Nicole Sharp
@admin@fyfluiddynamics.com  ·  activity timestamp 6 days ago

Glacier Timelines

"The Rhone Glacier" by Fabian Oefner.

Over the past 150 years, Switzerland’s glaciers have retreated up the alpine slopes, eaten away by warming temperatures induced by industrialization. But such changes can be difficult for people to visualize, so artist Fabian Oefner set out to make these changes more comprehensible. These photographs — showing the Rhone and Trift glaciers — are the result. Oefner took the glacial extent records dating back into the 1800s and programmed them into a drone. Lit by LED, the drone flew each year’s profile over the mountainside, with Oefner capturing the path through long-exposure photography. When all the paths are combined, viewers can see the glacier’s history written on its very slopes. The effect is, fittingly, ghost-like. We see a glimpse of the glacier as it was, laid over its current remains. (Image credit: F. Oefner; video credit: Google Arts and Culture)

https://www.youtube.com/watch?v=_EJrCXGQuFg

#climateChange #flowVisualization #fluidDynamics #fluidsAsArt #glacier #pathlines #physics #science #timelapse
Nicole Sharp
@admin@fyfluiddynamics.com  ·  activity timestamp 6 days ago

Glacier Timelines

"The Rhone Glacier" by Fabian Oefner.

Over the past 150 years, Switzerland’s glaciers have retreated up the alpine slopes, eaten away by warming temperatures induced by industrialization. But such changes can be difficult for people to visualize, so artist Fabian Oefner set out to make these changes more comprehensible. These photographs — showing the Rhone and Trift glaciers — are the result. Oefner took the glacial extent records dating back into the 1800s and programmed them into a drone. Lit by LED, the drone flew each year’s profile over the mountainside, with Oefner capturing the path through long-exposure photography. When all the paths are combined, viewers can see the glacier’s history written on its very slopes. The effect is, fittingly, ghost-like. We see a glimpse of the glacier as it was, laid over its current remains. (Image credit: F. Oefner; video credit: Google Arts and Culture)

https://www.youtube.com/watch?v=_EJrCXGQuFg

#climateChange #flowVisualization #fluidDynamics #fluidsAsArt #glacier #pathlines #physics #science #timelapse
grobi
@grobi@defcon.social  ·  activity timestamp 2 weeks ago

Asteroid Watch: Keeping an Eye on Near-Earth Objects

Managed for NASA at the Jet Propulsion Laboratory, the Center for Near Earth Object Studies (CNEOS) accurately characterizes the orbits of all known near-Earth objects, predicts their close approaches with Earth, and makes comprehensive impact hazard assessments in support of the agency’s Planetary Defense Coordination Office at NASA Headquarters in Washington.

Near-Earth objects are asteroids and comets with orbits that bring them to within 120 million miles (195 million kilometers) of the Sun, which means they can circulate through the Earth’s orbital neighborhood. Most near-Earth objects are asteroids that range in size from about 10 feet (a few meters) to nearly 25 miles (40 kilometers) across.

The orbit of each object is computed by finding the elliptical path through space that best fits all the available observations, which often span many orbits over many years or decades. As more observations are made, the accuracy of an object's orbit improves dramatically, and it becomes possible to predict where an object will be years or even decades into the future – and whether it could come close to Earth.

The majority of near-Earth objects have orbits that don’t bring them very close to Earth, and therefore pose no risk of impact, but a small fraction of them – called potentially hazardous asteroids – require more attention. These objects are defined as asteroids that are more than about 460 feet (140 meters) in size with orbits that bring them as close as within 4.6 million miles (7.5 million kilometers) of Earth’s orbit around the Sun. CNEOS continuously monitors all known near-Earth objects to assess any impact risk they may pose. [...]
Read more:
https://www.jpl.nasa.gov/asteroid-watch/

