Measurements of this interstellar comet’s molecular makeup show an excess of heavy water molecules that is dramatically ...

Scientists are grappling with a cosmic mystery: why does the Universe behave differently on massive scales compared to our ...

Rather than slowly condensing over millions of years, the first building blocks of Earth and other planets may have formed ...

The workings of our solar system are roughly the same now as they have been for millions of years. Moons circle their planets, the planets circle the sun, the sun’s magnetic fields and sunspots wax ...

Gravity, electromagnetism, the strong nuclear force, the weak nuclear force. For decades, physicists have recognized exactly ...

Far from the Sun’s heat, orbiting the outer planets of the solar system, are moons with oceans of liquid water beneath their frozen surfaces. Keith Cooper finds out how planetary scientists are ...

Our solar system is a smashing success. A new study suggests that from its earliest period — even before the last of its nebular gas had been consumed — Earth’s solar system and its planets looked ...

Easy: Venus is the weirdest planet in the solar system. The most distant major planet from the sun and the last stop before ...

Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...

Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory about the possibility of a giant ninth planet. The dwarf planet's existence ...

NPR's Ari Shapiro talks with astronomer David Jewitt about what we can learn from the third interstellar object to have entered our solar system, a comet-like object known as 3I/ATLAS. A remarkable ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...