Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 591 & 592: Teddy’s First Comet & Invasion

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  •   Teddy Pruyne discovered Comet P/2019 X1 (Pruyne) in Gemini.
  • Zdnenek Bardon in the Czech Republic was surprised, while taking images of Comet Atlas,  when his camera’s field of view was crossed by two perpendicular swarms of SpaceX Starlink satellites.

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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591: Teddy’s First Comet

One of the perks of being an asteroid hunter is to discover a comet and have it carry your name.  My Catalina Sky Survey teammate Teddy Pruyne was thus excited to spot a fuzzy object with a tail while asteroid hunting in the constellation of Gemini with our 60 inch telescope on Mt. Lemmon, Arizona.  Teddy’s excitement was tempered by the fact that he had come across many known comets in the same way.  This time when Teddy reported his observations to the Minor Planet Center his comet candidate turned out not to be previously have been known or named. For the next 8 nights his discovery was imaged and tracked by telescopes at 19 different observatories around the world.  Astronomers at the Minor Planet Center used these data to calculate the objects orbit’s about the Sun, give it the name Comet P/2019 X1 (Pruyne), and classify it as a Jupiter family comet.

Teddy’s first comet discovery is thus a member of a group of approximately 200 such small comets which circle the Sun with orbital periods of less than 20 years and whose paths are ruled by the largest planet in our solar system.  In its current orbit which takes Comet P/2020 X1 (Pruyne)  from slightly less than Jupiters distance from our Sun out to halfway to Saturn and back again every 15 years it is unlikely to stand out from the comet herd.   However since it crosses Jupiter’s path twice every 15 years it is likely to eventually impact Jupiter, be sent near Earth, or perhaps even be ejected from the solar system.

592: Invasion

Due to thoughtless outdoor night lighting on the surface and satellites in space the natural night sky is becoming a vanishing treasure.  Recently, astrophotographer Zdnenek Bardon in the Czech Republic was surprised, while taking images of Comet Atlas,  when his camera’s field of view was crossed by two perpendicular swarms of SpaceX Starlink satellites.  Visual observers from the light polluted skies of Chicago to one of the remnants of natural night skies at the Cosmic Campground International Dark Sky Sanctuary, in New Mexico can now also see Starlink satellites as they streak through the night sky.     

This collision between those who view the night sky as a treasure for all humanity and those who want to provide all of the pluses and minuses of internet services to anyone anywhere on the globe has begun with the launch of initial clusters of the proposed constellation of 30,000 telecommunication satellites.  In a hopeful sign,  SpaceX’s Elon Musk is taking steps in an effort to significantly decrease the brightness of new Starlink satellites by using shades to the block light reflected from their antennas from reaching observers the ground. SpaceX also plans to conduct maneuvers to keep the Starlink’s solar panels from reflecting light towards us during the orbit raise portion of their deployment.    From climate change to saving our natural night sky we must join together to prevent the thoughtless use of technology from damaging our environment.  

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

End of podcast:

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