Bakersfield Night Sky — September 20, 2025
Tickets are still available for the September 25 show “From Earth to the Universe” and for the October 2 show “Mars One Thousand One”. On September 26, tickets will be available for “Black Holes” showing on October 23. Tickets will open up for “Earthquake” on October 3. The first Friday and Saturday of October will be the “Mesmerica” shows. Links to the tickets sites are posted on the William M Thomas Planetarium’s Shows page .
Last weekend the clouds and Garnet wildfire smoke cooperated to stay clear of the skies above Sequoia National Park for the annual Dark Sky Festival. Hard to believe that that was the twelfth one! Many hundreds of people viewed the star clusters, planetary nebulae, supernovae remnants, Saturn, and the Andromeda Galaxy through the telescopes set up by the Kern Astronomical Society. Skies were nice and dark, free of the light pollution of the city. So wonderful to see the Milky Way stretching across the sky overhead and thousands of stars!
Saturn has been getting brighter and brighter as it heads for opposition, being directly opposite the sun on our sky. This occurs tonight! However, its rings will be nearly edge-on, so this opposition will be a bit more muted than other oppositions. It’ll reach magnitude 0.58, making it the third brightest “star” in the early evening sky. Look for it in the southeast below the Great Square of Pegasus at that time
On September 7, the sun, Earth, and moon were lined up to make a lunar eclipse with the full moon going through Earth’s shadow. Unfortunately for us, the eclipse happened while the moon was still below our horizon. Those in Africa, Asia, and Australia were able to see it. Whenever there’s a lunar eclipse, then a solar eclipse will happen either two weeks earlier or two weeks later. Tomorrow, September 21, the new moon will cover up part of the sun to make a solar eclipse but again, in North America, we won’t be able to see it. Sigh! Those in New Zealand, southern Pacific Ocean, and the penguins in Antarctica will be able to see the partial solar eclipse—with appropriate solar filters.
The following day, September 22, marks the official start of autumn for us in the northern hemisphere (it’ll be the start of spring for those south of the equator). Since the beginnings of each three-month season is tied to the position of the sun with respect to the celestial equator (projection of Earth’s equator onto the sky), we know the precise minute when a season begins, even if the weather conditions are saying something different. Autumn will officially begin as the sun crosses the celestial equator at 11:19 a.m. Pacific Daylight Time on September 22. With the sun rising due east and setting due west at the times many are commuting to or from work on our east-west running roads, we’re going to have the sun blinding us in our rear-view mirrors or in our windshields for the next couple of weeks or so!
There are always several great astronomy research news items every week and I don’t have space to cover them all. I have to pick and choose and you’ve probably figured out that I have certain biases as to which ones I’ll talk about in these night sky columns. One bias I have is Mars and we had a doozy of a research result last week with astrobiology news coming from the Perseverance rover on Mars.
In a peer-reviewed paper published last week, an international team led by Joel Hurowitz of Stony Brook University announced the results of their study of the “Cheyava Falls” rock from the northern edge of a now-dry river valley running into the ancient lake that filled Jezero Crater. Round black spots and round rings looking like leopard spots formed via chemical reactions that seem to be most easily explained as coming biological processes and less likely from abiotic processes instead. Although there are ways to explain the features through non-biological means involving sustained high temperatures, acidic conditions, and binding by organic compounds, the detailed analysis by Hurowitz’s team shows that high temperatures or acidic conditions were not present and we don’t know how the chemical binding by organic compounds would have happened under low temperatures. Because a biological explanation is the more likely one while non-biological processes may still be possible, this is classified as a “potential biosignature”. More data and further study needs to be done by returning the rock sample back to Earth for analysis with instruments that are much too large to launch in a rocket to Mars. Perseverance has done about all it can to analyze the rock with the various sophisticated instruments it has.
With the results now published in a peer-reviewed paper, NASA is encouraging the rest of the scientific community to poke holes in the argument that biological processes are the best or easiest explanation for the data and to propose other possible tests that Perseverance could do. In the “Confidence of Life Detection” scheme of seven benchmarks or levels of confidence that a set of observations stands as evidence of life, this result is between levels 3 and 4. At level 3 is the demonstration/prediction of biological production of signal in the environment of detection. Level 4 is all known non-biological sources of signal are shown to be implausible in that environment. Bring the samples back to Earth, so we can to get to the higher levels of confidence!
Hope to see you at one of the Planetarium shows!
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Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com
