Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps 647 & 648: Vigilance & Smoky Nights

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • Greg Leonard had a night which was mostly to partly cloudy, had periods of rain sprinkles after midnight, and finally a clear patch in the early morning. Then he discovered 2021 LL1 in the constellation Hercules.
  • Climate change has enabled wildfires to move to higher elevations that until recently were too wet to burn.

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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647: Vigilance

From dusk to dawn on a clear night an asteroid hunter with the Catalina Sky Survey is busy keeping up with images taken by the telescope at 30 s intervals. A cloudy night is different. Before opening the dome shutter and the telescope mirror covers it is necessary to determine if the telescope mirror will be safe from high humidity, rain, sleet, and or snow. After opening a constant vigilance is necessary since mountain top weather can go from bad to worse in a matter of minutes. Recently on such a difficult night my Catalina Sky Survey teammate Greg Leonard had a night which was mostly to partly cloudy, had periods of rain sprinkles after midnight, and finally a clear patch in the early morning. He was rewarded for opening and closing the dome a number of times when the sky cleared long enough for him to begin searching the sky for Earth approaching objects with our 60 inch telescope on Mt. Lemmon, AZ. Greg was delighted when he picked up an unknown fast moving object, the size of a large Uhaul truck 1.4 million miles away, in the constellation of Hercules.

After Greg reported his observations to the Minor Planet Center his new object was tracked by telescopes in Arizona, England, France, and Illinois. Astronomers used these data to calculate the new object’s orbit about the sun and give it the name 2021 LL1. This year 2021 LL1 passed about 3 lunar distances from us. Not to worry. If 2021 LL1 did impact Earth it would explode high in the stratosphere and produce a few fresh space rocks for meteorite hunters to discover.

648: Smoky Nights

Until recently smoky nights at the observatory were rare. Now they have become more common place as wild fires continue to devastate portions of the western United States.  On a very smoky night my team the Catalina Sky Survey is unable to discover or track asteroids which come close to our home planet.  In a recent article published in the Proceedings of the National Academy of Sciences a team of researchers report that climate change has enabled wildfires to move to higher elevations that until recently were too wet to burn.  

In the past these areas possessed snow packs well into the summer and experienced early snow storms in the fall making their moist forests relatively fire proof.  Data shows that rising temperatures during past 34 years has caused 31,470 square miles of high elevation forests in the western USA to become fire prone.  This vast area the size of the state of South Carolina has not been subject to fire supression, logging, and other human activities which implies that their increased risk of catastrophic fires is do entirely to climate change.  An example of this is the Cameron Peak Fire which in 2020 became Colorado’s largest fire in history as it burned its way up to 12,000 feet at the upper tree line of the Rocky Mountains. The consequences of expanded fire prone areas  goes far beyond missing a few nights data at the telescope.  Potentially millions of people will be at increased risk of respiratory aliments.  Further the burn scars left behind will adversely affect the quality and quantity of the precious water these high altitude areas provide to a a dry and thirsty west.

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

End of podcast:

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