The Oort Cloud Might be More Active Than We Thought

By Brian Koberlein - November 13, 2023 01:43 PM UTC | Planetary Science
Astronomers have seen meteors strike the Earth on hyperbolic trajectories for decades; they would have escaped the Solar System if our planet hadn't gotten in the way. They could have come from other solar systems, but an interstellar meteorite has never been found. Instead, these might be coming from the Oort Cloud, perturbed by a rogue planet or star passing close to the Solar System. It might be happening more often than we thought.
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If You Account for the Laniakea Supercluster, The Hubble Tension Might Be Even Larger

By Brian Koberlein - November 11, 2023 11:22 AM UTC | Cosmology
When you measure the Universe's expansion rate to relatively nearby galaxies against the expansion rate in the cosmic microwave background radiation, the numbers don't agree, and their error bars don't overlap. This is the Hubble Tension. A new paper suggests the difference might be even greater by 2-3% (1.1 km/s/Mpc) when you account for the gravitational effect from the Laniakea supercluster, which dominates the gravity in our part of the Universe.
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