Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 601 & 602: Phaeton’s Child & Solar Flares

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s 2 topics:

  • Phaethon and asteroid 2005 UD are closely related.
  • The NASA Solar Dynamics Observatory or SDO  has been keeping a 24/7 eye on the Sun for past 10 years.

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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601: Phaeton’s Child

Phaethon (Faith on)  is a strange, 4 mile diameter, blueish asteroid. It travels on an orbit which comes so close to the Sun that its exterior is heated to 1,500 F.  At that point any metals on its surface turn into a plastic goo.  Pantheon’s very elongated path takes it around the Sun across the orbits of Mercury, Venus, Earth, and Mars and back to the Sun again once every 1.4 years.  On this trajectory Phaethon travels with a trail of dust and debris which every December produces the spectacular Geminid Meteor Shower.  In 2009, the NASA spacecraft STEREO-A observed Phaethon to become twice as bright as it rounded the Sun suggesting that it had just belched a large quantity of dust. Still it is hard to understand how a 4 mile diameter object could continue to produce enough material to power a major meteor shower like the Geminids.  

In a separate development, a mile diameter asteroid, 2005 UD,  was discovered, years ago,  by my Catalina Sky Survey team captain Eric Christensen using our Schmidt telescope on Mt. Bigelow, Arizona.  Recently, the plot thickened when a team of scientists published a paper in the Journal Planetary Science which shows that Phaethon and asteroid 2005 UD are closely related.    What produced these two objects and how Phaethon, a relatively small space rock, produces enough debris to create a major meteor shower both remain a mystery.   When you go out to view the Geminids in December you might consider what they have to tell you about how this all happened.

602: Solar Flares

Some stars can have flares which can cause them to more than double in brightness in a few minutes. Fortunately our Sun does not do that and the Earth’s atmosphere and magnetic field protect us from the smaller flares which do occur on our star.  Even though a solar flare only increases the Sun’s brightness by a tiny percentage, a large solar can produce 10,000 times the amount of energy consumed by everyone in the USA each year. The tiny fraction of such a huge blast of energy the Earth intercepts,  can produce radio blackouts, disruption of electric power grids, enhanced auroras, and also could eliminate GPS and world wide communication satellites.  

The NASA Solar Dynamics Observatory or SDO  has been keeping a 24/7 eye on the Sun for past 10 years to alert us to solar flares and other important events which matter to humans.  In 10 years, SDO has recorded more than 200 solar flares which include about 30 flares which are followed, a few hours later, by another burst of energy which is  some times more intense than the original one. In 2020 the Sun is beginning a new solar cycle and by 2024 we should be seeing solar flares with increased frequency.  Since it takes days for the particles emitted by a solar flare to reach Earth the SDO’s early warning will be used to put our electronics into a safe mode.  Additionally, we need to figure out ways to protect astronauts on their way to the Moon or Mars from high energy protons emitted during a solar flare.

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

End of podcast:

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