Earth's Place in the Universe
- Space
A passing star could fling Earth out of orbit — or into the sun
Computer models show that a star's tug could send Mercury, Venus or Mars crashing into Earth — or let Jupiter eject our world from the solar system.
- Space
Scientists Say: Quasi-satellite
Unlike a true satellite, these tagalongs orbit outside a planet’s primary sphere of gravitational control.
- Planets
A giant, busted planet fuels a nebula’s mysterious glow
This Helix Nebula is like a colorful explosion frozen in time. Its center seems to be steadily radiating X-rays.
- Earth
Scientists Say: Caldera
These gigantic craters form when a volcanic eruption empties magma chambers underneath, allowing the mountain to crumble into the void.
- Space
A nearby star system is likely sending lots of comets our way
This Alpha Centauri system loses comets and dust particles, but it produces only about 10 of the several trillion meteors that Earth sees each year.
- Space
Scientists Say: Interstellar medium
Radiant energy and primordial space dust span the vast reaches between star systems.
- Chemistry
Micro-sparks between water droplets may have started life on Earth
This micro-lightning can drive chemical reactions that produce compounds needed for the natural formation of life on Earth, experiments show.
- Planets
Pluto and its moon Charon may have paired up with a kiss
After about 30 hours of contact, Charon could have separated from Pluto and drifted into its current orbit.
- Planets
A distant crumbling planet spills its guts
Based on the light being emitted by its shed minerals, astronomers can for the first time determine the internal composition of an exoplanet.
- Planets
So many wondrous moons — just a spaceship ride away
Scientists are studying extraterrestrial moons for clues to how planets form, how life began — and whether there’s life out there right now.
- Space
Ancient black holes might solve the mystery of dark matter
Studies of gravitational waves, stars and other features of the universe could reveal whether such “primordial” black holes exist.
- Space
This zombie star’s spiky filaments are baffling astronomers
The star's odd tendrils were somehow formed by a supernova that skywatchers saw way back in 1181.
