Podcaster: Dr. Al Grauer


Title: Travelers in the Night  547 & 548: Impact Mars & Dragonfly

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • A given piece of ground on Mars receives several times more space rock impacts than a similar sized area on Earth.
  • A NASA team plans to fly a drone-like aircraft called Dragonfly around the surface of Titan.

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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547-Impact Mars

A given piece of ground on Mars receives several times more space rock impacts than a similar sized area on Earth.  Mars’s thin atmosphere means that craters and other surface markings these events produce persist over time.  From the first martian crater discovered by the Mariner spacecraft flyby in the 1960s until the present, our robotic emissaries have discovered more than 600,000 martian craters larger than a half mile in diameter.  

Further scientific research indicates  the number of impacts by 3 foot or smaller diameter objects, which cause fireballs on Earth, is likely to change by 3 to 15 times as Mars travels on its eccentric orbit about the Sun.  Recently, the NASA Mars Reconnaissance Orbiter photographed a new 50 foot diameter crater formed by a small, 5 foot diameter, space rock impacting Mars sometime September of 2016 and February 2019.  

The new crater’s image is striking. It is surrounded by a black and blue colored area more than 10 times the crater’s diameter with rays of debris extending over a several football stadium sized areas.  More data may reveal if the blue color around this fresh martian crater comes from newly exposed ice or some other exotic geology found on the red planet.  Perhaps, in the future the Martian tourist industry will bring visitors to view super meteor storms which occur each year when Mars is furthest from the Sun and to search for meteorites on the red planet’s surface.

548- Dragonfly

A problem searching for life outside of Earth is that we don’t know what extraterrestrial creatures may look like or where they might live.  In our solar system the most exotic body which contains the complex organic molecules necessary for life is Saturn’s Moon Titan. This strange world ,larger than the planet Mercury, has a thick nitrogen rich atmosphere with a surface pressure 50% greater than that of Earth.  Titan has clouds, rain, rivers, lakes, and oceans of organic liquid rich in carbon like methane and ethane.  You could walk around on Titan’s surface if you had a face mask to provide you with oxygen and a thermal underwear good to -290 degrees below zero Fahrenheit.  

Dr. Elizabeth Turtle, who received her PhD from the University of Arizona and is currently at Johns Hopkins University is leading a NASA team who plans to fly a drone like aircraft called Dragonfly around the surface of this exotic world.  Dragonfly will land in an area with dunes on Titan which are similar to those we find in Namibia in southern Africa. From there it will take flights up to 5 miles long on a route to sample areas with strange land forms until it arrives at the Selk impact crater where there is evidence of past liquid water and some of the complex chemicals which are necessary for life on Earth.  Dragonfly will be launched in 2026 and arrive in 2034.  

What it finds is likely to give us new insights into how life originated on Earth as well as to provide us reasons to value what we have at home.

For Travelers in the Night this is Dr. Al Grauer.

End of podcast:

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