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.

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

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.

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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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.

“We argue that the Tunguska event was caused by an iron asteroid body, which passed through the Earth’s atmosphere and continued to the near-solar orbit,” they say. If they are correct, the theory suggests Earth escaped an even larger disaster by a hair’s breadth.

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.

“Herzog tells Inverse he’s less concerned than ever that a meteorite will destroy the Earth, but that doesn’t mean we shouldn’t still be worried about our own extinction. “It may be 100 million years to go until then,” Herzog says, before adding, “within the next thousand years, we may have done such stupid things that we are not around anymore to contemplate it.” The German filmmaker also explains what asteroids reveal about the universe, why he’s never watched Rick and Morty, even though it’s a “fiendishly intelligent show,” and lists the many things that could wipe out humanity before a meteorite ever arrives.”

The legendary director discusses his new film, ‘Fireball: Visitors From Darker Worlds,’ along with Star Wars, ‘Rick and Morty,’ and working with a co-director.