Perihelion: 1985 September 5.21, q = 1.028 AU  The last comet discovered in the 19th Century was found on December 20, 1900, by the French astronomer Michel Giacobini from Nice Observatory, the fifth of twelve comets he discovered between 1896 and 1907. The comet was around 10th magnitude and was followed for two months, with …

A common and persistent theme throughout “Ice and Stone 2020,” and indeed one of the primary reasons the “small bodies” of the solar system are of such high interest in the first place, is the threat they pose to Earth – or, at least, to our civilization and way of life here on Earth – …

As the Boeing team continues to implement hardware and software changes recommended by the joint review team, NASA’s Commercial Crew Program is targeting December for the launch of a second uncrewed test flight of the Boeing CST-100 Starliner spacecraft to the International Space Station.  “The Commercial Crew Program currently is targeting no earlier than December …

This is a challenging time for families. Schools across the U.S. are struggling to provide a meaningful online experience. The coronavirus pandemic has cut off or restricted many entertainment options. As an astronomer, I believe a great way for families to fill the void and have a meaningful science experience in the time of COVID-19 …

SEPTEMBER 6, 1618: The German astronomer and mathematician Johannes Kepler observes Comet 1618 I (new style C/1618 Q1) – the first of three “Great Comets” that appeared that year – through a small telescope, the first recorded telescopic observation of a comet. SEPTEMBER 8, 1991: Tom Gehrels with the Spacewatch program in Arizona discovers the …

Perihelion: 2019 August 8.55, q = 2.007 AU  According to our present understanding of how the solar system formed and evolved, all the various comets, including those passing through the inner solar system as well as those in the Kuiper Belt and the Oort Cloud, are the “leftovers” from the planet formation process. Over the …