Comments on: Student Questions: Collinsville High School http://www.astronomycast.com/astronomy/student-questions-collinsville-high-school/ Take a weekly facts-based journey through the cosmos with Astronomy Cast. Thu, 18 Mar 2010 06:54:42 +0000 http://wordpress.org/?v=2.9.1 hourly 1 By: Astronomy Cast http://www.astronomycast.com/astronomy/student-questions-collinsville-high-school/comment-page-1/#comment-642 Astronomy Cast Sun, 17 Aug 2008 01:14:58 +0000 http://www.astronomycast.com/?p=341#comment-642 Just to clarify on this, we're both right :-) Gravitational Time Dilation changes the wavelength of light in gravitational fields, and if a clock counts the passage of peaks, time will change. At the same time, velocity changes the passage of time via Time Dilation (yikes, too many similar terms!). Sometimes, the speed you're moving at dominates the time dilation and sometimes the gravitational well you've fallen into dominates. And I just might be evil and someday turn the questions of when which turn dominates into a homework problem... Just to clarify on this, we're both right :-) Gravitational Time Dilation changes the wavelength of light in gravitational fields, and if a clock counts the passage of peaks, time will change. At the same time, velocity changes the passage of time via Time Dilation (yikes, too many similar terms!).

Sometimes, the speed you're moving at dominates the time dilation and sometimes the gravitational well you've fallen into dominates.

And I just might be evil and someday turn the questions of when which turn dominates into a homework problem…

]]> By: jamnesia http://www.astronomycast.com/astronomy/student-questions-collinsville-high-school/comment-page-1/#comment-618 jamnesia Thu, 31 Jul 2008 00:38:11 +0000 http://www.astronomycast.com/?p=341#comment-618 I think Pamela’s response to why time slows when things enter a black hole wasn’t quite accurate. She described it as resulting from increasing velocity as things approach a black hole. However, it’s actually the black hole’s gravitational field that causes time to slow. This has been verified by placing very accurate clocks at the top and bottom of towers. So a space traveler could just hover at a fixed distance from a black hole and still need to adjust their clocks when they get home. However, technically gravity is acceleration, so in a roundabout way Pamela was correct. This is one of my favorite Podcasts and accessible to a wide audience. Keep up the good work! I think Pamela’s response to why time slows when things enter a black hole wasn’t quite accurate. She described it as resulting from increasing velocity as things approach a black hole. However, it’s actually the black hole’s gravitational field that causes time to slow. This has been verified by placing very accurate clocks at the top and bottom of towers. So a space traveler could just hover at a fixed distance from a black hole and still need to adjust their clocks when they get home. However, technically gravity is acceleration, so in a roundabout way Pamela was correct.

This is one of my favorite Podcasts and accessible to a wide audience. Keep up the good work!

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