This area will cover relevant news of the threat to the planet from Near Earth Objects (NEOs) including concepts and designs for mitigation. All opinions are those of the author.

30 December 2005

Apophis, the Name

One of the most watched Near Earth Objects is Apophis, a 300+ m wide asteroid that will pass closely by the Earth in 2029 with a return in 2036. There is a small concern that depending upon its actual trajectory and its Earth flyby in 2029, an actual impact encounter could occur in 2036.

One item this author did not realize was the actual origin and meaning of the word Apophis, a god from ancient Egypt (From "Gods of Egypt" link below):

Name: Apep

Other Names: Apophis, the Destroyer.

Patron of: evil and darkness.

Appearance: a great serpent or crocodile.

Description: Apep was the ancient spirit of evil and destruction who dwelled in eternal darkness. Every day he would attempt to devour the Sun Boat of Ra as it sailed the heavens. Set's original role was to battle Apep and keep him from destroying the boat. Occasionally, Apep would succeed, and the world would be plunged into darkness (a solar eclipse?). But Set and his companion Mehen would cut a hole in Apep's belly to allow the Sun Boat to escape.

Apep commanded an army of demons that plagued mankind. Only by putting faith in the gods of light could people defeat the demons.

Every year, a ritual called the "Banishing of Apep" would be held by the priests of Ra. They would take an effigy of Apep and in the center of the temple they would pray that all the wickedness in Egypt would go into the effigy. Then they would trample the effigy, crush it, beat it with sticks, pour mud on it, and eventually burn and destroy it. In this way, the power of Apep would be curtailed for another year.

Worship: Not worshipped. Ever.

Link: Wikipedia entry on Apophis

Link: Gods of Egypt (Apep or Apophis, the Destroyer)

Link: Gods of Egypt - Apophis (Apep), the Enemy of Re

Guest Editorial: "Where’s Ben Affleck when you need him?"

From the Ridgecrest Daily Independent newspaper in California, comes a guest editorial about Apophis. A concise summary of the current situation regarding this Near Earth Object (NEO).

Guest Commentary: "Where’s Ben Affleck when you need him?"
Wednesday, December 21, 2005 11:18 AM PST
Kevin McClintock


Calculate Asteroid Impact Damage Online

"Welcome to the Earth Impact Effects Program: an easy-to-use, interactive web site for estimating the regional environmental consequences of an impact on Earth. This program will estimate the ejecta distribution, ground shaking, atmospheric blast wave, and thermal effects of an impact as well as the size of the crater produced."


29 December 2005

Gravity Tractor Journal Source

"Gravitational tractor for towing asteroids"
by Edward T. Lu and Stanley G. Love

Nature 438, 177-178 (10 November 2005)

"We present a design concept for a spacecraft that can controllably alter the trajectory of an Earth-threatening asteroid by using gravity as a towline. The spacecraft hovers near the asteroid, with its thrusters angled outwards so that the exhaust does not impinge on the surface. This proposed deflection method is insensitive to the structure, surface properties and rotation state of the asteroid."

Link: Nature Magazine Editor's Summary

Link: Nature Magazine Article Source

Podcast: Gravity Tractor Beam for Asteroids

"Forget about nuclear weapons, if you need to move a dangerous asteroid, you should use a tractor beam. Think that's just Star Trek science? Think again. A team of NASA astronauts have recently published a paper in the Journal Nature. They're proposing an interesting strategy that would use the gravity of an ion-powered spacecraft parked beside an asteroid to slowly shift it out of a hazardous orbit. Dr. Stanley G. Love is member of the team and speaks to me from his office in Houston."

Link: Story

Link: Podcast (mp3)

UK engineering feasibility study into missions for deflecting asteroids

The Engineering and Physical Sciences Research Council (EPSRC) in the UK is funding a three-year study (Starts: 1 June 2005, Ends: 31 October 2008, Value: £154,012) into interception and deflection strategies for asteroids found to be on a collision course with Earth. Investigators: Dr Gianmarco Radice, department of Aerospace Engineering, University of Glasgow, and Professor Colin McInnes, department of Mechanical Engineering, University of Strathclyde.

