Stargazing this Week
Stargazing will be great this weekend with Saturday’s new moon keeping our skies dark. There’s a lot of action happening around sunset for the next few days, and the darker skies are a welcome assist. In particular, there’s a comet to be found!
Comet C/2021 O3 (PanSTARRS)
The comet C/2021 O3 (PanSTARRS) may be visible with binoculars on the Northwestern Horizon around 8:15p - or just after sunset. C/2021 O3 is a non-periodic comet, meaning it’s probably a one-time visitor to our solar ssytem. As its closest approach to the sun was estimated around 30% of the Earth’s distance (0.29 AU) on April 21st, there was some concern it might burn up before we could see it.
Astronomy Magazine reported that it was still there as a few days ago - observed at magnitude 11. From our perspective on earth, it should be brightening up as it recoils away from the sun - possibly below magnitude 6 - which could make it visible through a pair of binoculars.
C/2021 O3’s trajectory puts it rising thought he constellation Perseus as the week wears on.
In the winter, Perseus is easy jump to from Orion and the Pleiades. Nowadays, Orion is setting just as the sun does. The hoop of stars that form the cancellation Auriga or the “W” shape of Cassiopeia flank the twig-like Perseus constellation, all of which can be found on the NW horizon at sunset.
Mercury and the Waxing Crescent
Since you looking that way, the Pleiades will set just as the Sun does, and the planet Mercury will hover nearby that famous star cluster for most of the week. The faint, waxing crescent moon will also be present. You can use both to anchor yourself to find C/2021 O3 at least through the first of May, when the comet the moves straight up through Perseus.
The label PanSTARRS refers to the collaboration of astronomers and telescopes known as the “Panoramic Survey Telescope And Rapid Response System”. It is not the name of the comet. PanSTARRS scans the night sky to look for transient or variable objects, like comets or supernovae. This was point of confusion even amongst the stargazing professionals back in 2013 with the comet C/2011 L4 that was also attributed to PanSTARRS.
A Breakfast Pairing
If you’re up early for adventure this weekend, look to the Eastern horizon. The array of planets are all still present, but this weekend, Venus and Jupiter will appear to be right on top of one another. Together their joint brightness will make them very obvious in the sky, a perfect pair to pair with an early cup of coffee. Saturday sometime after 4:30a is probably your best time for a view
Stargazing notes brought to you each week by the the Methow's own Pasayten Institute, an organization on a mission to build and share physics knowledge, without barriers. Star charts generated on stellarium, an open access program. Try them out at stellarium-web.org.
