Researchers from Japan and the Netherlands who were previously involved in the discovery of an exoplanet with huge rings have now calculated that the giant rings may persist more than 100,000 years — as long as the rings orbit in the opposite direction compared to that of the planet around the star.
Halley’s Comet, officially designated 1P/Halley, is visible from Earth every 75–76 years. Despite this regular return, the comet’s orbit cannot be predicted exactly due to processes inside the comet and its chaotic interaction with the planets and minor bodies in the solar system. A team of Dutch and Scottish researchers has now found an explanation for the chaotic orbital behaviour of 1P/Halley.
The chemical element lithium is predicted to have been created by the Big Bang, 13.8 billion years ago. Observations of Nova Centauri 2013 show that lithium has been found for the first time in material ejected by a nova, helping to explain the mystery of why many young stars seem to have more of this chemical element than expected.