The Road to W Supernovae Mostly Near and

The Road to W: Supernovae Mostly Near and Some Far, 1978 -1994 Thanks to Saul Perlmutter, Nobel Prize, 2011 Respectful Backgrounder for his talk “We got the Prize”

1970’s: Luie’s Wisdom, which Rich and others endeavored to diffuse into group: • Go after a big goal • “If your junk pile is not big enough, you are not trying hard enough” • “If you ever knew how hard an experiment would be before you went into it, you would never do anything” • “Good Experimental Physicists have a controlled disrespect for authority” • Build a team of the smartest and hardest workers you could find

Background, circa late 1970’s: “Missing Mass of the Universe - “Dark Matter” • It neither emits nor absorbs nor scatters light but long suspected to be a major component of our Universe • Suspected since the 1930’s – galaxies in clusters moved faster than expected, given the visible mass in clusters of galaxies — Rationale: mass makes things move, and their was too little visible mass to account for the speed of things. • In the 1970’s, Vera Rubin found very good evidence in how fast stars are rotating around the center of their galaxies! • Other measurements of large scale structure indicate dark matter

~ 1976 -78 --Milestones in Berkeley Supernova Searches : • Search for “Missing Mass” of the Universe is realized by Rich to be a “big goal” worthy of Luie’s • Rich learns of work of Robert Wagoner ~ 1977 -- (Stanford) – Supernove to measure geometry of the Universe • Rich decides to do Supernova Search, Physics: -- if you know intrinsic brightness measure distances combine with velocities one gets geometry/mass of Universe

The Big Tool/method: Supernovae!!: Explosive end of a star’s life, which can be seen across the Universe! Supernova can be as bright as a whole galaxy! But hard to find!! This was the first supernova we saw, in M 99 galaxy in 1986.

History: Stirling Colgate in 1960’s: Father of “Digital Astronomy” • Stirling Colgate had made a valiant attempt to discover supernovae, but technology was not up to it. • Nike-Ajax Missile Mount for 30” telescope mount, microwave link from telescope to Mainframe on New Mexico Institute of Mining Campus etc.

Automated Telescopes: 1978 – Luie to Rich Muller: Why not do Stirling Colgate’s Supernova Experiment with these telescopes? Luie suggests use of Depart. of Defense Telescopes used to watch ICBM’s re-enter atmosphere in South Pacific Test Range on Kwajalen Atoll (~2500 miles southwest of Hawaii)

History and Milestones in Supernova Searches: • Rich hires Carl (1980) to help undertake, design, build, and lead day-to-day project – funding from Rich’s prizes, etc. • We recruit great graduate students, LBL engineers (Robie Smits, John Yamada), and team goes into heavy duty software, hardware, algorithm development, and data acquisition • Finding telescopes that really worked was quite hard – went into negotiations over 5 telescopes

The Challenge: • Observe 100’s of galaxies a night, and find a few pixels, out of a 100 million or so, that are brighter than they were before. -- Automated Telescope -- Very sensitive digital camera -- Software for telescope control, observatory control, camera control, image processing and discovery. • Software and computers were essential, and we were always at the limit of the computing hardware • 1986 find our first supernova, and then find another 25 or so over the next few years. Luie scanned a few times! First successful automated supernova search, and we found some valuable examples of sub-classes of Type I supernovae. .

Leuschner Observatory (over the Hill from Berkeley): 1984 --after tries at other observatories hardware started to work!)

History and Milestones in Supernova Searches The First Cosmological Supernova by Danish-led Collaboration: • A Danish-Australian-British team finds the first cosmological supernovae, then gives up. “Too hard” 1988: Danes, Australians, and British find Z = 0. 28 supernova, use 1. 5 meter telescope, reasonably tiny CCD. Then they give up!

1989: Warrick Couch(of Danish collaboration) Comes to Santa Cruz for a conference, and we talk: He says let us use Anglo-Australian Telescope(AAT) for a Deep Search! we start first very serious cosmological supernova search 1) Needed big CCD for wide field of view (Thompson 1000 x 1000 pixels– I bought) 2) Needed Big telescope ( Warrick -AAT 4 -meter diameter mirror) 3) Needed custom optics to de-magnify image onto tiny CCD. 4) Needed to get data back (always an issue)

Anglo Australian Search Heidi Newberg, Warrick, Carl, Shane Burns, Warrick, , Gerson Goldhaber, and Saul (not pictured)

The CCD: Thomson (French -- 1 K x 1 K) At time, the biggest CCD on a large telescope!

Demagnifying Optics Mirror:

Demagnifying Optics Refracting Elements:

Putting It All Together on AAT 4 meter Telescope:

Bad weather and other issues at AAT--> Isaac Newton Telescope in Canary Islands : Find our First Cosmological Supernovae in 1992!!

Saul Takes Over on Isaac Newton Search and also he secures use of several more telescopes! (1992 -2012) – I start education project Hands-On Universe • Saul did Brilliant job – e. g. , I did not think we would get telescope time because of interesting peer group): • Saul does an amazing (“cosmic”) job inventing, leading, managing, making good decisions, working hard, etc. • Leads to first announcment of Omega Lambda and evidence for Dark Energy ~ 1996. (Saul’s talk)

An Unlikely Spin-off from Luie: Carl and Education – “Hands-On Universe” Educational System: • Get kids excited about science and engineering by undertaking as real as possible science and engineering --Use real data and real astronomy for classroom education – remote telescopes, image processing on computers, real data • High School Teacher helped find first Isaac Newton Supernovae!! • Students have found hundreds of asteroids now, and captured first light from one supernova. • We have reached about 8, 000 teachers (Rich Lohman here) around the world – Kenya too (Ms. Susan Murabona, African HOU leader is an attendee of this symposium! Stand up Rich and Susan!!)