Is there water on Mars? There is plenty of evidence for flowing water in Mars’ distant past, but today, the Red Planet is mostly frozen and dry. Life as we know it needs water to survive, so understanding the elusive role of water on Mars will help us determine if the planet was ever habitable, and could pave the way for future human exploration. Although pure liquid water cannot exist on Mars today, naturally occurring salts across the surface may draw water down into the soil and dissolve to form persistent, hypersaline brines. How much water is available in these brines? Can they remain liquid despite Mars' cold, arid climate? Could they possibly even support life? In this talk, we’ll begin to unravel the mysteries of water on Mars through laboratory experiments at the University of Washington and new discoveries made by NASA’s Perseverance Rover.

One of the most remarkable differences between looking at most images of Solar eclipses and seeing an eclipse with your own eyes is seeing the distance that the corona extends outward from the Sun. Beyond its aesthetic appeal, seeing the corona is also scientifically valuable and provides a rare and short-lived opportunity to investigate features of the Sun that are otherwise invisible, not only for our eyes but also for scientific instruments. Our speaker this month, Professor Shadia Habbal, is a scientific eclipse chaser who leverages these opportunities to deepen our understanding of the solar wind and the Sun's magnetic field. Like all eclipse chasers, Professor Habbal's efforts can be thwarted by weather, and she and her team have pioneered approaches to mitigating these factors and squeeze every precious second of observation time from an eclipse. Monday's talk will be an opportunity to deepen your own understanding of the magnificent corona and increase your appreciation for it the next time you're fortunate enough to see a total Solar eclipse. Professor Habbal's description of her talk is below. I hope you'll be able to join us.

Total solar eclipses offer unique opportunities to explore the physical properties of the solar corona over an uninterrupted distance span of several solar radii starting from the solar surface. In this talk, I will give a brief overview of historical events associated with eclipses, including landmark discoveries that have ushered the astronomical community into space exploration. I will also cover examples of the trials and tribulations associated with eclipse expeditions, which have led to key discoveries from my team's imaging and spectroscopic observations.

The star clusters and nebulae that amateur astronomers observe usually lie within our own galaxy or its dwarf satellites. But it is also possible to use amateur equipment to observe some of these types of astronomical objects in the other spiral galaxies in the Local Group, the Andromeda Galaxy M31 and the Triangulum (or Pinwheel) Galaxy M33. Furthermore, other larger features that can't be easily observed in the Milky Way, such as star-forming regions, can also be seen in these galaxies using amateur equipment. Although these types of visual observations aren't easy to make, just finding these objects is a fun challenge that can be very gratifying. This month's speaker is one of our fellow club members, Howard Banich, who is very skilled in finding and drawing the detailed features of nearby galaxies. Howard is a very accomplished visual observer and prolific contributing editor for Sky and Telescope magazine. He is also an excellent speaker and it will be fun to hear about his observing adventures on Monday. His description of his talk is below. I hope you'll be able to join us.

M33 is a spiral galaxy just a bit further away than its much brighter and larger neighbor, M31. However, M33 has the advantage of being more face-on to our perspective, so we can see many of the individual objects within it. My talk will be about my visual explorations of M33 through telescopes 80mm to 30-inches in diameter, and will be a more in-depth examination than my Sky & Telescope article about M33 published in the November 2023 issue.

The Modern Eddington Experiment (MEE) started in 2017 with the eclipse that passed through the USA by utilizing modern telescopes and digital CCD cameras to acquire deflected stars. There were two successful parties Berry/Dittrich (and four students) in Oregon and Don Bruns in Wyoming. The success that Don Bruns obtained gave him the Chambliss Astronomy Award. The Berry/Dittrich execution was not as successful but did achieve determination of the Einstein Coefficient, which demonstrated that the experiment is possible with students. The MEE2024 project was organized by Dittrich, and there were a total of thirteen telescope camera stations at three locations across the path of the April 8 eclipse. The seven stations in Texas were clouded out, but the six stations in central Mexico had modest success, despite the clouds from a subtropical jet stream. They captured several hundred stars on thousands of plates with about 500 GB data in the 4.5 minutes of totality. The team of professors, amateur astronomers and 35 students from several colleges once again proved that this experiment is very hard to perform but with planning, training, calibrations and practicing procedures during totality better results than ever before can be achieved. Students in greater numbers once again successfully determined the Einstein Coefficient. This second success beckons the call for an even greater execution for the August 2, 2027 eclipse. This talk focuses on the past history of the experiment, the performance of MEE2024 and recruiting teams for MEE2027 in North Africa.

