May 2025 Meeting Notes

Bartlesville Astronomical Society Meeting Notes

May 5, 2025

Attendance: 

We had 14 members and 9 visitors in attendance this evening (including our guest speaker), in person and on Zoom.

Astronomical trivia—John G:

·       How fast are the Lyrid meteors when they enter Earth’s atmosphere? 105,000 mph.  Denise had guessed the closest, 50,000 mph.

·       What is the physically largest naked-eye-visible star?  Mu Cephei, the Garnet Star.  Its nucleus is over 1000 times bigger than our Sun.  Mu Cephei is a red supergiant star, magnitude -7.6.

·       What star has the fastest apparent motion?  Barnard’s star

Astronomy 101—What is a Drunken Moon?  Tricia P.:

·       A drunken moon happens when the Moon appears to sway or tilt.  Why does the moon appear this way?

·       Lunar libration: 

o   The Moon’s orbit is elliptical. 

o   The Moon’s rotational speed is constant, but its orbital speed changes. 

o   We see over 59% of the Moon’s face instead of just 50%.  We can see this 59% over a period of several weeks.

·       The Moon is low on the horizon

o   Refraction of light distorts the Moon’s shape. 

o   Our atmosphere bends light.

We need more volunteers for Astronomy 101, 10-minute astronomy, to cover the months of May through December. 

·   We need people to do Astronomy 101 for July and August.

·   Evan offered to present on Kitt’s Peak in July.

·   One of our guests, Tyler, offered to present on SETI—Search for ExtraTerrestrial Intelligence--in August.

Recent Club Events:

·       Billion Light Year Club at Boy Scout Camp McClintock, to see Quasar 3C 273, 2.5 billion light years away:  the weather precluded us from having this event on the intended date, April 18, as well as backup dates of April 25 and 26.

·       May 3, Astronomy Day at the library:  This was a very successful event!  Luann and John G organized this event and Craig, John B, Eugene, Daryl and Gary participated on the day.  We were set up both inside and outside the library. Indoors we had our recent library display posters as well as an ongoing YouTube presentation of Club photographs and an ongoing planetarium show.  We also had individual photographs for people to look at. Outside we had a telescope with a solar filter; images of the Sun could be viewed on a TV screen--including the largest sunspot of 2025 to date, which was over half the size of the Carrington sunspot in 1859!  We also had our handouts and some books on display. Our visitors all seemed very interested in and enthusiastic about the information and viewing experience we were able to provide to them!

Upcoming Club events:

·       May 20—Solar observing event at Bartlesville High School for AP Physics classes:  This event will be held during the school day for three morning classes and two afternoon classes, with 10-15 students per class. 

·       Sunfest, May 30-June 1:  Denise passed around signup sheets for booth setup the morning of May 30, booth staffing on May 30, May 31 and June 1, and takedown on the afternoon of June 1.

·       June 2:  BAS meeting, Moonwatch and the Early Days of BAS by Ron Carman, charter member of BAS in 1958

·       Daytime event at Woolaroc in August:  Denise has been contacted by Jan Tucker at Woolaroc to do a daytime event for all visitors to Woolaroc on a date in August, similar to what we did in August 2018.  We decided to do this on Saturday, August 23 and Denise will let Jan know.  Jan didn’t want to combine the daytime event with an evening star party for Woolaroc members only, as we did in 2018; she just wanted this to be a daytime-only event for all visitors to Woolaroc that day.

·       Event at Osage Hills State Park:  Denise has been contacted by Peggy Walker with Sidewalk Astronomy in Broken Arrow to have us participate in an event for Native American students from three schools that will be bussed into Osage Hills State Park on July 22.  Details are not fully worked out, but the intent is to have an event themed on Native American stories of the night sky/constellations, possibly with drummers.  We would bring telescopes—at least some of them optical—to the event, and would have each telescope focused on a particular object. 

Upcoming Astronomical Events:

May 12 – Full Moon/Flower Moon (micromoon)

May 20 – Last Quarter Moon

May 26 – New Moon

June 1 – Venus at greatest western elongation, at its highest in the morning sky before sunrise

June 2 – First Quarter Moon

June 11 – Full Moon/Strawberry Moon

June 18 – Last Quarter Moon

June 20 – June solstice

June 24 – Jupiter’s position in the sky will be close to the Sun, making it unobservable for several weeks

June 25 – New Moon

Treasurer’s Report – Evan Z:

·       Ending balance March 31, 2025: $18,260.81.

