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Archive for the ‘asteroid/comet impacts’ category: Page 19

Mar 15, 2021

NASA’s Planetary Defense: “Potentially Hazardous Asteroid” Predicted to Safely Pass by Earth on March 21

Posted by in categories: asteroid/comet impacts, existential risks

The interplanetary interloper won’t come closer than 1.25 million miles to Earth, but it will present a valuable scientific opportunity for astronomers.

The largest asteroid predicted to pass by our planet in 2021 will be at its closest on March 21, providing astronomers a rare opportunity to get a good look at a rocky relic that formed at the dawn of our solar system.

Called 2001 FO32, the near-Earth asteroid will make its closest approach at a distance of about 1.25 million miles (2 million kilometers) – or 5 1/4 times the distance from Earth to the Moon. There is no threat of a collision with our planet now or for centuries to come.

Mar 12, 2021

Scientists Are Planning to Build Noah’s Ark on the Moon

Posted by in categories: asteroid/comet impacts, cryonics, existential risks, life extension

Earth is destined for disaster. This is a good insurance policy.


In 2013, a cataclysmic meteor the size of a six-story building broke apart above Chelyabinsk, Russia, and the resulting blast was stronger than a nuclear explosion. In 2068, astronomers believe a potentially hazardous “God of Chaos” asteroid could slam into Earth. Both events suggest humans—and every other animal and plant on Earth—are much more susceptible to total annihilation than we think.

Continue reading “Scientists Are Planning to Build Noah’s Ark on the Moon” »

Feb 28, 2021

Did A Comet Fragment Kill The Dinosaurs? Not Likely, Say Researchers

Posted by in categories: asteroid/comet impacts, existential risks

The latest hypothesis that the demise of the dinosaurs was precipitated by a cometary fragment that slammed into the Gulf of Mexico some 66 million years ago is being met with skepticism in the Earth sciences community.

Feb 20, 2021

An asteroid is approaching, so I invited one of Earth’s defenders to dinner

Posted by in categories: asteroid/comet impacts, existential risks, satellites

Near-Earth Asteroid 99942 Apophis will be visible on Sunday. Some say it could ultimately destroy satellites and spaceships. The creators of the Unistellar eVscope telescope are trying to marshal our defense.

Feb 15, 2021

How Jupiter Set Off A Chain Of Events That Killed The Dinosaurs

Posted by in categories: asteroid/comet impacts, existential risks

A fragment of a large, long-period comet was most likely responsible for the impactor that killed off the dinosaurs.

Jan 3, 2021

NASA, FEMA, International Partners Plan Asteroid Impact Exercise

Posted by in categories: asteroid/comet impacts, existential risks, health

Each day this week, we will be providing updates on a fictional impact scenario playing out at the International Planetary Science Conference in College Park, Maryland. This scenario is designed to help key decision makers practice for a real asteroid impact. Currently, there is no known asteroid with a significant probability of impacting Earth in the next century. Day 5: What Was This Exercise All About? This week at the 2019 Planetary Defense Conference, conference participants were tasked with responding to a hypothetical asteroid impact scenario in which they have eight years to stop an asteroid on a collision course with Earth. Every day, the audience heard updates — at one point, they weren’t sure whether the 140–260-meter-wide (500−850 feet) asteroid was actually going to hit Earth. Once they found out it was on a certain collision, NASA and space agencies around the world decided to send a fleet of kinetic impactors to deflect the asteroid. The kinetic impactors hit the asteroid…but ended up splitting off a chunk, which, on Day 4 (four years from impact), again was headed towards Earth.


While headlines routinely report on “close shaves” and “near-misses” when near-Earth objects (NEOs) such as asteroids or comets pass relatively close to Earth, the real work of preparing for the possibility of a NEO impact with Earth goes on mostly out of the public eye.

Jan 2, 2021

Scientists: Life on Earth Likely Started in Meteor Craters

Posted by in categories: asteroid/comet impacts, existential risks

A new study is flipping the script on the effects of massive meteor impacts. While an ancient impact is commonly to the extinction event that killed the dinosaurs, scientists are now starting to suspect that an earlier impact could have jumpstarted life on Earth in the first place.

Scientists have long suggested that meteorites carried the ingredients necessary for life to Earth, but new research suggests that meteor impacts also created the ideal conditions for life to emerge as well, The Weather Network reports. Because of that, the scientists suggest that space agencies ought to pay special attention to similar craters when hunting for life on the Moon, Mars, or beyond.

Dec 28, 2020

Double Asteroid Redirection Test (DART) Mission

Posted by in categories: asteroid/comet impacts, existential risks

DART is a planetary defense-driven test of technologies for preventing an impact of Earth by a hazardous asteroid. DART will be the first demonstration of the kinetic impactor technique to change the motion of an asteroid in space. The DART mission is in Phase C, led by APL and managed under NASA’s Solar System Exploration Program at Marshall Space Flight Center for NASA’s Planetary Defense Coordination Office and the Science Mission Directorate’s Planetary Science Division at NASA Headquarters in Washington, DC.


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Dec 19, 2020

Tunguska explosion in 1908 caused by asteroid grazing Earth

Posted by in categories: asteroid/comet impacts, existential risks

So we’ve had close calls before, huh?


In the early morning of June 30, 1908, a massive explosion flattened entire forests in a remote region of Eastern Siberia along the Tunguska River. Curiously, the explosion left no crater, creating a mystery that has puzzled scientists ever since — what could have caused such a huge blast without leaving any remnants of itself?

Now Daniil Khrennikov at the Siberian Federal University in Russia and colleagues have published a new model of the incident that may finally resolve the mystery. Khrennikov and co say the explosion was caused by an asteroid that grazed the Earth, entering the atmosphere at a shallow angle and then passing out again into space.

Continue reading “Tunguska explosion in 1908 caused by asteroid grazing Earth” »

Dec 9, 2020

Accessing the arches of chaos in the solar system for fast transport

Posted by in categories: asteroid/comet impacts, existential risks

Space manifolds form the boundaries of dynamic channels to provide fast transport to the innermost and outermost reaches of the solar system. Such features are an important element in spacecraft navigation and mission design, providing a window to the apparently erratic nature of comets and their trajectories. In a new report now published on Science Advances, Nataša Todorović and a team of researchers in Serbia and the U.S. revealed a notable and unexpected ornamental structure of manifolds in the solar system. This architecture was connected in a series of arches spreading from the asteroid belt to Uranus and beyond. The strongest manifolds were found linked to Jupiter with profound control on small bodies across a wide and previously unknown range of three-body energies. The orbits of these manifolds encountered Jupiter on rapid time-scales to transform into collisional or escaping trajectories to reach Neptune’s distance merely within a decade. In this way, much like a celestial highway, all planets generate similar manifolds across the solar system for fast transport throughout.

Navigating chaos in the solar system

In this work, Todorović et al. used fast Lyapunov indicator (FLI); a dynamic quantity used to detect chaos, to detect the presence and global structure of space manifolds. They captured the instabilities acting on orbital time scales with the sensitive and well-established numerical tool to define regions of fast transport in the solar system. Chaos in the solar system is inextricably linked to the stability or instability of manifolds forming intricate structures whose mutual interaction can enable chaotic transport. The general properties can be described relative to the planar, circular and restricted three-body problem (PCR3BP) approximating the motion of natural and artificial celestial bodies. While this concept is far from being fully understood, modern geometric insights have revolutionized spacecraft design trajectories and helped build new space-based astronomical observatories to transform our understanding of the cosmos.

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