September 2018

Research focuses on impact cratering processes as revealed by laboratory impact experiments, the planetary surface record, and terrestrial ground truth.  Laboratory research includes atmospheric effects on ejecta emplacement, impactor survival, secondary impact processes, antipodal shock effects, high-speed spectroscopy of impact vapor/plasma, impact angle effects (shock propagation, vaporization, target damage, and flow-field evolution), projectile fate after impacts, and crater-scaling relations.  Of particular interest has been the origin of fluidized ejecta and blast winds around craters on Mars.  The pattern of crater degradation on Mars led to the hypothesis that Mars once had a very different location of its poles, and once had a family of satellites, now lost.  Such basic research led to participation in numerous NASA planetary missions including Magellan, Deep Impact, Stardust-NExT, EPOXI, and LCROSS.   Other basic research about the Moon includes: floor-fractured craters, beginning/end of volcanism, lunar swirl generation, polar volatile evolution, and origin of the nearside/farside dichotomy.  The last study argued that the distribution of smooth lava plains on the lunar nearside originated as the result of a giant impact on the far side. On Earth, his research has included the distribution of ejecta around Meteor Crater, discovery of 8 impacts in Argentina, and documentation of a witnessed crater-forming impact in Peru in 2007.  He has published more than 200 papers and authored a book called “Moon Morphology.” He received his BA from Carleton College (Northfield, MN) and PhD from the U. Texas-Austin.  He subsequently went to NASA Ames as an NRC post-doctoral researcher, then Staff Scientist at LPI (1976-1984), and finally Professor at Brown University.  He served as the Science Coordinator for the NASA Ames Vertical Gun Range from 1980 to 2014, and Director of the NASA Rhode Island Space Grant program (since 1992) and the Northeast Planetary Data Center at Brown University (since 1984).  He has been awarded the Distinguished Scientist Award (Hypervelocity Impact Society), Barringer Medal (Meteoritical Society), and G. K. Gilbert Award (Geological Society of America). Asteroid 16952 is named “PeteSchultz.”

Recently, I was able to take a short trip to Southern CA, one of the “bucket list” destinations of amateur astronomers everywhere. While I wasn’t able to take in everything available, I was able to hit some of the highlights. These included: A full night of observing with the famous 60-inch telescope on Mount Wilson, viewing some vintage 1800’s astronomical lithographs by artist Etienne Leopold Trouvelot, and a viewing of many original drawings done by Russell Porter at the Caltech Archives. My presentation today will provide details and many photos of the trip, most of which are specifically designed to induce envy among the audience members in attendance today.

I first came to Seagrave in 1972 as a result of one of the members of my high school astronomy club having a member who belonged to Skyscrapers. Belonging to Skyscrapers has brought me many long-lasting friendships, interesting travel opportunities, and lots of sharing of the night sky. I live outside of Worcester and the fact that I travel to North Scituate many times a year tells you just how great I think Skyscrapers is. I am currently privileged to be the president of Skyscrapers, and often think about how I can hardly believe that I’ve been involved for 46 years! 

Variable star observing is one of the most rewarding activities in which the amateur astronomer can participate. Indeed, estimates of the brightness of variable stars made by backyard astronomers are highly valued by the scientific community.  In this talk, I will explain how I got involved in variable star observing, and describe the types and nature of variable stars. I will conclude with a look at the American Association of Variable Star Observers (AAVSO), and demonstrate how to forward a variable star estimate to that organization.

This is a talk on meteorites and impactites, what they are and what they tell us about the world we live in. Peter has traveled the world to find rocks that are “out of this world.” He will have samples with him: meteorites from the Moon, meteorites that sent hundreds of people to the hospital, part of an asteroid that was found on an impact course with Earth, a piece of Mars, and many more meteorites. The presentation will touch on the formation of the solar system, the composition of the Earth, the role of asteroid impact on the Earth. If you have any rocks that you think might be a meteorite, be sure to bring them, as Peter will be happy to give his opinion on them.

Peter Scherff first started working with meteorites in the 1970’s when he used meteorites to create “out-of-this-world” jewelry. Working this amazing material piqued his interest, and he started studying meteorites to learn the science behind them. His studies have continued to this day. He prepares meteorites for study and/or display, makes thin sections for study, and etches iron meteorites to display their beautiful qualities. He has worked designing museum displays, selling and providing meteorites to both the public (universities, museums) as well as private collectors. He has also traveled the world, hunting for extraterrestrial rocks. Peter is a member of the Meteoritical Society, The International Meteorite Collectors Organization, as well as local and national astronomy associations.

It’s been 60 years since the launch of the first artificial satellite, Sputnik, and space is getting busier and busier. There are over 1,500 working satellites up there, but there are also over 17,000 known pieces of orbital debris whizzing around at up to 18,000 miles an hour. McDowell will  talk about the demographics of the satellite population: who is putting satellites up there, what are they doing, what the space junk is, and why there’s so much of it - and what can we do about it?

Come explore how easy it is to take dramatic photos with minimal equipment, as I provide a few tips on creating beautiful images of starscapes, constellations and more. No telescopes required!  

Many of us are familiar with home-built backyard telescopes, but how many can say that they have seen a home-built backyard planetarium? Francine Jackson, our resident planetarian, and Jim Hendrickson present a tale of an adventure they took in late 2017 to the faraway North Woods of Wisconsin to visit Frank Kovac and his planetarium. Built over the course of eleven years using over $100,000 of his own funding, Frank was inspired by a childhood visit to Chicago’s Adler Planetarium with his father, Frank, Sr., to build his own planetarium and share the wonders of the Universe in a unique way that no one else has ever done.

Recently I spent a week on the island of Mo’orea in the middle of the South Pacific. In addition to a productive physics workshop and amazing snorkeling on the coral reef I had the opportunity to see the southern sky in extremely transparent conditions of nearly zero light pollution. I will describe the experience through a series of photographs including images of the southern Milky Way.