·       Deposits: 

o   $160.00 Benevity donations

o   $43.28 Truity savings account interest

·       Expenses:

o   $20.31, Pat reimbursement for two HDMI cords

o   $39.38, Tuxedo Storage - for which we're supposed to be reimbursed.

o   $67.22, Rice Creek mini-storage

·       Ending balance April 30, 2025: $18,337.18.

Website:

Pat has begun working on the website but needs more time!

Main presentation:  Our special guest speaker arranged through the Night Sky Network, Dr. Liliya Williams, Professor, Minnesota Institute for Astrophysics, presented on “What we know and don’t know about dark matter”. 

·       Dr. Williams began her presentation by outlining where our Solar System fits into the universe.  Our Solar System is but a part of a spiral arm in the Milky Way galaxy, which in turn is part of a local group of galaxies, which in turn is part of the Virgo cluster of galaxies. 

·       She then discussed what makes up the universe.  About 4% is ordinary matter, mostly elements in the periodic table of elements.  Dark energy comprises 70% and dark matter comprises 25%.  The dark matter is mostly in galaxies and in clusters of galaxies.

·       If you take total mass, and subtract the mass in stars, you are left with the mass of dark matter.

·       To measure the total mass of a galaxy, you use the motion of stars around a center, including the lensing effect of gravity as described by Einstein’s theory of relativity.  Stars and planets only account for a small fraction of the mass in galaxies.

·       Dr. Williams discussed familiar optics, such as the deflection of lights in headlights at night, with air used as a lens; candlelight viewed through a stemmed wine glass, with glass as a lens; and the wave action of water, with water as a lens.

·       She then discussed gravitational lensing.  The larger the deflection, the more mass the lens has.  The deflection of light by galaxies and clusters of galaxies is based on Einstein’s theory of relativity.

·       Dark matter exists.  It consists of elementary particles and is the dominant mass component of galaxies and the dominant mass component of the universe.

·       What we don’t know about dark matter:

o   What type of particles it consists of

o   How they relate to ordinary matter

o   How they fit into the standard mode of particle physics

o   Why dark matter is dark

o   Why dark matter is more abundant than ordinary matter

·       All ordinary matter radiates or shines.  Our Sun; rocks; volcanoes; cats; and water are all examples of ordinary matter that radiate or shine. 

·       Dark matter doesn’t radiate or shine.  That observation limits what forces it can interact through. 

·       The four forces of nature are gravity; electromagnetic force (why an object shines in X-rays or optical infrared light, etc.); weak nuclear force (radioactivity); and strong nuclear force, that holds atomic nuclei together.

·       Scientists look for dark matter interacting through weak forces, what are described as WIMPS—weakly interacting massive particles.  Such particles could have been produced in the early universe with the right abundance.  Physics gives us a range of candidate particles with the right properties.

·       Dark matter experiments need to take place underground.  Various centers have been set up to try to detect these particles, such as the Soudan Mine in Minnesota, the SNOLAB in Canada and CERN, the European Organization for Nuclear Research, in Switzerland, with its large hadron collider.

·       Why does dark matter matter?

o   Dark matter is 85% of all mass.

o   25% of all energy density is in dark matter.

o   The structure and distribution of galaxies and large-scale structures of the universe are determined by dark matter.

o   Dark matter is a new type of particle, a window into a new realm of particle physics.

o   We can look for collisions between dark matter and ordinary nuclei.

·       Dark matter is not the same thing as black holes.  Black holes come from ordinary material. Black holes may have formed in the very early history of the universe, perhaps during the first few seconds. 

Reminders:

BAS has equipment, books, educational materials and scopes available for loan to qualifying members.

Requests:  We would like to include member astrophotos, ranging from handheld smartphone pictures, to unguided camera on a tripod shots, to telescopic images, at future BAS meetings. Please email them to bvilleastro@gmail.com.

BAS needs volunteers:

We need volunteers for public star parties and other observing events.  All members are encouraged to help out with some of these events.  In addition to telescopes, help is needed with setup, answering general stargazing questions, conversing with and encouraging visitors, providing handouts and signup sheets. If you can help, contact jrgrismore@icloud.com.