Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 635 & 636: Exploring Mars & 90 Inch

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • Our robotic emissary Perseverance landed in the 28 mile wide Jezero Crater on 18 February of 2021.
  • On Kitt Peak in Arizona, the Steward Observatory’s Bok telescope’s 90 inch light collecting mirror enables the discovery, study, and tracking of space rocks 3 or 4 times fainter then possible with any of our other telescopes

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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635: 90 Inch

On Kitt Peak in Arizona, the Steward Observatory’s Bok telescope’s 90 inch light collecting mirror enables the discovery, study, and tracking of space rocks 3 or 4 times fainter then possible with any of our other telescopes.  Even though the 90 inch was closed for the last 9 months of 2020 because of the Covid-19 Pandemic my Catalina Sky Survey teammate Hannes Groeller has made good use of the time which is available.  In addition to the time assigned to the Catalina Sky Survey,  Hannes has been able to obtain additional time for asteroid hunting by working with other projects which do not require the entire night and looking for asteroids for the remainder of the night.  His prime target areas are those which have not been covered by our team on Mt. Lemmon, Arizona for more than week and regions 60 degrees in front and behind our home planet where the gravity of the Sun and Earth create stable gravitational pockets at the L4 and L5 Lagrangian points.   

The L4 Lagrangian point which is on the Earth’s orbital path 60 degrees in front of us has one confirmed and one suspected Earth trojan asteroid.  These rare  space rocks have been temporarily captured by the combined gravity of the Sun and Earth and will dance with the Earth and Moon for several thousand years before embarking on another path about the Sun.  Over all our team has used the 90 inch Bok telescope to discover 36 Earth approaching asteroids. One of them is 2020 DB5,  a 5 football filed sized space rock, which on its current path can come to 6.5 times the Moon’s distance from us.  Another is 2019 YV4 a uhaul truck sized space rock which can come to less than the Moon’s distance from planet Earth.

636: Exploring Mars

We are lucky to be alive in an age when anyone with an internet connection can participate in the exploration of Mars.  Our robotic emissary Perseverance landed in the 28 mile wide Jezero [YEH-zuh-doh or DZEH-zuh-row] Martian Crater on 18 February of 2021.  In this place some 3.5 billion years ago a river carried sediments creating a delta in this crater near the edge of a lake the size of Lake Tahoe.  New technology allowed Perseverance to fly itself to a touch down in this ancient river delta between steep cliffs in a terrain featuring boulder fields, sand dunes, and more interesting land forms.  Scientists hope to find organic molecules and other signs of microbial life in this unexplored region of the Red Planet.  Perseverance has a suite of scientific equipment including 19 cameras, a small helicopter, a drill which will collect and save pieces of chalk sized core samples for later return to Earth, a ground penetrating RADAR, a Weather Station,  an X-ray spectrometer, and equipment to produce oxygen from Carbon Dioxide in the Martian atmosphere.  Here is where you come in.  Perseverance is sending back four to five hundred new raw images from the surface of Mars every day.  NASA Scientists are posting these new images directly on the NASA MARS 2020 Mission Perseverance Rover website.   Vote for the image of the week and download the previous images of the week.  

Your unique brain-eye combination may very well enable you to notice a previously unknown meteorite on the surface of Mars.  

Give it a try.

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

End of podcast:

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