How will we, or at least our robot minions, get to the stars? You might answer "Well, using light sails, of course!" As it turns out, this is only one possible answer and maybe not the best. This question has received diligent, serious attention from a vibrant and growing community of researchers and many exciting possibilities that do not violate the laws of physics as we currently understand them and could be achievable with current or near-future technologies are being explored. Aside from possibly making nearby star systems accessible, these propulsion technologies would be extremely useful within the Solar System and could make incredible projects, like the Solar Gravitational Lens, practical. Our speaker is one of the main instigators of this movement and is orchestrating the construction of prototypes and experiments for testing these ideas. His description of his talk is below. It would be great to have you join us.

The initial reconnaissance of our solar system is complete, with every major object having been visited by our robotic emissaries. Each world visited surpassed the expectations of our imaginations. The ongoing exoplanet revolution kindles similar aspirations and begs the question: Will we ever send spacecraft to the stars? This talk will argue that the most profound and motivating of questions, "Are we alone?", can only be answered by direct exploration of other solar systems. Since characterization of biosignatures in exoplanet atmospheres made from earth will always remain ambiguous, it is likely that evidence for life around nearby stars will only be verified by in-situ observations. Fortunately, a stack of possible technologies exist to provide feasible, independent paths to the stars, enabling a robotic probe to return data within a human lifetime. Laser-driven lightsails, antiproton-catalyzed fission rockets, and particle-beam-driven spacecraft are credible means that could accelerate a robotic probe to 20% the speed of light. Significant challenges remain—this being the most difficult journey imaginable—but advances are being made as new concepts emerge. The existence of multiple paths ensures that, should showstoppers appear in a particular development roadmap, other approaches could be elevated to take their place. The talk will conclude with a look at some of the ongoing research into interstellar propulsion technologies at McGill University.

Monday's meeting will be an exhibition of some of the best aspects of our club. It will primarily be an in-person meeting and will be open to the general public. This year will also feature a visit from our friends at the Portland State Aerospace Society (PSAS), who will be launching their second satellite soon and will be showing off the earth-bound twin of their first satellite at the Fair. Oregon Astronomy & Rocketry will also be visiting and offering top-quality astronomy gear for purchase.

Although most of the meeting will be in-person, the club news and monthly sky/space report will be streamed via Zoom for members who can't or prefer not to attend the meeting in-person. It will also be possible to participate in one of the sessions of short talks via Zoom. Please note that some details might change by meeting time.

In addition, if you have something astronomy-related that you would like to share with other members, such as a cool scope or a specialized piece of equipment that you'd like to demonstrate, please feel free to bring it in. There will be space in the Auditorium for member displays.

White dwarf stars are the remnants left when lower-mass stars, such as our Sun, explode after depleting their fusable material. Although white dwarfs are less exotic than some of their more popular cousins, like neutron stars and black holes, recent studies have shown that they have amazing and unexpected properties. Along with their surprising properties, it can be a fun and challenging observing task to look for the white dwarfs in the hearts of planetary nebulae or in multiple star systems. This month's speaker, Dr Simon Blouin, is an expert in this type of star and is one of the authors of some of the recent studies. His description of his talk is below. It would be great to have you join us.

White dwarfs are the dense, Earth-sized remnants of stars, destined to cool down over billions of years after exhausting their nuclear fuel. This talk will delve into how these "dead stars" serve as valuable tools in astronomy. They act as cosmic clocks, allowing us to estimate the ages of stellar populations. Additionally, white dwarfs can reveal the chemical makeup of exoplanets they have consumed, and they provide a window into the behavior of matter under extreme pressure and density. New discoveries, including some very recent research I have been involved in, are challenging our understanding of white dwarfs. These findings suggest that some white dwarfs unexpectedly halt their cooling process for billions of years.

