All week – Comet NEOWISE dims
After putting on an exciting show for a couple of weeks, Comet C/2020 F3 NEOWISE has passed Earth on its way back out of the Solar System – perhaps to return in about 6,000 years (space is big!). The comet’s increasing distance from Earth and the continuous reduction in heating from the Sun are causing NEOWISE to fade in brightness over time. I’m not saying that you can’t see it anymore — it’s just a lot harder now. It will be visible in binoculars and telescopes for another couple of weeks, and then become a telescope-only target after about mid-August.
See “Comet NEOWISE dims to binocular object” for more on where and how to find the comet.
Tuesday, July 28 pre-dawn – Southern Delta Aquariids Meteor Shower peaks
The Southern Delta Aquariids meteor shower runs annually from July 21 to August 23. It will peak before dawn on Tuesday, July 28, but it is quite active for a week surrounding that date. This shower, produced by debris dropped from Comet 96P/Machholz, commonly generates 15-20 meteors per hour at the peak. It is best enjoyed from the southern tropics, where the shower’s radiant, in southern Aquarius, is positioned higher in the sky. The waxing gibbous Moon on the peak date will set in early evening, so it should not adversely affect pre-dawn views of the shower.
Friday, July 31 pre-dawn – Venus near the Ruby Star
When the very bright planet Venus rises in the east at around 3 a.m. local time on Friday, July 31, it will be positioned less than a finger’s width to the upper left (or 0.6 degrees to the celestial north) of the Ruby Star. That star, also designated 119 Tauri and CE Tauri, is a giant, aging, pulsating variable star that shines with a deep red color. The pair will be visible in binoculars and backyard telescopes (red circle) until the sky begins to brighten. (Note that your telescope will likely flip and/or mirror this view.) You’ll need to look closely to see the ruby. At magnitude -4.55, Venus will outshine the magnitude +4.3 star by a factor of nearly 3,500!
Saturday, August 1 all night – Bright Moon below Jupiter and Saturn
The Moon’s monthly visit with the gas giant planets Jupiter and Saturn will happen on the night of Saturday, August 1. Shortly before dusk, the trio will rise together over the southeastern horizon, with the Moon positioned directly below (or to the celestial south of) bright Jupiter. The Moon and Jupiter will fit into the field of view of binoculars (red circle). As they cross the sky during the night, the Moon will creep east, towards dimmer Saturn, and the diurnal rotation of the sky will move Jupiter below the Moon. This conjunction will make a beautiful wide field image in early evening (or in the southwestern sky around 3 a.m. local time), especially when composed with some interesting foreground scenery.
Chris Vaughan is a science writer, geophysicist, astronomer, planetary scientist and an “outreach RASCal.” He writes Astronomy Skylights, and you can follow him on Twitter at @astrogeoguy. He can also bring his Digital Starlab portable inflatable planetarium to your school or other daytime or evening event. Contact him through AstroGeo.ca to tour the universe together.