On the morning of July 13, 2025 William “Bill” Robert Sill passed away peacefully at Copper Ridge Rehab Facility in Butte, Montana following complications from a stroke in April 2025. Bill was 87 years old. He was born in Cleveland, Ohio on October 14, 1937 and was the 6th of 8 children born to Henry and Helen Sill.
As a child his family moved to Leonia, New Jersey where he loved hunting and fishing and spending time with his brothers in the outdoors. He later went to Michigan State University and received a BS in Geology. From M.I.T. he received his Master’s Degree and PhD in Geophysics. Notable places he worked included Bellcomm (Washington D.C.), University of Utah, and Montana Tech. He also wrote and published multiple papers that won awards from publications such as Scientific American. He also did geothermal research in Utah, and worked on the Apollo 17 moon mission. He was a wonderful mentor and teacher to his many students, friends, and family, and remained good friends with many of his graduate students from both Utah and Montana.
Bill lived a full life. He was an avid fly fisherman, skier, kayaker, rafter, hiker, camper, canoer, and mountain biker. He was a wonderful gardener, talented in cooking Chinese food, a dog lover, had a great respect and reverence for nature and the animal world, and was an epic story teller. His artistic side included woodcarving of Northwest Coast Native art, and he helped carve 5 of the Carousel horses that are located at Stodden Park in Butte.
He is survived by his wife Mary (Butte), daughters Helene and Kate and S/L Tory Sedgley (Salt Lake City), and dear friend Misti Andersen (Phoenix). Other surviving family members are Virginia Douglas (Edwin) (Tempe), and Henry Sill (Oregon). He was preceded in death by his parents, 5 brothers and 1 sister.
In lieu of flowers, please donate to a charity of your choice that supports wildlife, nature conservancy, or animal welfare.
Special thanks to the staff at Copper Ridge, the Honeybee Hospice nurses, and St. James Hospital, as well as all our family and friends near and far.
Celebration of Life to be held August 23, 2025 from 11am-3pm at the Elks Lodge, 206 W. Galena in Butte, Montana. He will be greatly missed.
Axelson Funeral & Cremation Services is privileged to care Bill and his family.
Please visit below to leave a condolence or share a memory of Bill.
Service Schedule
Celebration of Life
11am to 3:00 p.m.
Saturday August 23, 2025
Elks Lodge
206 W. Galena
Butte, MT 59701
Service Schedule
Celebration of Life
11am to 3:00 p.m.
Saturday August 23, 2025
Elks Lodge
206 W. Galena
Butte, MT 59701
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Alana LaRock says
Mary and Family. My prayers are with all of you for strength at this difficult time. Keep those memories close to your heart. Alana😪🙏🏻
Maureen Harrington Britton says
Dear Mary, Helene, and Kate, My sincere condolences to you for the loss of your husband and father. I so enjoyed looking at his beautiful, fine, art and carvings, and visiting with him and Mary. And those big, beautiful flowers! He was a being who added fascination and awe to life for all of us. I am so sorry for your loss. Sincerely, Maureen Britton
Julie Pascoe says
Mary, I have many memories of listening to your stories of Bill’s impact on his students, his family
and his meal preparation on Tuesday nights after you got home from the Loosely Knit group. Although I never had the privilege of meeting Bill in person, he lives in my memory as a treasured partner to you in your long and adventurous life with him. May he rest in peace and may you and the girls find your peace in the days and months ahead.
Wilma Immonen says
I only worked in the Geophysics Dept. for about a year. I was stuck by Bill’s dry sense of humor – dressing in a bathrobe, soap on a rope and a towel as the Hitchhiker in Hitchhiker’s Guide to the Galaxy. I saw it right away, none of the students had a clue. We had a laugh over that. Mary, you were always especially nice to me and I still have your gifts. My thoughts are with you.
Courtney Young says
To the Sill family, I want to thank you for sharing Bill with the MT Tech family. While i was getting my career started, there were senior faculty like Bill who helped, even if i was in Metallurgy. I am indebted and pay back by helping others now that i am senior. While we may have been in separate departments, we shared the same building and periodically got together. His sense of humor may have been dry, but his wisdom was second to none. I had lunch one time with him, Tom Finch (Mining), and Willis Weight (Geological). It ranks among my favorites; laughed so hard that I was tearing. God Bless you Bill. Rest in Peace.
Debbie Smith says
Mary – I’m so sorry, I only saw this today. Bill will be greatly missed and I’m glad I had a chance to get to know him. I still remember geophysics field camp in a June many moons ago where it was blizzarding and he made us soldier on. I’ll also miss chatting with him on the walking trail and cracking jokes with him.
Colleen Norbeck says
Mary
Please know you are in my thoughts and prayers.
I always enjoyed my visits with Bill.
May all your special memories bring you peace❣️
Hilary Risser says
Mary and family,
I was always awed by Bill’s talent with carving. The work he did for the carousel was absolutely amazing. I always admired how Bill balanced meaningful work with students at research at Tech with his pursuit of his personal passions. You are all in my family’s thoughts. We are all wishing you peace in this difficult time.
Terry Nichols says
As a former graduate student of Bill’s, I always though of him as a quiet, behind the scenes problem solver who touched the lives of many. He will always be remembered for the legacy he left behind. I will miss him. Thank you Bill for being such a great friend and mentor.
Joanne Cortese says
God bless Bill and all who loved him. Best wishes from a former MT colleague.
Lana & Joe Slouber says
Mary — Deepest sympathy from both of us. He was a talented and artistic person.
Christina Foley Boyer says
Mary and Family, please accept my deepest sympathy for your loss. It was my honor to work for Bill and the other members of the Physics/Geophysics Department for eight years. Bill was a real gem.