how long ago was 33 ad in years

Some 400 million years ago, long before dinosaurs or even trees had evolved, an enigmatic organism towered over the landscape like a prehistoric monolith. Now, new research makes the case that the ... Smithsonian Magazine: Medieval Writings and Tree Rings Helped Researchers Track a Solar Storm From 800 Years Ago and Reconstruct Past Solar Cycles Medieval Writings and Tree Rings Helped Researchers Track a Solar Storm From 800 Years Ago and Reconstruct Past Solar Cycles Forbes: Did Humans Nearly Go Extinct 900,000 Years Ago? A Biologist Explains Space.com: A mass stellar migration billions of years ago may have helped life get started on Earth

MSN: The largest life-form on land 400 million years ago was one that scientists can’t explain The largest life-form on land 400 million years ago was one that scientists can’t explain