Mrs. Baurbaurbiology.weebly.com/uploads/5/5/3/5/55354535/drake_equation_… · insights into what...
3
Mrs. Baurbaurbiology.weebly.com/uploads/5/5/3/5/55354535/drake_equation_… · insights into what we need to know." Steve Nadis is an Astronomy contributing editor. 26 Astronomy