The planet with the least circular orbit is Mercury, which has an orbital eccentricity of 0.2056. Its orbit brings it to within 46,001,200 km (0.307 AU) of the sun at its closest point (perihelion) ...

Comets can supply volatile and prebiotic material to rocky planets, but survival of fragile molecules depends on atmospheric entry and impact.

Long-term fluctuations in the intensity and inclination of the Earth’s magnetic field could arise from variations in the eccentricity of our planet’s orbit, according to Japanese geophysicists.

Earth’s annual orbit around the Sun is not always perfectly circular; instead, it displays variations in what is known as eccentricity — in which the planet’s orbit varies between a more-circular and ...

This artist’s impression shows a Jupiter-like exoplanet that is on its way to becoming a hot Jupiter — a large, Jupiter-like exoplanet that orbits very close to its star. NOIRLab/NSF/AURA/J. da Silva ...

These two curves show the final distribution of orbit shapes for giant planets and brown dwarfs. The orbital eccentricity determines how elongated the ellipse is, with a value of 0.0 corresponding to ...

The first exoplanet ever discovered in 1995 was what we now call a "hot Jupiter," a planet as massive as Jupiter with an orbital period of just a few days. Today, hot Jupiters are thought to have ...

In an analysis of the past 1.2 million years, a geologist examining ocean sediment cores has discovered a pattern that connects the regular changes of Earth's orbital cycle to changes in the Earth's ...

The world is currently experiencing the Ice Age called the Quarternary period. There have been five ice ages since the planet was born. Each of them was characterized by periods of lower temperatures ...