If any clear skies occur during the last week of October, don’t miss any opportunities to view a 700-metre-wide space rock with the catchy designation 162082 (1998 HL1) as it hurtles past our planet slightly more than sixteen lunar distances away at 17:20 UT (6:20pm BST) on 25 October 2019.
Predicted to reach a peak magnitude of +12.4 on 27 October, this near-Earth asteroid is a viable target for 6-inch (15-cm) aperture telescopes and larger for five nights as it zips through the constellations of Triangulum, Aries and into Cetus at rates of up to 9 degrees/day relative to the background stars. (See the bottom of this page for a table of predicted positions at hourly intervals for observers in the UK and Western Europe.)Although classified as a Potentially Hazardous Asteroid (PHA), there is no chance that 1998 HL1 could collide with Earth for at least 120 years. The next time it passes closer to Earth than this apparition is on 26 October 2140 when it zips by our planet at a distance of 6.18 million kilometres, or 3.8 million miles.Discovered by the Lincoln Near-Earth Asteroid Research (LINEAR) project at Socorro, New Mexico on 18 April 1998, 162082 (1998 HL1) is an Apollo-type asteroid that loops the Sun once every 508 days in an eccentric orbit inclined by 20 degrees to the ecliptic.
At 9:24am GMT on 31 October 2016, near-Earth asteroid 164121 (2003 YT1) will safely fly by at a distance of 3.2 million miles (5.2 million kilometres), or 13.5 times the distance of the Moon. Furthermore, this 1.1-mile-(1.7-kilometre)-wide Apollo asteroid also passes very close to Polaris early on 2 November, creating a rare astrophotographic and observing opportunity.
Mercury attains a greatest easterly elongation of 19 degrees from the Sun on 1 April. This solar separation combined with a favourable inclination of the ecliptic to the western horizon an hour after sunset, means that the period 25 March to around 8 April offers the year’s best evening showing of the innermost planet for Northern Hemisphere observers.
Ever since it was realised that asteroid and comet impacts are a real and present danger to the survival of life on Earth, it was thought that most of those objects end their existence by plunging into the Sun. But a new study finds instead that most of those objects are destroyed in a drawn out, long hot fizzle, much farther from the Sun than previously thought.