Mar 17th: Comet Catalina & Large Visitor

By on March 17, 2019 in

Podcaster: Dr. Al Grauer
Travelers in the Night Digest: Eps. 479 & 480: Comet Catalina & Large Visitor

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Hannes Groeller and Richard Kowalski spotted Comet C/2018 M1 (Catalina). Rounding the Sun at 25 miles per second it has just enough speed to escape our star’s gravity until the end of time.
  • Greg Leonard was surprised to discover 3,600 foot diameter asteroid 2018 ND1.

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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479 –  Comet Catalina
During the busy period of time that occurs as the Sun begins to light up the dawn sky, my Catalina Sky Survey teammates Hannes Groeller and Richard Kowalski spotted and reported their discovery of a fast moving unknown object in the constellation of Pisces.  Subsequently asteroid hunters reported that this new object has a bright gaseous coma surrounding it.  After a week of observations by astronomers in Arizona, Australia, the Canary Islands, Pennsylvania, Tibet,  France, and Italy, scientists at the Minor Planet Center calculated it’s path through space and gave it the name Comet C/2018 M1 (Catalina).  Even though this new comet’s orbit and that of the Earth come relatively close to each other, neither will be at that close point at the same time and Comet C/2018 M1 (Catalina) will remain faint, being only visible in electronic camera images.  A month after rounding the Sun at 25 miles per second Comet C/2018 M1 (Catalina) will continue on it’s parabolic path which means that it has just enough speed as it passes the Sun to escape our star’s gravity.  It’s voyage will be a long one, will cross the orbit of Saturn in 2020, and not reach Pluto’s average distance from the Sun until 2038.  Comet C/2018 M1 (Catalina) is eternal in the sense that it will likely  wander the vast space between the stars in our Milky Way Galaxy until the end of time. 

480 – Large Visitor
Statistically, asteroid hunters are thought to have discovered 90% of our potentially dangerous celestial neighbors greater than 1 KM in diameter.  Thus my Catalina Sky Survey teammate Greg Leonard was surprised to discover an unknown very large asteroid moving through the constellation of Persus.  After Greg posted his discovery observations, it was followed by observers in Arizona, Croatia, Italy, England, Illinois, Germany, and Kansas.  Their 71 hours of tracking data enabled scientists at the Minor Planet Center to calculate it’s orbit and name it 2018 ND1.  This 3,600 foot diameter asteroid had evaded detection because it’s orbit is inclined by 65 degrees to that of the solar system making it’s discovery likely only once every 23 years or so when it and the Earth are at a particular place In their respective orbits.  Fortunately on it’s current path 2018 ND1 never gets closer than 57 times the moon’s distance from us.  One it’s size strikes the Earth once every 250,000 years or so making a crater 6 miles in diameter and 2,000 feet deep. At 100 miles from ground zero such an impact would feel like a 7.4 magnitude Earthquake.  Glass windows would shatter and people in poorly designed buildings could be in danger.  Asteroid hunters hope to find any such global effecting impactors well in advance so as to allow for mitigating steps to be taken.

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

End of podcast:

365 Days of Astronomy
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