Link: Press Release

Link: Grant Summary

23 December 2005

NEO Astronomy Award and Smaller NEO Detection as part of NASA Authorization Act of 2005

Charles `Pete' Conrad Astronomy Awards Program and George E Brown Jr. NEO Survey Act were passed by United States legislature as part of NASA Authorization Act of 2005 (S.1281 Conference report).

"...The Administrator shall make one annual award [for $3,000 each] , unless there are no eligible discoveries or contributions, for each of the following categories:

(A) The amateur astronomer or group of amateur astronomers who in the preceding calendar year discovered the intrinsically brightest near-Earth asteroid among the near-Earth asteroids that were discovered during that year by amateur astronomers or groups of amateur astronomers.

(B) The amateur astronomer or group of amateur astronomers who made the greatest contribution to the Minor Planet Center's mission of cataloguing near-Earth asteroids during the preceding year."

"The Administrator shall plan, develop, and implement a Near-Earth Object Survey program to detect, track, catalogue, and characterize the physical characteristics of near-Earth objects equal to or greater than 100 meters in diameter in order to assess the threat of such near-Earth objects to the Earth. It shall be the goal of the Survey program to achieve 90 percent completion of its near-Earth object catalogue (based on statistically predicted populations of near-Earth objects) within 15 years after the date of enactment of this Act."

The following are from the National Aeronautics and Space Administration Authorization Act of 2005 (Engrossed Amendment as Agreed to by House and Senate)

Senate Bill: S1281 Subtitle C Section 321 (George E Brown Jr. NEO Survey Act)
Senate Bill: S1281 Subtitle B Section 613 (Charles `Pete' Conrad Astronomy Awards Program)

Link: S1281

Congressional Report: 109th Congress Report on Act (27 June 2005)

22 December 2005

Conference Update: ISDC 2006 Has Session on Planetary Defense (Currently Accepting Paper Abstracts)

The 25th International Space Development Conference (ISDC) will take place in Los Angeles from May 4-7, 2006. Sponsored by the National Space Society (NSS) and the Planetary Society, ISDC is a conference for specialists and non-specialists on a wide variety of topics, as NSS states: "ISDC 2006 will feature dozens of presentations, panel discussions, interactive exhibits and activities spanning the entire spectrum of space-related issues: exploration, tourism, science, technology, policy, and commerce."

ISDC 2006 will also have particular sessions on NEOs and planetary defense (Sessions 4.6 and 4.7 respectively).

Some of the speakers related to the topic of NEOs will include:
- Rusty Schweickart, Apollo 9 astronaut; Chairman, B612 Foundation
- Brig. Gen. Simon "Pete" Worden (USAF, Ret.)
- Dr. Brian Marsden, Director, Minor Planets Center, Harvard-Smithsonian Center for Astrophysics

Abstract deadline: Monday, February 1, 2006
Manuscript deadline: Friday, April 22, 2006

Link: Paper submission

Link: Main ISDC 2006 Conference

Article on New Pan-STARRS Telescopes Which Will Help in Asteroid Detection

"The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) project will deeply scan most of the night sky several times a month...Objects as dim as 24th magnitude—250 times fainter than objects detected by the current champ in asteroid spotting LINEAR—will pop out of the background and be analyzed for their threat potential...Pan-STARRS will bolster the Earth’s early warning system for threats from asteroids and comets."


20 December 2005

ESA Don Quijote Asteroid Mission

Don Quijote is an asteroid investigation, geophysical characterisation and deflection technological experiment mission.


18 December 2005

Wayback: The 2004 Planetary Defense Conference

For those who have not seen it, from a few years ago. The Planetary Defense Conference: Protecting Earth from Asteroids (February 23-26, 2004). Site includes video and output papers.


