? Science Café – “”Tree Rings: How do I love the Southwest? Let us count the ways!”” Paul R. Sheppard, associate professor of dendrochronology, will speak about tree rings. 5:30-7:30 p.m. Enoteca Pizzeria and Wine Bar, 58 W. Congress St.

? Steward Observatory public evening lecture. Yancy Shirley at the Steward Observatory will give a lecture on “”The Earliest Phases of Star Formation.”” 7:30-8:30 p.m. Steward Observatory, Room N210

? Monday night film series: “”Blackwater Invades Illinois.”” This documentary is about the Blackwater private military training facility outside of Chicago. 7-9 p.m. Aerospace and Mechanical Engineering building, Room S202

? Hands across campus. There will be performances and events on the UA Mall showcasing student diversity. 10 a.m. to 2 p.m.

? Weekly writing workshop. This week’s lecture will be on “”Style: Rules (and Non-Rules) of Usage.”” 5-6 p.m. Modern Languages building, Room 210