#space #earth #science #astronomy #physics #tech #defense#NASA#ESA

The orbital positions of near-Earth objects come from the databases of the Minor Planet Center, the internationally recognized clearinghouse for small-body position measurements. This data is collected by observatories around the world, including significant contributions from amateur observers. The vast majority of asteroid-tracking data, however, is collected by large NASA-funded observatories (such as Pan-STARRS, the Catalina Sky Survey, NASA’s NEOWISE mission and, in the future, NEO Surveyor). Planetary radar projects (including JPL’s Goldstone Solar System Radar Group) are another key component of NASA’s NEO Observations Program. The Center for Near-Earth Object Studies is home of the Sentry impact-monitoring system, which continuously performs long-term analyses of possible future orbits of hazardous asteroids. There is currently no known significant threat of impact for the next hundred years or more. The Center also maintains the Scout system that continually monitors brand-new potential near-Earth object detections, even before they have been confirmed as new discoveries, to see whether any of these generally very small asteroids might pose a threat of short-term (possibly imminent) impact. Credit: NASA/JPL-Caltech
The orbital positions of near-Earth objects come from the databases of the Minor Planet Center, the internationally recognized clearinghouse for small-body position measurements. This data is collected by observatories around the world, including significant contributions from amateur observers. The vast majority of asteroid-tracking data, however, is collected by large NASA-funded observatories (such as Pan-STARRS, the Catalina Sky Survey, NASA’s NEOWISE mission and, in the future, NEO Surveyor). Planetary radar projects (including JPL’s Goldstone Solar System Radar Group) are another key component of NASA’s NEO Observations Program. The Center for Near-Earth Object Studies is home of the Sentry impact-monitoring system, which continuously performs long-term analyses of possible future orbits of hazardous asteroids. There is currently no known significant threat of impact for the next hundred years or more. The Center also maintains the Scout system that continually monitors brand-new potential near-Earth object detections, even before they have been confirmed as new discoveries, to see whether any of these generally very small asteroids might pose a threat of short-term (possibly imminent) impact. Credit: NASA/JPL-Caltech
grobi
@grobi@defcon.social  ·  activity timestamp 2 weeks ago

The Cretaceous–Paleogene (K–Pg) extinction event, formerly known as the Cretaceous-Tertiary (K–T) extinction event, was the mass extinction of three-quarters of the plant and animal species on Earth approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs. Most other tetrapods weighing more than 25 kg (55 lb) also became extinct, with the exception of some ectothermic species such as sea turtles and crocodilians. It marked the end of the Cretaceous period, and with it the Mesozoic era, while heralding the beginning of the current geological era, the Cenozoic Era.
[...]

As originally proposed in 1980 by a team of scientists led by Luis Alvarez and his son Walter, it is now generally thought that the K–Pg extinction was caused by the impact of a massive asteroid 10 to 15 km (6 to 9 mi) wide, 66 million years ago causing the Chicxulub impact crater, which devastated the global environment, mainly through a lingering impact winter which halted photosynthesis in plants and plankton. The impact hypothesis, also known as the Alvarez hypothesis, was bolstered by the discovery of the 180 km (112 mi) Chicxulub crater in the Gulf of Mexico's Yucatán Peninsula in the early 1990s, which provided conclusive evidence that the K–Pg boundary clay represented debris from an asteroid impact. The fact that the extinctions occurred simultaneously provides strong evidence that they were caused by the asteroid. A 2016 drilling project into the Chicxulub peak ring confirmed that the peak ring comprised granite ejected within minutes from deep in the earth, but contained hardly any gypsum, the usual sulfate-containing sea floor rock in the region: the gypsum would have vaporized and dispersed as an aerosol into the atmosphere, causing longer-term effects on the climate and food chain.
[...]
Read more
https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_extinction_event

#space #earth #asteroids #science #history #astronomy #physics #tech #defense#NASA#ESA

Visualization of asteroid impact that killed dinosaurs 65 million years ago, based on accurate research and scientific fact. Created by Radek Michalik (writetoradek@gmail.com) at the Science Institute of Columbia College Chicago. Video Credit Radek Michalik
Visualization of asteroid impact that killed dinosaurs 65 million years ago, based on accurate research and scientific fact. Created by Radek Michalik (writetoradek@gmail.com) at the Science Institute of Columbia College Chicago. Video Credit Radek Michalik
grobi
@grobi@defcon.social  ·  activity timestamp 2 weeks ago

