Differences

This shows you the differences between two versions of the page.

--- transportation:comets [2026/07/09 23:38] – [Defense / Deflect] timb
+++ transportation:comets [2026/11/07 20:09] (current) – [Meteorite] timb
@@ Line 286: / Line 286: @@
+===== 1998 SH2 =====
+== Scientists Believed This Near-Earth Object Was an Asteroid for 28 Years. They Were Wrong ==
+The asteroid 1998 SH2 is actually not an asteroid at all.
+Passant Rabie - July 21, 2026, 7:30 am ET
+On August 28, 2025, astronomers aimed NASA’s radar system at a region of space where a near-Earth asteroid was expected to appear. Instead, the object failed to show up, leaving researchers puzzled. The unexpected no-show turned what seemed like a routine observation into a surprising case of mistaken identity.
+In a study published in Nature Astronomy, a team of scientists reveals the true identity of a near-Earth object with an apparent dual personality. Scientists had been tracking the object for 28 years, assuming it might be an asteroid. Its recent deviation from its predicted path, however, suggested something unexpected is influencing the object’s motion.
+Although previous observations of asteroid 1998 SH2 didn’t show obvious comet-like behavior, a more precise measurement of its position in the sky proved that its motion is irregular like that of a comet.
+https://gizmodo.com/scientists-thought-this-near-earth-object-was-an-asteroid-for-28-years-they-were-wrong-2000787726
@@ Line 754: / Line 771: @@
 https://gizmodo.com/dust-dinosaur-extinction-climate-simulations-chicxulub-1850985083
+== The Asteroid That Killed the Dinosaurs May Not Have Done It Exactly How We Thought ==
+Researchers identified the Chicxulub impactor as an exceptionally rare type of asteroid that wouldn't have triggered a mass extinction in the way scientists previously thought.
+Ellyn Lapointe - July 20, 2026, 11:45 am ET
+Roughly 66 million years ago, a giant asteroid slammed into what is known today as Mexico’s Yucatán Peninsula, triggering the extinction of all non-bird dinosaurs and many other species. Scientists know this thanks to a wealth of geological evidence, but a new study has them rethinking how the impact contributed to that mass extinction.
+The findings, published Friday in the journal Science Advances, suggest that the asteroid was an exceptionally rare visitor from the edge of our solar system. After analyzing samples from a thin layer of clay that the impact deposited across the globe, the researchers concluded that the impactor was a CO chondrite. This type of space rock has relatively low concentrations of volatile elements such as water, carbon, zinc, and particularly sulfur, which throws the widely accepted extinction mechanism into question.
+“It doesn’t alter our theory of what caused the extinction event—but it makes it less likely that sulphur contained in the impactor was the smoking gun,” co-author Philippe Claeys, a planetary scientist and professor at the Free University of Brussels in Belgium, said in a statement. “The fine debris thrown into the atmosphere would have [been] the primary factor.” Claeys contributed to this research as a visiting professor at the University of British Columbia.
+https://gizmodo.com/the-asteroid-that-killed-the-dinosaurs-may-not-have-done-it-exactly-how-we-thought-2000787712
+== Dinosaur-killing impact crater might have been teeming with life ==
+Hot, nutrient water might have lasted for over 5 million years after the impact.
+Elizabeth Rayne – Sep 30, 2026 2:54 PM
+About 66 million years ago, the Chicxulub asteroid smashed into Earth, kicking up tsunamis and dropping hot debris that annihilated non-avian dinosaurs and many other species. But not everything it left in its wake was destructive. This space rock hit what is now the partially submerged Yucatan Peninsula, and at the bottom of the ocean, the impact generated enough heat to create a hydrothermal system that persisted for 8 million years and may have been a hotbed of life.
+When researchers drilled for samples in the impact zone in 2016, they studied the types of rock that had formed as a result of the asteroid strike. This gave more insight into what happened in the immediate and long-term aftermath of this cataclysmic event.
+The collision was intense enough to cause deformation far beneath the surface. Subterranean effects reached 35 km (almost 22 miles) down, and included the melting an immense amount of rock. Exposure to seawater made that rock porous. As hot water seeped into the pores, a hydrothermal system formed. The hot water gushing into an isolated region of the freezing depths could have attracted microorganisms and possibly other life forms that were otherwise struggling to survive.
+More recently, another team of researchers, led by geologist and planetary scientist Annemarie Pickersgill of the SUERC Center for Isotope Sciences at the University of Glasgow, studied the rock samples for more evidence of its formation and longevity. What they found was that both the scale of this hydrothermal system and how long it lasted had previously been underestimated. It was thought to have been around for only 2 million years, but the new analysis found evidence that it remained in the depths under the Yucatán Peninsula at least four times longer than that.
+https://arstechnica.com/science/2026/09/dinosaur-killing-impact-crater-might-have-been-teeming-with-life/
@@ Line 866: / Line 911: @@
 https://science.slashdot.org/story/23/03/18/0341259/small-near-earth-asteroid-surfaces-have-few-precious-metals-study-finds
+===== Oklahoma =====
+== A Buried Oklahoma Crater Was Dated to the Wrong Era—and It Actually Lines Up With a Mass Extinction ==
+“No matter what technique we used, it was coming back to this younger signal.”
