Skip to main content
U.S. flag

An official website of the United States government

Planetary Defense

Active
By Astrogeology Science Center October 7, 2022

At the USGS Astrogeology Science Center we conduct research on Planetary Defense. Planetary Defense involves predicting potential impactors (asteroids, comets), and studying how to deflect or divert them, as well as the potential effects of an impact. Effects include short-term effects such as blast damage, but also long-term effects such as climate and social impacts.

 

Cascading Hazards from an Impact

For intermediate sized impactors (300m - 1km diameter), regional cascading effects could be equally important. These regional effects could include reoccurring hazards such as debris flows and flooding. At the USGS Astrogeology Science Center, we are studying how these potential secondary effects relate to each other, and what may be done to mitigate such effects.

Image showing cascading hazards from an impactor.
Sources/Usage: Public Domain. View Media Details
The figure shows the cascading hazards that may result from an intermediate-sized impactor (asteroid or comet).

Near-Earth Asteroid - Surface Characterization

The USGS Astrogeology Science Center has provided software (Integrated Software for Imagers and Spectrometers) which has been used to support the NEAR Shoemaker, Hayabusa1, Hayabusa2, and OSIRIS-REx missions. These missions visited 433 Eros, 25143 Itokawa, 162173 Ryugu, and 101955 Bennu, respectively.  Itokawa, Ryugu, and Bennu are designated as Potentially Hazardous Asteroids (PHAs).

A review of common natural disasters as analogs for asteroid impact effects and cascading hazards

Modern civilization has no collective experience with possible wide-ranging effects from a medium-sized asteroid impactor. Currently, modeling efforts that predict initial effects from a meteor impact or airburst provide needed information for initial preparation and evacuation plans, but longer-term cascading hazards are not typically considered. However, more common natural disasters, such as vo
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin, Francis K. Rengers
By
Ecosystems Mission Area, Natural Hazards Mission Area, Volcano Hazards Program, Astrogeology Science Center, Geologic Hazards Science Center, Southwest Biological Science Center, Volcano Science Center

National preparedness strategy & action plan for potentially hazardous near-Earth objects and planetary defense

Near-Earth Objects (NEOs) are asteroids and comets that orbit the Sun, but have orbits that can bring them into Earth’s neighborhood—within 30 million miles of Earth’s orbit. Planetary defense is “applied planetary science” to address the NEO impact risks on Earth. This National Preparedness Strategy and Action Plan for Near-Earth Objects and Planetary Defense (2023 Planetary Defense Strategy) upd
Authors
Matthew Daniels, Lindley Johnson, Renata Kommel, Patrick Besha, Perry Brody, Kevin Conole, Kelly Fast, Angelo Fernandez, Ralph Gaume, Kevin Greenaugh, Ryan Guglietta, Diane Howard, Grace Hu, Christine Joseph, Brig Gen Traci Keuker-Murphy, L.A. Lewis, Lindsay Millard, Joel Mozer, Dianne Poster, Timothy N. Titus, Ashley Vanderley
By
Natural Hazards Mission Area, Astrogeology Science Center

Apophis specific action team report

This report about Asteroid (99942) Apophis's Earth close approach on April 13, 2029 was generated by a Specific Action Team (SAT) formed by the Small Body Assessment Group (SBAG) at the request of NASAs Planetary Science Division (PSD). The SAT assessed the current predictions for the effects that may occur due to the close encounter, evaluated observing capabilities, and identified possible inves
Authors
J. L. Dotson, M. Brozovic, S. Chesley, S. Jarmak, N. Moskovitz, A. Rivkin, P. Sanchez, D. Souami, Timothy N. Titus
By
Natural Hazards Mission Area, Astrogeology Science Center

Planetary defense preparedness: Identifying the potential for post-asteroid impact time delayed and geographically displaced hazards

A considerable amount of effort has been done to quantify impact effects from the impact of an asteroid. The effects usually considered are: blast, overpressure shock, thermal radiation, cratering, seismic shaking, ejecta, and tsunami (e.g. Hills & Goda, 1993; Collins et al., 2005, Rumpf et al., 2017). These first-order effects typically are localized in time and diminish with increased distance
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey
By
Natural Hazards Mission Area, Astrogeology Science Center

Asteroid impacts - downwind and downstream effects

For this abstract, we have selected an impact location, consistent with the PDC2021 initial scenario [1], in the San Juan Mountains, in southwestern Colorado. This is a low-density population area but is part of the watershed system within the Colorado River basin, a major source for water and power for the southwestern United States. Several large cities and major airports are potentially downwin
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin
By
Natural Hazards Mission Area, Astrogeology Science Center

Geology of five small Australian impact craters

Here we present detailed geological maps and cross-sections of Liverpool, Wolfe Creek, Boxhole, Veevers and Dalgaranga craters. Liverpool crater and Wolfe Creek Meteorite Crater are classic bowlshaped, Barringer-type craters, Liverpool was likely formed during the Neoproterozoic and was filled and covered with sediments soon thereafter. In the Cenozoic, this cover was exhumed exposing the crater's
Authors
E.M. Shoemaker, F.A. Macdonald, C.S. Shoemaker

