Comets, asteroids and other Near-Earth Objects (NEOs) are a fascinating sight to behold, if you can manage to spot one in the night sky.
Many will remember the appearance of Comet Hale-Bopp in the 1990s, or much more recently, the beautiful sight of Comet NEOWISE that made headlines around the world and enticed us all to take a look up at the evening sky.
Asteroid Vesta, for example, is one member of the Asteroid Belt that can also be seen, provided you know where and when to look.
But how do you spot comets and asteroids in the night sky? Find out in our guide below which comets and asteroids are visible tonight and over the coming weeks.
June 2021: See Asteroid 30 Urania
Asteroid 30 Urania was discovered by the English astronomer John Russell Hind on 22 July 1854. It reaches opposition on 14 June 2021, when it can be located against the stars of the constellation of Ophiuchus, the Serpent-bearer.
Urania is a main belt asteroid. Its shape and dimensions were measured using a technique known as speckle interferometry, which revealed the asteroid to be elliptical with a longest dimension of 111km and narrowest of 89km.
At its brightest it can be mag. +9.4, so this opposition doesn’t present it at optimal brightness. It takes 3.64 years to orbit the Sun, an orbit that takes it out as far as 2.67 AU and as close as 2.07 AU.
Urania is an S-type or siliceous asteroid, a class that has a stony or mineralogical composition. S-type asteroids account for about 17% of asteroids.
Strictly speaking Urania starts the month in Sagittarius, the Archer, 2˚ north of mag. +4.2, 3 Sagittarii. This positions it very close Sagittarius’s western border and tracking west.
It’s not long before Urania crosses this invisible demarcation line, slipping into Ophiuchus in the early hours of 3 June.
Urania remains above or equal to mag. +11.0 all month, a viable target for a small telescope, but beyond average binocular range.
Its track this month takes it 2˚ south of the mag. +7.4 globular cluster NGC 6401 on the nights of 6/7, 7/8 and 8/9 June.
It passes 0.5º south of mag. +3.3 Theta (θ) Ophiuchi on 22/23 June.
By the month’s end, it’s located 4˚ east-northeast of the mag. +6.8 globular cluster M19. The bright skies found near the June solstice will make locating even a mag. +11.0 object trickier than normal.
Pete Lawrence is an experienced comet and asteroid observer and a co-host of The Sky at Night.