+Gayoung Lee - September 29, 2026, 12:05 pm ET
+In 1991, an oil company discovered a giant crater buried under Ames, Oklahoma. Subsequent investigations led researchers to propose the meteor responsible for the structure belonged to the many meteors that struck North America some 470 million years ago. New dating, however, challenges this account—while proposing an entirely different context for this enigmatic crater.
+According to a recently published study in Meteoritics & Planetary Science, researchers dated zircon crystals from the site and found that the Ames crater likely formed about 370 million years ago, during the Late Devonian. That represents a whopping 100-million-year gap with the Ordovician meteor event, when Earth saw a large increase in meteor events roughly 467 million years ago. Importantly, this now temporally places the Ames crater within another significant period in geological history: the Frasnian–Famennian mass extinction, which drastically reshaped Earth’s marine ecosystems.
+“No matter what technique we used, it was coming back to this younger signal,” Elizabeth Catlos, the study’s lead author and an Earth scientist at the University of Texas at Austin, said in a statement. “With this research, we’re basically taking a major pawn out of the Ordovician Meteor Event and dumping it into the Frasnian-Famennian event, and saying, ‘This is where this impact belongs.’”
+https://gizmodo.com/a-buried-oklahoma-crater-was-dated-to-the-wrong-era-and-it-actually-lines-up-with-a-mass-extinction-2000818870
@@ Line 1123: / Line 1188: @@
 https://gizmodo.com/pieces-asteroid-bennu-smithsonian-nasa-osiris-rex-1850963488
+== Asteroid Bennu Came From an Unexpected Corner of the Solar System ==
+A new study pinpoints Bennu's birthplace to a specific zone between the inner and outer solar system.
+Passant Rabie - September 29, 2026, 9:10 am ET
+Six years after NASA’s OSIRIS-REx spacecraft reached out and snagged a sample from the asteroid Bennu, scientists may finally have an answer to a fundamental question: Where did this ancient space rock come from?
+A new study traces Bennu’s history to a region near the boundary between the inner and outer solar system—a finding that offers a rare glimpse into the chaotic environment where the planets were taking shape billions of years ago. By reconstructing Bennu’s journey through the early solar system, researchers can begin to piece together how material from different regions mixed and moved as planets like Earth formed.
+“Bennu may offer our best glimpse of the original mix of chemical elements from which the terrestrial planets were ultimately built,” Maria Schönbächler, professor of isotope geochemistry at ETH Zurich and lead author of the study published in Science Advances, said in a statement.
+https://gizmodo.com/asteroid-bennu-came-from-an-unexpected-corner-of-the-solar-system-2000818415
@@ Line 1512: / Line 1593: @@
 https://www.chemistryworld.com/news/meteorite-200-times-larger-than-one-that-killed-dinosaurs-reset-early-life/4020391.article
+== Amateur Astronomer Discovers Ancient Meteorite Impact Using Google Maps ==
+Scientists confirmed that the crater dates back around 390 million years ago.
+Passant Rabie - July 28, 2026, 9:25 am ET
+Joël Lapointe was casually browsing Google Maps, planning hiking routes for an upcoming camping trip, when he stumbled upon an unusual indentation near Marsal Lake in Quebec. As an amateur astronomer, Lapointe recognized that the large pit may be the site of a meteorite impact that left a scar on the terrain. Scientists just confirmed that he was right.
+Researchers announced the existence of a large crater in the Côte-Nord region of Quebec, which dates back to around 390 million years ago, the Canadian Broadcasting Corporation (CBC) reported. Following Lapointe’s initial discovery in 2024, a team of geologists set out to examine the impact site and were able to verify that a meteorite did in fact smash into Earth at this particular point.
+The team’s research will be presented at the annual congress of the Meteoritical Society, which will be held on August 9 to 14 in Frankfurt, Germany.
+https://gizmodo.com/amateur-astronomer-discovers-ancient-meteorite-impact-using-google-maps-2000791283
+== Scientists Find Rare Meteorite From Mars With Signs of Ancient Water ==
+Posted by EditorDavid on Saturday November 07, 2026 11:00AM
+"I didn't think a rock like this existed on Earth," a geologist at the Lunar and Planetary Institute in Texas told the Washington Post. It looks like a polished rock, dark brown with a clay-colored stripe — but it's actually one of the oldest Mars meteorites ever found, blasted by an impact from the surface of Mars billions of years ago:
+<blockquote>
+Technically speaking it's a collection of eight rock fragments, the largest of which is about the size of a fist. Nearly two pounds of the meteorite was discovered in the Sahara in Mali in 2022, and most is now held by a museum in Maine. Within two years, an initial examination determined the meteorite hailed from Mars; scientists are now finally digging deeper, with stunning results.
+It offers records of "interactions of water and rock and maybe even an imprint of the Martian atmosphere as it was losing water," says Lee Saper, co-author of a new paper recently published in Science. "It was only after we started looking closely that we realized this meteorite is really unique," said Yang Liu of NASA's Jet Propulsion Laboratory in Southern California, the lead author of a new paper published in Science. "One of the paper's reviewers called it a Rosetta Stone for Mars."
+</blockquote>
+https://science.slashdot.org/story/26/11/07/0628228/scientists-find-rare-meteorite-from-mars-with-signs-of-ancient-water