Comet Shoemaker-Levy 9 at Jupiter

From the 16th to the 22nd of July, 1994, the world was privileged to witness an event that probably recurs less often than once a century. Collision of the brightest nuclei of Periodic Comet Shoemaker-Levy 9 produced enormous dark clouds that were the most dramatic and easily observed features on Jupiter recorded by human visual observation. They were seen by tens of thousands of people through hu
Authors
Eugene Merle Shoemaker

Gravity survey of the Mount Toondina impact structure, South Australia

Gravity and seismic reflection data, together with geologic mapping, indicate that the Mount Toondina feature in South Australia is best interpreted as an eroded 4-km-diameter impact structure consisting of a ring structural depression surrounding a pronounced central uplift. Beds at the center of the structure within the central uplift have been raised as much as 200 m from depth and deformed by
Authors
J. B. Plescia, Eugene Merle Shoemaker, Carolyn S. Shoemaker

Age and geomorphic history of Meteor Crater, Arizona, from cosmogenic 36Cl and 14C in rock varnish

Using cosmogenic 36Cl buildup and rock varnish radiocarbon, we have measured the exposure age of rock surfaces at Meteor Crater, Arizona. Our 36Cl measurements on four dolomite boulders ejected from the crater by the impact yield a mean age of 49.7 ± 0.85 ka, which is in excellent agreement with an average age of 49 ± 3 ka obtained from thermoluminescence studies on shock-metamorphosed dolomite an
Authors
F. M. Phillips, M.G. Zreda, S.S. Smith, D. Elmore, P.W. Kubik, R.I. Dorn, D. J. Roddy

Computer simulations of large asteroid impacts into oceanic and continental sites--Preliminary results on atmospheric, cratering and ejecta dynamics

Computer simulations have been completed that describe passage of a 10-km-diameter asteroid through the Earth's atmosphere and the subsequent cratering and ejecta dynamics caused by impact of the asteroid into both oceanic and continental sites. The asteroid was modeled as a spherical body moving vertically at 20 km/s with a kinetic energy of 2.6 × 1030 ergs (6.2 × 107 Mt ). Detailed material mode
Authors
D. J. Roddy, S.H. Schuster, M. Rosenblatt, L.B. Grant, Paul J. Hassig, K.N. Kreyenhagen

Why study impact cratering?

No abstract available.
Authors
Eugene Merle Shoemaker

At the USGS Astrogeology Science Center we conduct research on Planetary Defense. Planetary Defense involves predicting potential impactors (asteroids, comets), and studying how to deflect or divert them, as well as the potential effects of an impact. Effects include short-term effects such as blast damage, but also long-term effects such as climate and social impacts.

 

Cascading Hazards from an Impact

For intermediate sized impactors (300m - 1km diameter), regional cascading effects could be equally important. These regional effects could include reoccurring hazards such as debris flows and flooding. At the USGS Astrogeology Science Center, we are studying how these potential secondary effects relate to each other, and what may be done to mitigate such effects.

Image showing cascading hazards from an impactor.
Sources/Usage: Public Domain. View Media Details
The figure shows the cascading hazards that may result from an intermediate-sized impactor (asteroid or comet).

Near-Earth Asteroid - Surface Characterization

The USGS Astrogeology Science Center has provided software (Integrated Software for Imagers and Spectrometers) which has been used to support the NEAR Shoemaker, Hayabusa1, Hayabusa2, and OSIRIS-REx missions. These missions visited 433 Eros, 25143 Itokawa, 162173 Ryugu, and 101955 Bennu, respectively.  Itokawa, Ryugu, and Bennu are designated as Potentially Hazardous Asteroids (PHAs).

A review of common natural disasters as analogs for asteroid impact effects and cascading hazards

Modern civilization has no collective experience with possible wide-ranging effects from a medium-sized asteroid impactor. Currently, modeling efforts that predict initial effects from a meteor impact or airburst provide needed information for initial preparation and evacuation plans, but longer-term cascading hazards are not typically considered. However, more common natural disasters, such as vo
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin, Francis K. Rengers
By
Ecosystems Mission Area, Natural Hazards Mission Area, Volcano Hazards Program, Astrogeology Science Center, Geologic Hazards Science Center, Southwest Biological Science Center, Volcano Science Center

National preparedness strategy & action plan for potentially hazardous near-Earth objects and planetary defense

