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Astronomers: A comet fragment, not an asteroid, killed off the dinosaurs Jupiter's gravity pushed comet toward Sun; comet was ripped apart by tidal forces. Jennifer Ouellette, ArsTechnica, February 15, 2021 https://arstechnica.com/science/2021/02/astronomers-a-comet-fragment-not-an-asteroid-killed-off-the-dinosaurs/ The open access paper is: Siraj, A. and Loeb, A., Breakup of a Long-Period Comet as the Origin of the Dinosaur Extinction. Scientific Reports volume 11, Article number: 3803 (2021) https://www.nature.com/articles/s41598-021-82320-2 https://www.cfa.harvard.edu/~loeb/SLD.pdf Keep warm and safe out there Paul H.

NASA’s Voyager 2 Probe Enters Interstellar Space “For the second time in history, a human-made object has reached the space between the stars. NASA’s Voyager 2 probe now has exited the heliosphere – the protective bubble of particles and magnetic fields created by the Sun.” However: “While the probes have left the heliosphere, Voyager 1 and Voyager 2 have not yet left the solar system, and won’t be leaving anytime soon. The boundary of the solar system is considered to be beyond the outer edge of the Oort Cloud, a collection of small objects that are still under the influence of the Sun’s gravity. The width of the Oort Cloud is not known precisely, but it is estimated to begin at about 1,000 astronomical units (AU) from the Sun and to extend to about 100,000 AU. One AU is the distance from the Sun to Earth. It will take about 300 years for Voyager 2 to reach the inner edge of the Oort Cloud and possibly 30,000 years to fly beyond it.” Sooo... This illustration shows the position of NASA’s Voyager 1 and Voyager 2 probes, outside of the heliosphere, a protective bubble created by the Sun that extends well past the orbit of Pluto. Credits: NASA/JPL-Caltech The set of graphs on the left illustrates the drop in electrical current detected in three directions by Voyager 2's plasma science experiment (PLS) to background levels. They are among the key pieces of data that show that Voyager 2 entered interstellar space in November 2018. Credits: NASA/JPL-Caltech/MIT