Planetary Defense

Extracted Attributes

• Field

  Applied planetary science

• Purpose

  Monitor and protect Earth from asteroids, comets, and other objects in space

• Key Threats

  Asteroids, Comets, Near-Earth Objects (NEOs)

• Primary Goal

  Prevent destructive impact events from Near-Earth Objects (NEOs)

• Expert Warning (2016)

  Earth is unprepared for such an event (NASA scientist)

• Expert Statement (2018)

  It's 100 percent certain we'll be hit by a devastating asteroid, but we're not 100 percent sure when (B612 Foundation)

• Historical Impact Examples

  Chicxulub crater, Shoemaker-Levy 9 impacts on Jupiter, 2013 Chelyabinsk meteor, Tunguska event

• Proposed Deflection Methods

  Modify trajectory (deflection), Modify object by breaking it up (fragmentation)

• Key Challenge (Fragmentation)

  Asteroids may reassemble due to gravity after disruption

• Potential Consequences of Impact

  Massive tsunamis, widespread firestorms, impact winters

• Preparation Time Needed (Estimated)

  5 to 10 years for virtual impactor avoidance

• Greatest Threat to Planet (Stephen Hawking)

  Asteroid collision

Timeline

• Asteroid impact believed to have caused Chicxulub crater and the extinction of non-avian dinosaurs. (Source: Summary, Wikipedia)

  66000000 BCE

• The Tunguska event, a large explosion likely caused by an asteroid or comet airburst, occurred. (Source: Related Documents, Wikipedia)

  1908-06-30

• Shoemaker-Levy 9 impacts Jupiter, drawing renewed attention to impact threats. (Source: Summary, Wikipedia)

  1994

• The Chelyabinsk meteor event occurred, further highlighting the threat of NEOs. (Source: Summary, Wikipedia)

  2013

• NASA officially established the Planetary Defense Coordination Office (PDCO). (Source: Web Search - PDCO Wikipedia)

  2016-01

• A NASA scientist warned that Earth is unprepared for a major asteroid event. (Source: Wikipedia)

  2016

• The B612 Foundation reported that a devastating asteroid impact is 100 percent certain, though the timing is unknown. (Source: Wikipedia)

  2018-04

• Physicist Stephen Hawking, in his final book, identified asteroid collision as the biggest threat to the planet. (Source: Summary, Wikipedia)

  2018

• Scientists reported that asteroids may be much more difficult to destroy than previously thought, potentially reassembling due to gravity. (Source: Summary, Wikipedia)

  2019-03

• NASA astronomers reported that 5 to 10 years of preparation may be needed to avoid a virtual impactor, based on a simulated exercise. (Source: Wikipedia)

  2021-05

• NASA's DART mission successfully impacted Dimorphos, demonstrating asteroid deflection by reducing its orbital period. (Source: Summary, Wikipedia)

  2022

• China plans to launch a deflection mission to the near-Earth object 2015 XF261. (Source: Summary, Wikipedia)

  2027

• Estimated impact of China's planned mission on 2015 XF261. (Source: Wikipedia)

  2029-04

Asteroid impact avoidance

Asteroid impact avoidance encompasses the methods by which near-Earth objects (NEO) on a potential collision course with Earth could be diverted, preventing destructive impact events. An impact by a sufficiently large asteroid or other NEOs would cause, depending on its impact location, massive tsunamis or multiple firestorms, and an impact winter caused by the sunlight-blocking effect of large quantities of pulverized rock dust and other debris placed into the stratosphere. A collision 66 million years ago between the Earth and an object approximately 10 kilometers (6 miles) wide is thought to have produced the Chicxulub crater and triggered the Cretaceous–Paleogene extinction event that is understood by the scientific community to have caused the extinction of all non-avian dinosaurs. While the chances of a major collision are low in the near term, it is a near-certainty that one will happen eventually unless defensive measures are taken. Astronomical events—such as the Shoemaker-Levy 9 impacts on Jupiter and the 2013 Chelyabinsk meteor, along with the growing number of near-Earth objects discovered and catalogued on the Sentry Risk Table—have drawn renewed attention to such threats. The popularity of the 2021 movie Don't Look Up helped to raise awareness of the possibility of avoiding NEOs. Awareness of the threat has grown rapidly during the past few decades, but much more needs to be accomplished before the human population can feel adequately protected from a potentially catastrophic asteroid impact. In 2016, a NASA scientist warned that the Earth is unprepared for such an event. In April 2018, the B612 Foundation reported "It's 100 percent certain we'll be hit by a devastating asteroid, but we're not 100 percent sure when." Also in 2018, physicist Stephen Hawking, in his final book, Brief Answers to the Big Questions, considered an asteroid collision to be the biggest threat to the planet. Several ways of avoiding an asteroid impact have been described. There are two primary ways: to modify the trajectory of the object so that it does not collide with the Earth, or to modify the object by breaking it up so that the resulting fragments do not collide with the Earth or their smaller size reduces the subsequent hazard posed to the Earth. Nonetheless, in March 2019, scientists reported that asteroids may be much more difficult to destroy than thought earlier. An asteroid may reassemble itself due to gravity after being disrupted. In May 2021, NASA astronomers reported that 5 to 10 years of preparation may be needed to avoid a virtual impactor based on a simulated exercise conducted by the 2021 Planetary Defense Conference. In 2022, NASA spacecraft DART impacted Dimorphos, reducing the minor-planet moon's orbital period by 32 minutes. This mission constitutes the first successful attempt at asteroid deflection. In 2027, China plans to launch a deflection mission to the near-Earth object 2015 XF261, with the impact estimated to occur in April 2029.