Near-Earth Objects (NEOs) are asteroids and comets that orbit the Sun, but have orbits that can bring them into Earth’s neighborhood—within 30 million miles of Earth’s orbit. Planetary defense is “applied planetary science” to address the NEO impact risks on Earth. This National Preparedness Strategy and Action Plan for Near-Earth Objects and Planetary Defense (2023 Planetary Defense Strategy) upd
Authors
Matthew Daniels, Lindley Johnson, Renata Kommel, Patrick Besha, Perry Brody, Kevin Conole, Kelly Fast, Angelo Fernandez, Ralph Gaume, Kevin Greenaugh, Ryan Guglietta, Diane Howard, Grace Hu, Christine Joseph, Brig Gen Traci Keuker-Murphy, L.A. Lewis, Lindsay Millard, Joel Mozer, Dianne Poster, Timothy N. Titus, Ashley Vanderley
By
Natural Hazards Mission Area, Astrogeology Science Center

Apophis specific action team report

This report about Asteroid (99942) Apophis's Earth close approach on April 13, 2029 was generated by a Specific Action Team (SAT) formed by the Small Body Assessment Group (SBAG) at the request of NASAs Planetary Science Division (PSD). The SAT assessed the current predictions for the effects that may occur due to the close encounter, evaluated observing capabilities, and identified possible inves
Authors
J. L. Dotson, M. Brozovic, S. Chesley, S. Jarmak, N. Moskovitz, A. Rivkin, P. Sanchez, D. Souami, Timothy N. Titus
By
Natural Hazards Mission Area, Astrogeology Science Center

Planetary defense preparedness: Identifying the potential for post-asteroid impact time delayed and geographically displaced hazards

A considerable amount of effort has been done to quantify impact effects from the impact of an asteroid. The effects usually considered are: blast, overpressure shock, thermal radiation, cratering, seismic shaking, ejecta, and tsunami (e.g. Hills & Goda, 1993; Collins et al., 2005, Rumpf et al., 2017). These first-order effects typically are localized in time and diminish with increased distance
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey
By
Natural Hazards Mission Area, Astrogeology Science Center

Asteroid impacts - downwind and downstream effects

For this abstract, we have selected an impact location, consistent with the PDC2021 initial scenario [1], in the San Juan Mountains, in southwestern Colorado. This is a low-density population area but is part of the watershed system within the Colorado River basin, a major source for water and power for the southwestern United States. Several large cities and major airports are potentially downwin
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin
By
Natural Hazards Mission Area, Astrogeology Science Center

Geology of five small Australian impact craters

Here we present detailed geological maps and cross-sections of Liverpool, Wolfe Creek, Boxhole, Veevers and Dalgaranga craters. Liverpool crater and Wolfe Creek Meteorite Crater are classic bowlshaped, Barringer-type craters, Liverpool was likely formed during the Neoproterozoic and was filled and covered with sediments soon thereafter. In the Cenozoic, this cover was exhumed exposing the crater's
Authors
E.M. Shoemaker, F.A. Macdonald, C.S. Shoemaker

Comet Shoemaker-Levy 9 at Jupiter

From the 16th to the 22nd of July, 1994, the world was privileged to witness an event that probably recurs less often than once a century. Collision of the brightest nuclei of Periodic Comet Shoemaker-Levy 9 produced enormous dark clouds that were the most dramatic and easily observed features on Jupiter recorded by human visual observation. They were seen by tens of thousands of people through hu
Authors
Eugene Merle Shoemaker

Gravity survey of the Mount Toondina impact structure, South Australia

Gravity and seismic reflection data, together with geologic mapping, indicate that the Mount Toondina feature in South Australia is best interpreted as an eroded 4-km-diameter impact structure consisting of a ring structural depression surrounding a pronounced central uplift. Beds at the center of the structure within the central uplift have been raised as much as 200 m from depth and deformed by
Authors
J. B. Plescia, Eugene Merle Shoemaker, Carolyn S. Shoemaker

Age and geomorphic history of Meteor Crater, Arizona, from cosmogenic 36Cl and 14C in rock varnish

Using cosmogenic 36Cl buildup and rock varnish radiocarbon, we have measured the exposure age of rock surfaces at Meteor Crater, Arizona. Our 36Cl measurements on four dolomite boulders ejected from the crater by the impact yield a mean age of 49.7 ± 0.85 ka, which is in excellent agreement with an average age of 49 ± 3 ka obtained from thermoluminescence studies on shock-metamorphosed dolomite an
Authors
F. M. Phillips, M.G. Zreda, S.S. Smith, D. Elmore, P.W. Kubik, R.I. Dorn, D. J. Roddy

Computer simulations of large asteroid impacts into oceanic and continental sites--Preliminary results on atmospheric, cratering and ejecta dynamics

Computer simulations have been completed that describe passage of a 10-km-diameter asteroid through the Earth's atmosphere and the subsequent cratering and ejecta dynamics caused by impact of the asteroid into both oceanic and continental sites. The asteroid was modeled as a spherical body moving vertically at 20 km/s with a kinetic energy of 2.6 × 1030 ergs (6.2 × 107 Mt ). Detailed material mode
Authors
D. J. Roddy, S.H. Schuster, M. Rosenblatt, L.B. Grant, Paul J. Hassig, K.N. Kreyenhagen

Why study impact cratering?

No abstract available.
Authors
Eugene Merle Shoemaker