Impossible Worlds: Planets That Shouldn't Exist But Do"

In the vastness of space, some planets defy the very rules of planet formation. Recently, astronomers discovered strange and seemingly impossible worlds that are making scientists question their understanding of how stars and planets form and evolve. Let’s dive into these mind-bending discoveries.

The Mysterious LHS 3154 B

Orbiting a dim, tiny star nine times smaller than our Sun, LHS 3154 B should not exist. The planet is massive—13 times heavier than Earth and similar in size to Neptune. Normally, such a small star wouldn’t have enough gravitational pull to gather the material necessary to form a planet this large. Planets usually form through core accretion, a process where dust and gas come together bit by bit to create a solid core that attracts more material over time.

This star, however, shouldn’t have had a large enough disc to make such a heavy planet. The discovery of LHS 3154 B, just 50 light-years away in the Hercules constellation, is forcing scientists to rethink planet formation theories. One new idea, gravitational instability, suggests that instead of gradual formation, the entire gas disc could have collapsed at once to create the planet. Even with this theory, though, LHS 3154 B remains a puzzling anomaly.

Halla: The Forbidden Planet

Another planetary mystery is Halla, which orbits a star named Baekdu. According to current theories, Halla should have been destroyed. When stars like Baekdu expand into red giants, they usually engulf or obliterate nearby planets. Yet, Halla somehow survived, challenging everything astronomers know about planetary survival near dying stars.

Scientists have two theories about Halla’s survival:

Stellar Merger – Baekdu could have been two stars—a white dwarf and a red giant—that merged, preventing the red giant from expanding enough to destroy Halla.

Post-Merger Formation – Halla may have formed from debris left .

BAt 268 light-years away, LTT 9779 B has a reflective surface that makes it one of the shiniest planets ever found. It reflects 80% of the light from its star—similar to how a mirror reflects light. This neptune-sized world is alarmingly close to its star, completing one orbit in just 19 hours. With temperatures soaring to 3,600°F (1,982°C), planets this close usually lose their atmospheres and turn into barren rocks.

LTT 9779 B, however, holds onto its atmosphere thanks to its metallic clouds made of glass and titanium salt. These clouds act like a shield, reflecting heat and preventing the planet from overheating. While visually stunning, this harsh, reflective world is far from hospitable.

The James Webb Space Telescope has also revealed WASP-107 B, a planet with an atmosphere so light and thin that it resembles a fluffy comet. Located about 208 light-years away in the Virgo constellation, this "super-Neptune" is about the same size as Jupiter but far less dense. It orbits its star in just six days, experiencing intense ultraviolet radiation that causes it to gradually lose its atmosphere, forming a comet-like tail.

Interestingly, WASP-107 B contains silicate clouds—clouds made of fine sand-like particles. These clouds condense, fall, and vaporize in the planet’s scorching layers, creating a strange cycle. The planet’s low density allows light to penetrate deep into its atmosphere, generating sulfur dioxide, a gas that smells like burning matches. Scientists believe WASP-107 B didn’t originally form so close to its star but was drawn inward .

These discoveries are reshaping our understanding of planet formation and survival. Each of these planets—LHS 3154 B, Halla, LTT 9779 B, and WASP-107 B—challenges what we thought we knew about the rules governing the universe. From planets forming under impossible conditions to surviving in hostile environments, these rule-breaking worlds offer a glimpse into the complexity and unpredictability of the cosmos.