TOPIC> About Planetary Defense

2023 June 30

Orbits of Potentially Hazardous Asteroids
* Illustration Credit: NASA, JPL-Caltech
https://www.nasa.gov/
https://www.jpl.nasa.gov/

Explanation:
Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth. Pictured here are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon. Although none of them will strike the Earth in the next 100 years -- not all PHAs have been discovered, and past 100 years, many orbits become hard to predict. Were an asteroid of this size to impact the Earth, it could raise dangerous tsunamis, for example. To investigate Earth-saving strategies, NASA successfully tested the Double Asteroid Redirection Test (DART) mission in 2022. Of course, rocks and ice bits of much smaller size strike the Earth every day, usually pose no danger, and sometimes create memorable fireball and meteor displays.
https://photojournal.jpl.nasa.gov/catalog/PIA17041
https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_extinction_event
https://web.archive.org/web/20161210142717/http://nss.org/resources/library/planetarydefense/2000-ReportOfTheTaskForceOnPotentiallyHazardousNearEarthObjects-UK.pdf
https://en.wikipedia.org/wiki/List_of_asteroid_close_approaches_to_Earth

https://www.jpl.nasa.gov/

#space #earth #astrophotography #photography #science #astronomy #physics #tech #defense#NASA#ESA

2023 June 30 A dark background is filled with many light-blue ellipses. Toward the center, near circles that are labelled as the orbits of the inner planets of our Solar System are drawn. Orbits of Potentially Hazardous Asteroids * Illustration Credit: NASA, JPL-Caltech Explanation: Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth. Pictured here are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon. Although none of them will strike the Earth in the next 100 years -- not all PHAs have been discovered, and past 100 years, many orbits become hard to predict. Were an asteroid of this size to impact the Earth, it could raise dangerous tsunamis, for example. To investigate Earth-saving strategies, NASA successfully tested the Double Asteroid Redirection Test (DART) mission in 2022. Of course, rocks and ice bits of much smaller size strike the Earth every day, usually pose no danger, and sometimes create memorable fireball and meteor displays. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
2023 June 30 A dark background is filled with many light-blue ellipses. Toward the center, near circles that are labelled as the orbits of the inner planets of our Solar System are drawn. Orbits of Potentially Hazardous Asteroids * Illustration Credit: NASA, JPL-Caltech Explanation: Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth. Pictured here are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon. Although none of them will strike the Earth in the next 100 years -- not all PHAs have been discovered, and past 100 years, many orbits become hard to predict. Were an asteroid of this size to impact the Earth, it could raise dangerous tsunamis, for example. To investigate Earth-saving strategies, NASA successfully tested the Double Asteroid Redirection Test (DART) mission in 2022. Of course, rocks and ice bits of much smaller size strike the Earth every day, usually pose no danger, and sometimes create memorable fireball and meteor displays. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
2023 June 30 A dark background is filled with many light-blue ellipses. Toward the center, near circles that are labelled as the orbits of the inner planets of our Solar System are drawn. Orbits of Potentially Hazardous Asteroids * Illustration Credit: NASA, JPL-Caltech Explanation: Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth. Pictured here are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon. Although none of them will strike the Earth in the next 100 years -- not all PHAs have been discovered, and past 100 years, many orbits become hard to predict. Were an asteroid of this size to impact the Earth, it could raise dangerous tsunamis, for example. To investigate Earth-saving strategies, NASA successfully tested the Double Asteroid Redirection Test (DART) mission in 2022. Of course, rocks and ice bits of much smaller size strike the Earth every day, usually pose no danger, and sometimes create memorable fireball and meteor displays. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
Anke
Dane 🇮🇪 ☮️🕉️⚛️☸️
Anke and 1 other boosted
John Cormier 🇨🇦
@johncormier@mstdn.ca  ·  activity timestamp 2 weeks ago

