Newly discovered asteroid (IMAGE) Carnegie Institution for Science Caption An artist’s conception of the newly discovered asteroid 2021 PH27, which has the shortest known orbital period for an asteroid and second shortest for any object in our Solar System after Mercury. Illustration by Katherine Cain courtesy of the Carnegie Institution for Science. Credit Illustration by Katherine Cain courtesy of the Carnegie Institution for Science. Usage Restrictions With credit License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.