New York’s asteroid hunt

NEW YORK CITY is used to feeling  at the centre of the world and this week the city of 8 million became the nucleus of the latest asteroid hunt. New Yorkers weren’t panicked: the 72-kilometre-wide asteroid Erigone wasn’t about to smash into the city. Rather, it was scheduled to eclipse Regulus – the brightest star in the constellation Leo – as seen from the Big Apple and parts of eastern North America. As New Scientist went to press, this “occultation” was set to make Regulus vanish for 14 seconds at around 2 am on 20 March. Asteroid occultations are a common astronomy tool. Reporting whether an occultation was visible  at various points, and for how long, leads to more precise ideas of the sizes and paths of space rocks.
However, such events are usually  only seen with a telescope, from dark corners of the globe. The Erigone occultation should have been visible to millions of people, with the naked eye, through the lights of Manhattan. The International Occultation Timing Association (IOTA) plans to exploit this, and has asked volunteers to send in reports if they saw it. One question the group hopes to answer is whether Erigone has a satellite. Even if the occultation is a miss for parts of NYC because Erigone deviated from its predicted path, knowing that will be useful, says IOTA’s Brad Timerson. Planned NYC occultation parties  are a novelty for his community, which usually spreads out to maximise the data’s scope. “Occultation timers are kind of loners in that regard,” he says.