Bakersfield Night Sky — March 7, 2026
Ticekts for the March 19th showing of “Destination Mars” at the William M Thomas Planetarium are available through the Vallitix site.
Tonight the moon is now in a waning gibbous phase after the big full moon total lunar eclipse show earlier this week that won’t be visible again in our part of the world until 2029. The moon rises a little after 11 p.m. among the dim stars of Libra. A couple of nights later in the wee hours of March 10, an almost third quarter moon will be right next to the brilliant red heart of Scorpius, the red supergiant Antares. You’ll be able to see them traveling across the sky together starting at a little after 2 a.m.
Venus and Saturn are right next to each other this evening and tomorrow evening, about a thumb width at arm’s length apart from each other, in the western sky. Because they’ll be low in the sky just after sunset, you may need binoculars to pull out Saturn from the twilight glow (Venus will be easy to spot). Tonight Saturn will be to the upper left of Venus and tomorrow evening, it will be to the lower left of Venus. Tomorrow early morning, daylight saving begins!
Although I love to see the brilliant stars of Orion and his entourage of constellations around him, Canis Major, Canis Minor, Gemini, Auriga, and Taurus, I’m thankful when I can begin to see Leo rising in the east in the early evening because that means spring is just around the corner. For Bakersfield, that means that the weather has warmed up enough for the spring flowers in my yard to be in full bloom: African daisies, calendulas, and poppies galore!
How I locate Leo easily is to use the pointer stars in the Big Dipper of Ursa Major. Usually, we use the pointer stars at the end of the bowl part of the Big Dipper to point us to the North Star, Polaris, but if you go south of the bowl, the line from the pointer stars will lead you to the backward question mark of the head and front of the lion, an asterism called “the Sickle” that dates from agricultural times long ago.
Regulus is the brilliant, nearby (just 79 light years away), white-hot star at the bottom end of the Sickle (what would be the lion’s chest). It does have a blue tint to it because it is a B-type star which means it is much hotter and more massive than the sun. However, the temperature of Regulus is a bit complicated to specify because of its very rapid spin—less than 16 hours (compared to the sun’s spin of 25 days at its equator)! This makes Regulus really bulge at the equator—it’s 32 percent larger at the equator than at the poles (an “oblate spheroid”). Since the equator is significantly farther from the hot core, the equator has a temperature of 10,200 Kelvin while the poles are 15,400 Kelvin (the sun is 5840 K).
Regulus is near the end of its healthy adult stage of its life, fusing hydrogen to make helium in its core. It shines with a luminosity of about 360 times the sun and it has a mass about 3.4 times the sun. Because its mass is more than the sun, it will have a shorter life than the sun. The more massive stars are the gas-guzzling SUVs of the cosmos. Regulus is roughly 250 million years old, much shorter than the 4.6 billion year age of the sun and much less than the 10 billion year lifetime of the sun.
In my previous column, I described how the bright star Castor in Gemini was actually a multiple system. Well, Regulus is also a multiple-star system! Single star systems like the sun are the minority in the Galaxy. The easiest-to-see companion orbits the main star at about 100 times the distance that Pluto orbits the sun with a period of at least 125,000 years. That companion is actually a double-star system! Those stars orbit each other from a distance of a little over twice Pluto's distance from the sun. Both stars are smaller and dimmer than the sun, one an orange-warm star and the other a cooler red star.
The fourth star of the system orbits very close to Regulus in a time of just 40 days. It appears to be a white dwarf, the dead remains of a star that used to be slightly more massive than the main star. We know it once was more massive than Regulus because more massive stars live shorter lives than lower mass stars and the former star very, very likely formed at the same time as Regulus. When the former star went through its dying red giant phase, it dumped gas onto Regulus which is why Regulus is spinning so fast today and is also why the white dwarf has such an unusually low mass, just 30% of the sun.
As I noted above, the appearance of Leo rising in the eastern sky in the evening tells us that spring is coming soon. The official start of the season of spring is marked by the March equinox when the sun crosses the celestial equator heading northward and the amount of daylight will be longer than 12 hours in the following months. The sun crosses the celestial equator at 7:46 a.m. PDT on March 20. The evening of March 20 brings a beautiful sight of a very thin waxing crescent moon to the upper right of Venus, separated by slightly less than a fist width at arm’s length.
I hope to see you at one of the Planetarium shows. Always clear skies there!
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Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com
