Bakersfield Night Sky — July 18, 2026
Whew! I finally finished the updates to my Astronomy Notes textbook. It’s been a six-month project. With its completion, I can now enjoy my summer break! Please take a look at astronomynotes.com . The structure has been stable for the past 25+ years, so links to any of the pages within have worked all that time while the content on the pages have been updated. I’ve seen Adobe Flash come and go on the web and the gif animations I created long ago still work fine on all browsers. I’ve also seen two or three iterations of the NASA, NOAO, NRAO, ASP, and other astronomy institution websites with the many broken links that come with their updates.
One thing that has been a bit distressing about those other institution website updates is that some really good and still valid material has vanished—been deleted completely, so it is not available anywhere on the sites. Thank goodness for the Wayback Machine at archive.org! When the World Wide Web began back in the 1990s, there was the promise of creating a huge library, larger than any physical library on Earth that everyone would have access to. Instead, much of the WWW library is quite ephemeral with materials existing for just a few years and then disappearing and other material inaccessible behind a paywall (an apt metaphor for today’s world). The 25+ years of Astronomy Notes is equivalent to eons in the virtual world and it’s still accessible for free; one career thing I’m proud of as I near retirement.
The evening sky belongs to Venus shining brightly in the west after sunset. Venus is now at the bottom mid-point of Leo. Its companion, bright Jupiter is now too close to the sun to see and it will be at conjunction with the sun on July 29. In the southwest, you’ll see the waxing crescent moon below the stars at the west end Virgo.
Above the moon, in between Leo and Virgo, a telescope will reveal the closest large galaxy cluster to us, the Virgo Cluster. It has many hundreds of galaxies (mostly spirals and irregulars) distributed in an irregular shape about 10 million light years across. It is about 49 to 59 million light years from us. Some elliptical galaxies are present in the central part of the cluster including a giant elliptical at the center (M87) that has become so large by gobbling up nearby galaxies that were attracted by its enormous gravity. M87 is the one with the several billion solar mass supermassive black hole at its center that was imaged by the Event Horizon Telescope a few years ago. Even though that black hole is big, the giant elliptical around it is thousands of times more massive with literally trillions of stars and five to six times the mass of the stars in the form of dark matter.
At several hundred trillion solar masses (at least), the total mass of the Virgo cluster is large enough that its gravity pulls nearby groups of galaxies toward it (including the Local Group in which our home galaxy, the Milky Way belongs). The Virgo cluster anchors the Virgo Supercluster (aka Local Supercluster) made of at least 100 galaxy groups and clusters. The Milky Way’s Local Group is near one edge of the Virgo Supercluster. The Virgo Supercluster is connected to a few other superclusters moving toward a large-scale structure called Laniakea that is one concentration of matter and dark matter making up the cosmic web in the observable universe.
Returning home: the moon will be next to Virgo’s brightest star, Spica on July 20. It will be at first quarter phase with nearly half of the near side that always faces Earth reflecting sunlight back to us. My astronomy magazine says the moon is “one day shy of first quarter” but since the precise first quarter with exactly 50% lit up occurs at 4:06 a.m. on July 21 and the moon will be well below the horizon, I think July 20 with its 47% illumination is closer to first quarter than July 21’s evening moon illumination of 57%. (I know that that point will be important to all of you, ahem!)
A waxing gibbous moon will be next to Scorpio’s heart, the supergiant Antares, on the night of July 24. Look to south when the evening twilight ends. The moon will be at couple of knuckles at arm’s length to the left of Antares. On the following night, July 25, an even fuller moon will be just a thumb width at arm’s length to the right of Sagittarius A* at the center of our galaxy. A supermassive black hole resides there but at just 4.5 million solar masses, our sun doesn’t respond to the black hole’s gravity, which is less than 1/20,000 that of the rest of the matter inside the sun’s orbit in the Galaxy.
The moon will be at full phase on July 29. Exact full phase happens at 7:36 a.m., the morning of July 29, so both July 28 and July 29 evenings will see a nice big nearly full moon rising shortly after sunset. The Southern Delta Aquariid meteor shower peaks at the end of the month but the gibbous moon is going to wash out a lot of it.
As temperatures rise, please check out https://www.kerncounty.com/government/aging-adult-services/services/cooling-centers for where are the cooling centers in Kern County. They open up when the temperatures are expected to get 105 degrees or hotter.
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Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com
