Podcaster: Dr. Al Grauer
Title: Travelers in the Night Digest: Eps. 267 & 268: Hiding From ET & Mars Weather Report
Organization: Travelers in The Night
Link : Travelers in the Night
Description: Today’s 2 topics:
- Some scientists are concerned that we should not contact extraterrestrials if we find them. It might be possible to mask a transit of Earth from an extraterrestrial planet that would see one. The same system could be used as a signal beacon to say “Hi!” instead.
- The Curiosity rover has amassed a 2 year Martian weather dataset. The temperatures swing wildly from day to night and summer to winter.
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Bio: Dr. Al Grauer is currently an observing member of the Catalina Sky Survey Team at the University of Arizona. This group has discovered nearly half of the Earth approaching objects known to exist. He received a PhD in Physics in 1971 and has been an observational Astronomer for 43 years. He retired as a University Professor after 39 years of interacting with students. He has conducted research projects using telescopes in Arizona, Chile, Australia, Hawaii, Louisiana, and Georgia with funding from NSF and NASA.
He is noted as Co-discoverer of comet P/2010 TO20 Linear-Grauer, Discoverer of comet C/2009 U5 Grauer and has asteroid 18871 Grauer named for him.
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Transcript:
267 – Hiding From ET
It is unlikely that ET will discover humans by receiving the TV signals from “I Love Lucy” which are now 65 light years from Earth and are spreading into space at the speed of light, since recent scientific calculations indicate that we are probably alone in a 1000 light year cube centered on the Sun. However, the same analysis suggests that there may be several hundred advanced civilizations elsewhere in the Milky Way. Should mankind look forward to making contact with one of them? Some scientists like Stephen Hawking and others who have thought about human-alien contact and say maybe not. They are concerned that human-alien contact might turn out for mankind to be like what the residents of the Americas received from the invading Europeans. This unhappy prospect has prompted a discussion about the wisdom of humanity hiding from ET and/or ET hiding from us.
So far the NASA Kepler spacecraft has discovered more than 4,500 planets orbiting distant stars by measuring the tiny dip in the host stars brightness as one of it’s planet’s pass in front of it. Undoubtedly ET is aware of this process and may be hiding from us by shining a powerful laser in the right direction to mask the tiny dip in their Sun’s brightness as their planet passes in front of their host star. A tunable, programmable laser could create an effective mask which would frustrate attempts to discover a planet. We could hide Earth from discovery in this way by using the power generated from 100 wind turbines. On the other hand humans could announce their presence to the Milky Way by using such a system for signaling instead of hiding.
268 – Mars Weather Report
Before you pack your bags for a trip to Mars you will want to check out the weather data that NASA’s Curiosity Mars Rover has recorded over the past two Martian years.
Prepare yourself for wide swings in temperature. On a warm summer day, Curiosity recorded a high temperature of 60.5 degrees Fahrenheit, however, at night even during the warmest part of the Martian year the temperature can fall to 130 degrees below zero F. During the Martian winter it is really cold. The extreme low temperature recorded by Curiosity in the Gale crater is minus 148 degrees Fahrenheit.
Mars is extremely dry. Its atmosphere contains a thousand to ten thousand times less water than what we experience on planet Earth. Even so the Martian relative humidity has been measured to be as high as 70% during the winter. So far Curiosity has not spotted any frost accumulating on the ground.
An extreme aspect of the Martian year is the capture and release of carbon dioxide at the poles causing it’s atmospheric pressure to vary by 25% or so.
Keep your eye on the Martian Weather Channel. Global dust storms often hide surface features for days or weeks. Martian storms can be exciting but in reality pack little destructive force. For example, in the thin Martian atmosphere a wind of 150 miles per hour would not straighten out an American flag. However, be ready for dust devils 19 miles which are high crackling with lightning.
There is no getting around the fact that you will need a space suit and long woolies to survive on Mars.
For Travelers in the Night this is Dr. Al Grauer.
End of podcast:
365 Days of Astronomy
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