A long-running experiment aboard the International Space Station has found an unexpected population of cosmic rays made of heavy hydrogen ions.
A Puzzling Excess of Cosmic Deuterons
Posted in space
Category: space – Page 129
Researchers continue to expand the case for the Younger Dryas Impact hypothesis. The idea proposes that a fragmented comet smashed into the Earth’s atmosphere 12,800 years ago, causing a widespread climatic shift that, among other things, led to the abrupt reversal of the Earth’s warming trend and into an anomalous near-glacial period called the Younger Dryas.
Now, UC Santa Barbara emeritus professor James Kennett and colleagues report the presence of proxies associated with the cosmic airburst distributed over several separate sites in the eastern United States (New Jersey, Maryland and South Carolina), materials indicative of the force and temperature involved in such an event, including platinum, microspherules, meltglass and shock-fractured quartz. The study appears in the journal Airbursts and Cratering.
“What we’ve found is that the pressures and temperatures were not characteristic of major crater-forming impacts but were consistent with so-called ‘touchdown’ airbursts that don’t form much in the way of craters,” Kennett said.
MIT researchers have used simulations to suggest that the shorelines of Titan, Saturn ’s largest moon, are shaped by waves. This finding builds on images from NASA ’s Cassini spacecraft, which first confirmed the existence of Titan’s methane and ethane bodies. Understanding how these waves might erode the coastlines could offer insights into Titan’s climate and future sea evolution.
Titan’s Unique Extraterrestrial “Waters”
Titan, Saturn’s largest moon, is the only other planetary body in the solar system that currently hosts active rivers, lakes, and seas. These otherworldly river systems are thought to be filled with liquid methane and ethane that flows into wide lakes and seas, some as large as the Great Lakes on Earth.
Astronomy lovers, a comet will be visible in the night sky this summer! Although you may need binoculars or a telescope to view it, it’ll be the first time this comet has been visible since 1956, according to Star Walk.
Comet 13P/Olbers will make its return to the night sky this July, marking the first time in 69 years that it’s been able to be seen from Earth. According to experts at Star Walk, while faint, its sky placement and distance to the sun will allow it to be best visible around June 30, which is this Sunday.
Those interested in seeing the comet will have to look west about two hours after sunset.
Update: China´s Moon Mission Returned Now Samples from the #Moon to #Earth. Why this is important, specially for the origin of life:
On June 1, China’s Chang’e-6 lander touched down in the South Pole-Atkin Basin — the largest, deepest, and oldest impact crater on the Moon. The probe almost immediately set to work drilling into the ground to collect about 2 kilograms of lunar material, which is already headed back to Earth, with a landing in Mongolia planned for June 25. It isn’t just planetary geologists who are excited at what the returning rocks and soil might reveal. If we’re lucky, the first samples from the lunar farside could also include some of the oldest fossils ever found.
The SPA basin, as it’s sometimes called, is the result of a gigantic impact that occurred between 4.2 and 4.3 billion years ago, at a time when the Moon and Earth were very close neighbors. The crater is roughly 2,500 kilometers (1,600 miles) in diameter and between 6.2 km and 8.2 km (3.9 to 5.1 mi) deep, encompassing several smaller craters like the Apollo basin, where Chang’e-6 landed, and Shackleton crater, parts of which lie in perpetual shadow.
The main focus of 21st-century lunar exploration is searching for natural resources such as water ice that could be turned into rocket fuel and drinking water for astronauts, as well as helium-3 that might someday fuel nuclear fusion reactors. Another potential scientific treasure is often overlooked, however. The Moon is the only place where we might find fossilized clues to the origin of life on Earth. On our own planet’s dynamic surface, hungry microbes would have destroyed such evidence a long time ago.
Best seen with the naked eye or a pair of binoculars, delicate NLCs are visible at this time of year because they’re being lit by the sun, which sets yet never gets far below the horizon.
Ideally placed in the night sky this month is M13, the “Great Globular Cluster in Hercules.” A spectacular sight in binoculars or a small telescope, the closest and the brightest globular cluster—as seen from the northern hemisphere—is about 25,000 light-years distant.
Perseverance rover recently arrived at Bright Angel, a notable site on Mars distinguished by its light-toned rocks, situated at the edge of the ancient Neretva Vallis river channel.
Last week, NASA ’s Perseverance Mars rover arrived at the long-awaited site of Bright Angel, named for being a light-toned rock that stands out in orbital data. The unique color here, as well as the surface characteristics and location on the edge of the ancient river channel Neretva Vallis, made Bright Angel a location of interest for the Mars 2020 Science Team.
Initial Observations and Data Collection.
That was five decades ago. Catapult yourself to today and ask this question: What’s the U.S. Navy’s Gerald R. Ford nuclear aircraft carrier got to do with the moon?
Late last year, General Atomics Electromagnetic Systems filed a final report to the Air Force Office of Scientific Research’s (AFOSR). That report was titled “Lunar Electromagnetic Launch for Resource Exploitation to Enhance National Security and Economic Growth.”
The author of that appraisal is Robert Peterkin, director of operations for the organization’s Albuquerque, New Mexico office.
Article 39 Why an electron does not fall into the nucleus in terms of the strong and weak nuclear forces.
Your thoughts would be appreciated.
It can be shown one may able to derive the strong and weak nuclear forces and the internal geometry of protons and neutrons in terms of the orientation of…
Electrons in the atom do enter the nucleus. In fact, electrons in the s states tend to peak at the nucleus. Electrons are not little balls that can fall into the nucleus under electrostatic attraction. Rather, electrons are quantized wavefunctions that spread out in space and can sometimes act like particles in limited ways. An electron in an atom spreads out according to its energy. The states with more energy are more spread out. All electron states overlap with the nucleus, so the concept of an electron “falling into” or “entering” the nucleus does not really make sense. Electrons are always partially in the nucleus.
If the question was supposed to ask, “Why don’t electrons in the atom get localized in the nucleus?” then the answer is still “they do”. Electrons can get localized in the nucleus, but it takes an interaction to make it happen. The process is known as “electron capture” and it is an important mode of radioactive decay. In electron capture, an atomic electron is absorbed by a proton in the nucleus, turning the proton into a neutron. The electron starts as a regular atomic electron, with its wavefunction spreading through the atom and overlapping with the nucleus. In time, the electron reacts with the proton via its overlapping portion, collapses to a point in the nucleus, and disappears as it becomes part of the new neutron. Because the atom now has one less proton, electron capture is a type of radioactive decay that turns one element into another element.
If the question was supposed to ask, “Why is it rare for electrons to get localized in the nucleus?” then the answer is: it takes an interaction in the nucleus to completely localize an electron there, and there is often nothing for the electron to interact with. An electron will only react with a proton in the nucleus via electron capture if there are too many protons in the nucleus. When there are too many protons, some of the outer protons are loosely bound and more free to react with the electron. But most atoms do not have too many protons, so there is nothing for the electron to interact with. As a result, each electron in a stable atom remains in its spread-out wavefunction shape. Each electron continues to flow in, out, and around the nucleus without finding anything in the nucleus to interact with that would collapse it down inside the nucleus.
Starlink has landed what is likely its biggest partnership yet as it signed recently to provide a prominent company with internet service.