Web Search Results

• Planetary defense: Protecting Earth from space-based threats

  Planetary defense is the effort to monitor and protect Earth from asteroids, comets and other objects in space. Earth's gravity attracts more than a hundred tons (more than 90 metric tons) of small objects and dust from space daily, according to NASA. Most of this material burns up in the atmosphere without any effect on the planet; larger chunks may produce a bright streak of light that's visible in the night sky or a small meteorite for a rock hunter to find. [...] # Planetary defense: Protecting Earth from space-based threats Every day, Earth is bombarded with hundreds of tons of small objects. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Planetary defense is designed to monitor and protect Earth from asteroids like this on in the image. This graphic illustration of a large asteroid crashing into Earth and throwing up a large plume of debris. [...] But life on Earth has been drastically altered by asteroid impacts before; the Chicxulub crater, for example, is evidence of the planet-shaking strike that led to the extinction of the non-avian dinosaurs. Planetary defense systems work to identify potentially harmful objects (PHOs, in NASA's Planetary Defense Coordination Office terminology) in proximity to Earth. While these systems have not yet identified or dealt with any major threats, NASA, the European Space Agency (ESA) and other

• Planetary Defense - DART mission

  kilometers) of Earth's orbit. Planetary defense is "applied planetary science" to address the NEO impact hazard. [...] Planetary defense encompasses all the capabilities needed to detect and warn of potential asteroid or comet impacts with Earth, and then either prevent them or mitigate their possible effects. Near-Earth objects (NEOs) are asteroids and comets that orbit the Sun like the planets, but with orbits that bring them into or through a zone between approximately 91 million and 121 million miles (195 million kilometers) from the Sun, meaning that they can pass within about 30 million miles (50 million [...] Planetary defense efforts of NASA's Planetary Defense Coordination Office (PDCO), of which the DART mission is one component and the first mission being flown by the PDCO. (Credit: NASA)

• Planetary Defense Coordination Office - Wikipedia

  Wikipedia # Planetary Defense Coordination Office The Planetary Defense Coordination Office (PDCO) is a planetary defense organization established in January 2016 within NASA's Planetary Science Division of the Science Mission Directorate. It includes a Near Earth Observations Program which funds telescopic searches and orbit calculations. Planetary Defense Coordination Office [...] In January 2016, NASA officially announced the establishment of the Planetary Defense Coordination Office (PDCO), appointing Lindley Johnson to lead it as Planetary Defense Officer. The PDCO was given the job of cataloging and tracking potentially hazardous near-Earth objects (NEO), such as asteroids and comets, larger than 30–50 meters in diameter (compare to the 20-meter Chelyabinsk meteor that exploded over Russia in 2013) and coordinating an effective threat response and mitigation effort. [...] | | | | --- | --- | | | | | Agency overview | | | Formed | January 2016 (2016-01) | | Jurisdiction | United States | | Headquarters | Washington, D.C. | | Motto | Hic Servare Diem (Latin) "Here to Save the Day" | | Agency executive | Lindley Johnson, Planetary Defense Officer | | Parent department | Science Mission Directorate, Planetary Science Division | | Parent agency | NASA | | Website | nasa.gov/planetarydefense |

• PI - Planetary Defense - NASA

  The traditional approach to planetary defense consists of momentum transfer between the impactor and the threat that changes the threat orbit such that it misses the Earth, which is generally known as “deflection.” The PI approach is different in that we do not use momentum transfer, but rather energy transfer. We do not mitigate the threat by requiring it to miss the Earth, but rather we explore mitigating the threat by pulverizing it and then using the Earth’s atmosphere as a shield. This [...] terminal solution to planetary defense using existing technologies. The approach works in extended time scale interdiction modes where there is a large warning time, as well as in short interdiction time scenarios with intercepts of minutes to days before impact. In the terminal interdiction mode, the bolide fragments of roughly <10m diameter allow the Earth’s atmosphere to act as a “bullet-proof vest,” where the fragments either airburst in the atmosphere, with the primary channel of energy

• Planetary Defense News - NASA Science

  How would humanity respond if we discovered an asteroid headed for Earth? NASA’s Planetary Defenders is a gripping documentary that follows the dedicated scientists involved in the high-stakes world of asteroid detection and planetary defense. [...] NASA is bringing the world of planetary defense to the public with its new documentary, “Planetary Defenders.” What would humanity do if an asteroid were headed for Earth? The documentary takes viewers inside the real-life efforts of scientists and engineers…

• Instance Of

  Q7889