Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 607 & 608: Good Night & Triple Comet

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Teddy Pruyne was granted a good night during which he posted observations of 7 unknown moving points of light. One of them has been named 2020 PB1.
  • Worachate Boonplod discovered three comets SOHO-4049, SOHO-4050, and SOHO-4052. 

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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607: Good Night

Nearly every day during the monsoon rainy season in the American southwest,  afternoon thunderstorms require putting mountain top telescopes and cameras into a lightning safe mode.  After the threat of electrical activity has past, it takes hours to cool the camera to a – 104 C required to produce electronic noise free images.  Often when the equipment is ready, either it is still cloudy or the humidity is too high to begin to search the sky for Earth approaching space rocks.  After many humid cloudy nights waiting for clear skies, my Catalina Sky Survey teammate Teddy Pruyne  was granted a good night during which he posted observations of 7 unknown moving points of light.  One of them has been named 2020 PB1.  It is a city block sized asteroid, which Teddy spotted as it streaked through the constellation of Andromeda some 47 million miles from Earth.  

Although in 2020 this Potentially Hazardous Asteroid  will not get closer than 28 million miles to planet Earth, it bears watching,  since at some point in the distant future on its current orbit it can approach to about 3 times the Moon’s distance from us.  According to the Purdue University and Imperial College of London’s Impact calculator an asteroid the size of 2020 PB1 strikes the Earth every 28,000 years or so producing a crater 1.4 miles wide and 1500 feet deep in sedimentary rock. Although the chances it will impact Earth are vanishingly small, rest assured that asteroid hunters will continue to track 2020 PB1 to make sure it doesn’t become a threat as it comes near Earth and crosses the orbit of Mars.

608: Triple Comet

Recently amateur astronomer, Worachate Boonplod discovered the 4049th comet recorded in the imaging data produced by SOHO, the  ESA/NASA Solar and Heliospheric Observatory. This discovery was accomplished through NASA’s citizen science Sungrazer project which enables anyone in the world to discover a comet in the SOHO data.   

Worachate first spotted his comet discovery as a small dim smuge at the edge of a SOHO large angle spectrometric coronagraph image.   As this comet approached the Sun it became elongated.  When this sun grazing comet entered a higher resolution SOHO camera field, amazingly, it turned out to be three comets SOHO-4049, SOHO-4050, and SOHO-4052. This is probably the first and only trip near the Sun by this tiny family of comets which are likely to disintegrate under our Sun’s fierce radiation.  Over half of the more than 4000 previously unknown comets found in the SOHO data have been made by amateurs who carefully scan the  solar images produced by this unique observatory.  

Further 85% of the SOHO comet discoveries belong to the Kreutz family whose path about the Sun has an 800 year orbital period.  This comet stream is named in honor of Heinrich Kreutz who in the late 1800’s discovered the first its members.    It is likely that the Kreutz family of comets are parts of a single comet which was ripped apart by the Sun’s gravity. To discover your very own comet visit the NASA Sungrazer Project website for the data and tips on how to proceed.  Your comet is out there.

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

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