14 December 2005

Article on the Asteroid Tractor

"Astronauts push for strategies, spacecraft to prevent calamitous asteroid strike: Are we ready for doomsday?"

Source: Marcia Dunn, The Associated Press (via Pittsburgh Post-Gazette), 28 November 2005

"An 'asteroid tractor,' which would use the gentle gravitational attraction between spacecraft and asteroid to help change the asteroid's course. The tractor's thrusters are angled away to avoid breaking up the asteroid."


NASA Administrator Mentions Planetary Defense in Speech

NASA Administrator Michael Griffin:
"...And I'm also very intrigued by Ed Lu and Rusty Schweickart's ideas about nudging large near-Earth asteroids before they can pose a threat to humanity. We will most certainly continue our work to discover large asteroids close to the Earth."

Sorce: Science and Exploration; Speech by Michael Griffin to the American Geophysical Union," 07 December 2005.


Link: NASA

Conference: "Near Earth Objects: A Natural Hazard of Global Proportions"

Near Earth Objects: A Natural Hazard of Global Proportions, 23 November 2005, Royal Aeronautical Society, London

"This conference will consider the different types of near Earth objects, how we identify and track them, what would be needed to deflect a near-Earth object from an Earth colliding trajectory and how we communicate these issues at a public, scientific and political level."

Link: Press Release

Link: Conference

Selected Planetary Defense Books (Holiday Gifts)

Here are several relevant books related to the asteroid threat. These texts may not be for the general public but can be utilized for a more detailed analysis of the issue.

- "Hazards Due to Comets and Asteroids" (University of Arizona Space Science Series) by Tom Gehrels (Editor), Mildred Shapley Matthews (Editor), A. M. Schumann (Editor)

- "Comet and Asteroid Impact Hazards on a Populated Earth: Computer Modeling" by John S. Lewis

Gravitational Tractor Concept and B612 Foundation

Latest news from the B612 Foundation including new paper about the gravitational tractor for towing asteroids (concept paper by Ed Lu and Stan Love).


Article on Japan's Hayabusa Mission and Planetary Defense

"Asteroid Probe Yields Insight For Planetary Defense"
Leonard David,, 14 December 2005

"My personal opinion is that results from the Hayabusa mission can be used to engineer more robust strategies for future asteroid rendezvous missions," said Daniel Scheeres, Associate Professor of Aerospace Engineering at the University of Michigan in Ann Arbor."


30 November 2005

AIAA Space 2006 Conference and NEOs

The AIAA Space 2005 Conference (19 - 21 Sep 2006 in San Jose, California) will have a specific section dedicated to NEOs. The session will be in the session entitled “Logistics/ Recovery and Exploitation of Near-Earth Objects.”

Note: Paper abstracts are due by January 13, 2006.

"The close approach of the 1,059-foot-wide asteroid Apophis in 2029 and 2036 offers the potential that this or other near-Earth objects (NEO) could be captured and placed into a high Earth orbit, such as at an Earth–moon or Earth–sun Lagrangian site. Papers could address the means and methods for practically capturing such NEOs to eliminate future potential of their impacting the Earth, as well as to provide a significant source of extraterrestrial materials for future in-space logistics activities. Papers could identify practical means for recovering material from the NEOs, identify potentially attractive commercial applications of these materials, and identify the means to transport and process the materials. Papers could also identify specific orbital trajectories for capturing the NEOs and for conducting preliminary investigations and demonstrations, on a smaller scale, of the capture mechanisms. Finally, papers could identify beneficial space transportation and logistics infrastructure that would enable both the deflection of threatening NEOs or to enable their capture."


04 May 2005


Welcome to PlanetDefense. This area will cover relevant news of the threat to the planet from Near Earth Objects (NEOs) and specifically concepts and designs for mitigation.
Note: Any opinions expressed on the blog are solely those of the author. The site is not sponsored by, nor does it represent the opinions of, any organization, corporation, or other entity.