Science Daily: Cometary Impact on Neptune: Herschel Data Point to Collision About Two Centuries Ago.
ScienceDaily (July 21, 2010) — A comet may have hit the planet Neptune about two centuries ago. This is indicated by the distribution of carbon monoxide in the atmosphere of the gas giant that researchers -- among them scientists from the French obser-vatory LESIA in Paris, from the Max Planck Institute for Solar System Re-search (MPS) in Katlenburg-Lindau (Germany) and from the Max Planck Insti-tute for Extraterrestrial Physics in Garching (Germany) -- have now studied. The scientists analyzed data taken by the research satellite Herschel, that has been orbiting the Sun in a distance of approximately 1.5 million kilometers since May 2009.
The research is published in Astronomy & Astrophysics (July 16, 2010).