Protesting museums reached a critical mass this week, for two different reasons. First, three dozen scientists sent a letter to two science and natural history museums, and started a petition, calling on them to cut ties with the Koch brothers and anyone else with connections to the fossil fuel industry. The petition calls for David Koch to be taken off the boards of the American Museum of Natural History in New York and the Smithsonian National Museum of Natural History in Washington D.C. The Koch brothers are billionaire donors to both musuems, and own Koch Industries with extensive fossil fuel holdings and have funded climate denial. There is currently a large protest movement to get companies, schools, and others, to divest fossil fuel funds, similar to the efforts in the 1980s to get companies to divest from investments in South Africa during the apartheid era. The scientists writing the letter say museums of science and natural history should not be associated with, “those who profit from fossil fuels or fund lobby groups that misrepresent climate science,” according to The Washington Post. The campaign is backed by the new mobile Natural History Museum. At the same time, in the art world, voices are rising against the Museum of Modern Art in New York, and its Curator-at-Large Klaus Biesenbach. Earlier this week, Christian Viveros Faune at artnet News wrote a through account of the issue calling for the firing of Biesenbach. He's being criticized for celebrity exhibitions that are not art, most recently one celebrating the pop singer Bjork. That show was called out by prominent art critics as a “fiasco" by Jerry Saltz, an “abomination" by Deborah Solomon, and the show that turned “MoMA into Planet Hollywood" by Michael Miller. Others complain about Kraftwerk's eight-gig show “Retrospective 12345678" in 2012, and the actress Tilda Swinton sleeping inside a glass box at MoMa, a rip-off of conceptual artist Chris Burden's 1972 "Bed Piece." And Biesenbach has organized only one solo show by a black artist at MoMA and MoMA PS1 since 1996. One anonymous source told artnet News, “Lots of trustees are unhappy with Biesenbach right now, but breaking ranks is a big deal. Change will come about only when the trustees who are in dissent get enough ammo to make their will explicit."