One ongoing mystery is how solar systems form. The initial challenge was to explain the formation of our own Solar System. But, at this point, a sizable number of extra-Solar planetary systems are known and have been well-characterized observationally. Most of these systems are very different from our own (partly due to observation bias) and a new challenge is to explain the formation of this wider range of solar systems and what conditions distinguish the various types. This month's speaker is Professor Tom Quinn from the University of Washington and he will be able to enlighten us on this fascinating topic. Professor Quinn leads the N-Body Shop, which creates and analyzes simulations of the formation of structures in the Universe. His description of his talk is below. It would be great to have you join us.

Although there are significant outstanding puzzles, our understanding of the formation of the planets in our Solar System is well developed. In particular, a scenario where much of the material formed into small solid bodies, which then grow by mutual collisions, offers a foundation for understanding the formation of the terrestrial planets, the outer planets, and the populations of comets and asteroids seen in the present day Solar System. However, planetary systems come in a variety of architectures, with a large fraction falling into a class known as Systems with Tightly-spaced Inner Planets. In these systems, all the observed planets are closer to their parent star than Mercury is to the Sun. Such configurations lend themselves to discovering details of the planets such as their mass, radii, and composition. The question therefore arises: can the same scenario that we use for the formation of the Solar System also account for these very different planetary system architectures?

This month we're hosting our second talk about upcoming missions in the Solar System. This month, Dr Carol Paty from the University of Oregon will be giving us her perspective. Dr Paty is a co-investigator on the ongoing Jupiter Icy Moons Explorer (JUICE) and upcoming Europa Clipper missions and a member of the science team for the Uranus Orbiter and Probe mission, which is currently in the planning stage. She'll again focus on the Clipper, since it is so close to launch, but might touch on some of the other missions, as well. Please see Dr Paty's description of her talk below. I hope you'll be able to join us.

Beginning with Galileo Galilei in 1610, the Jovian system of worlds has inspired us and provided a rich environment for paradigm change and discovery. Nearly 415 years from Galileo's discovery of the Jovian moons, we are poised to launch our next mission to further investigate the mysteries of Europa.

NASA's Europa Clipper spacecraft will launch in October 2024, with the goal of exploring Jupiter's moon Europa to understand its habitability. This robotic explorer will enter Jupiter orbit in April 2030, and, beginning March 2031, it will collect science data while flying past Europa 49 times. The mission will investigate Europa's habitability by studying its interior, composition, and geology, and will search for and characterize any current geologic activity including possible plumes. In this lecture, I'll discuss the mission's science objectives and how they will be addressed using an advanced suite of complementary remote sensing and in-situ instruments onboard Europa Clipper. From the short wavelengths of the ultraviolet to long wavelengths of radio, to a variety of compositional analysis techniques, to magnetic sounding of the interior, the diverse set of observations these instruments and investigations provide will paint a comprehensive picture of Europa's habitability and what lies beneath its frozen exterior. I'll also discuss the progress of the spacecraft assembly and testing as it makes its way to the launchpad.

This month starts a two-meeting series of talks about upcoming missions in the Solar System. This month, Dr Kate Craft from the John Hopkins Applied Physics Laboratory will be bringing us up-to-date on the Europa Clipper mission, which will soon disembark on its journey to explore the intriguing moon Europa in the Jovian system. Dr Craft is a member of the team responsible for maximizing the scientific potential of the data that the Clipper's instruments will measure. She is also a member of the team studying the possibility of a future lander for Europa. Please see Dr Craft's description of her talk below. It would be fun to have you join us.

Europa, an intriguing moon of Jupiter, has an icy exterior with a deep salty ocean beneath. Owing to its slightly eccentric orbit, this world undergoes tidal forcing that not only provides heat that maintains its liquid ocean but may also cause hydrothermal activity at its seafloor. This activity can provide nutrients and enable the reductant-oxidant mixing needed to support a habitable environment within Europa’s ocean. The Europa Clipper mission (europa.nasa.gov), scheduled to launch in October of this year(!!), will investigate Europa to constrain its habitability and seek to further understand its geology, interior, composition, and search for any current activity. If Europa harbors the needed conditions and ingredients for supporting life, potential follow-on missions could search for biosignatures there, and at other ocean worlds, potentially making the first discovery of life beyond Earth.