

What they found is a world that’s a shade larger than Jupiter – about 1.09 times Jupiter’s radius – and heftier, weighing in at roughly 1.47 Jupiter masses. It whizzes around its host star every 58.2 days, which means a year on NGTS‑39 b is less than two Earth months. Temperatures hover around 519 K, warm enough to keep hydrogen and helium in a gaseous state, which is exactly what the researchers think makes up most of its bulk.

The host star, fittingly called NGTS‑39, isn’t a perfect twin of our Sun, but it’s close. It’s about 16 % larger and a bit more massive, and astronomers estimate it’s around 2.2 billion years old – a cosmic teenager compared with the Sun’s 4.6 billion years. Its Sun‑like nature makes the system a valuable laboratory for testing theories about gas‑giant formation around stars that aren’t too different from ours.

There’s also a hint of something else lurking in the system. Subtle variations in the data suggest a possible second planet, though the evidence isn’t solid enough yet. Future observations, perhaps with the upcoming James Webb Space Telescope or more precise radial‑velocity measurements, will be needed to confirm whether there’s an additional world sharing the stage.

All told, NGTS‑39 b adds another data point to the growing catalog of giant exoplanets and reminds us how much variety there is out there. Each new discovery, big or small, nudges our understanding of planetary systems a little further – and who knows? Maybe one day we’ll find a Jupiter‑sized neighbor that’s a little more Earth‑friendly.