Organization: Travelers in The Night
Description: Today’s 2 topics:
- The Breakthrough Starshot program has funded the creation of ‘Sprite’ , the world’s smallest spacecraft. About the size of a saltine cracker and having a mass of less than 2 dimes, the single-board spacecraft has all the essentials.
- When astronomers first discovered Apophis in 2004 it appeared possible that this 3 million ton, 1,200 foot diameter asteroid traveling at 8 mi/s could impact our planet creating a crater a several miles diameter and more than a half mile deep.
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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389 – Tiny Spacecraft
To reach the vicinity of the nearest star, 24 trillion miles away, in less than 20 years, an interstellar space probe would have to travel at a substantial fraction of the speed of light. Newton’s laws of motion, published 300 years ago, predict that the greater the mass of an object the greater is the force required to increase it’s velocity. In order to alleviate the need for the virtually unaffordable amount of energy required to accelerate a normal sized spacecraft to a speed of 20% of the speed of light, the Breakthrough Starshot program has funded the creation of ‘Sprite’ , the world’s smallest spacecraft. About the size of a saltine cracker and having a mass of less than 2 dimes, the single-board Sprite spacecraft has all the essentials; solar panels, computing electronics, thermometers, gyroscopes, radio communication equipment and more. Working prototypes have been launched into Earth orbit by the Indian Space Research Organization attached to the Italian Max Valier and Latvian Ventra satellites. One of them has sent back signals which have been received by Cornell University’s ground station.
Dr. Zac Manchester who started the Sprite Spacecraft program while earning a PhD at Cornell University envisions using tiny spacecraft to explore near Earth Space as well as asteroids and moons in our solar system. In the future, fleets of the decedents of Sprite could be sent to explore intriguing planets in nearby alien solar systems. These tiny explorers will be propelled by high power Earth bound lasers directed at their solar sails and could reach and explore distant planets in a reasonable amount of time.
390 – One in 100,000
Friday the 13th appears to continue to be a lucky day for the human race. When astronomers first discovered Apophis in 2004 it appeared possible that this 3 million ton, 1,200 foot diameter asteroid traveling at 8 mi/s could impact our planet creating a crater a several miles diameter and more than a half mile deep. Additional observations over the years have eliminated this possibility as Apophis streaks by closer than the communications satellites on that lucky Friday the 13th. Further, current calculations have reduced the chances of Apophis colliding with Earth in the next 100 years to about one in 100,000. However, over the millennia Apophis is likely to strike the Earth as does one it’s size once every 100,000 years or so.
Asteroid hunters have discovered more than 1,800 potentially hazardous asteroids whose size and orbits warrant special attention. Fortunately, none of them are currently on a collision course with our planet. These large space rocks will continue to be monitored as they pass near to other objects in space. Continuous tracking of dangerous objects is required since over time the uncertainty of their paths grows leading to a long term uncertainty about their collision possibilities with other objects.
The NASA Planetary Defense Program funds my team, the Catalina Sky Survey, to use three telescopes in the Catalina Mountains north of Tucson, Arizona to scan the skies to monitor the paths of potentially dangerous objects as well to discover any new dangerous celestial neighbors which may exist.
For Travelers in the Night this is Dr. Al Grauer.
End of podcast:
365 Days of Astronomy
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