Why don't people walk upside-down at the bottom of the Earth?


 

Asked … and answered: Think gravity.

Since 1997, Cornell graduate student volunteers in astronomy and physics have been joyfully responding to thousands of heavenly questions from quizzical kids and curious grown-ups at the website Ask an Astronomer.

People wonder why there are high tides at the full moon? (Michelle Vick, a graduate student in astronomy, explained gravitational tidal forces) Or why do planets rotate? (Angular momentum, said Jagadheep Pandian Ph.D. ’07, in his answer from 2002.)

Ask an Astronomer is the Cornell astronomy department's most visible public outreach activity. In May 2016, the website averaged 15,000 page views and 10,000 different users daily. As of this week, the popular website has had a gibbous 60,170,645 page views in its 19-year history.

The website got a cosmic facelift in 2015. Since then, the graduate student volunteers (about 15 of them) have been revising and updating the informative, down-to-Earth responses.

Sean Marshall, a doctoral candidate in astronomy, currently manages the website and he reads every question – and then sends it to volunteers for a reply. And that hard work isn’t lost on the faithful website readers, as one recently wrote: “Thank you for what your site offered to my family. It comes through on your website that you love to think, love to learn and love to teach. What a pleasure!”

Oh, and if a kid wants to know why the sky is blue? Sabrina Stierwalt Ph.D. ’09, now a staff scientist at the National Radio Astronomy Observatory, answered that in February 2006. It’s how the light scatters