Hi everyone, figured it was time to write a new introduction. I’m John, and I live on the east coast of Canada. I’m a 50-something physicist who invented a laser technology to detect diseases using exhaled breath in addition to some holographic technologies. I love research but the best part of my career has been mentoring promising young scientists, engineers, and founders. I have a wide variety of interests that include music, art, science, health, photography, books, reading, video games, biking, hiking, gardening, and much more. I am a lifelong feminist and ally. When I came to Mastodon from Twitter in the fall of 2022, I had no idea that I was actually autistic. If you made it this far, please wave or say hello! #introduction #actuallyautistic #physics #science#Canada #startups #founder #mentoring #books
John Cormier 🇨🇦
@johncormier@mstdn.ca  ·  activity timestamp 2 weeks ago

Hi everyone, figured it was time to write a new introduction. I’m John, and I live on the east coast of Canada. I’m a 50-something physicist who invented a laser technology to detect diseases using exhaled breath in addition to some holographic technologies. I love research but the best part of my career has been mentoring promising young scientists, engineers, and founders. I have a wide variety of interests that include music, art, science, health, photography, books, reading, video games, biking, hiking, gardening, and much more. I am a lifelong feminist and ally. When I came to Mastodon from Twitter in the fall of 2022, I had no idea that I was actually autistic. If you made it this far, please wave or say hello! #introduction #actuallyautistic #physics #science#Canada #startups #founder #mentoring #books
Steven Saus [he/him]
@StevenSaus@faithcollapsing.com  ·  activity timestamp 3 weeks ago

(14 Jul) Merger of two massive black holes is one for the record books

The event resulted in a new black hole with a mass 225 times larger than our Sun.

https://s.faithcollapsing.com/tc4bz
Archive: ais: https://archive.md/wip/IvH8C ia: https://s.faithcollapsing.com/7j466

#astronomy #astrophysics #black-hole-mergers #black-holes #gravitational-waves #ligo-virgo-kagra #physics #science
Steven Saus [he/him]
@StevenSaus@faithcollapsing.com  ·  activity timestamp 3 weeks ago

(14 Jul) Merger of two massive black holes is one for the record books

The event resulted in a new black hole with a mass 225 times larger than our Sun.

https://s.faithcollapsing.com/tc4bz
Archive: ais: https://archive.md/wip/IvH8C ia: https://s.faithcollapsing.com/7j466

#astronomy #astrophysics #black-hole-mergers #black-holes #gravitational-waves #ligo-virgo-kagra #physics #science

Paul
Paul boosted
Jon Sullivan
@joncounts@mastodon.nz  ·  activity timestamp last month

The new science video from #Veritasium is wild and worth a watch.

It's about Braess’s Paradox, which I'd not heard of before, but it shows up in all sorts of places, including traffic planning.

The video includes a fantastic couple of examples of why car traffic times can sometimes go up when more roads are built. That's not the usual case of more people using the roads. Instead, with the same number of drivers, adding a road makes everyone's journey time slower.

This example might seem a bit contrived but the video also cites a study where the equivalent did happen when a busy street in New York City was closed off, and travel times for everyone paradoxically went down.

Physics and maths are wonderfully counterintuitive sometimes.

https://www.youtube.com/watch?v=-QTkPfq7w1A

#physics#SciComm #transport #traffic

In this modified road layout, the city has built a short 1 minute section of motorway connecting the two city street sections of route together. The shortest travel distance is now going straight down the midde, but since everyone chooses to take that route, the city street sections become slower and travel time *increases* from 35 minutes to 41 minutes. If a car chose to take one of the side routes it would take even longer (45 minutes) as they would end up on a clogged city street with everyone else. (Do watch the video for a much clearer explanation.) Screenshot from https://www.youtube.com/watch?v=-QTkPfq7w1A
In this modified road layout, the city has built a short 1 minute section of motorway connecting the two city street sections of route together. The shortest travel distance is now going straight down the midde, but since everyone chooses to take that route, the city street sections become slower and travel time *increases* from 35 minutes to 41 minutes. If a car chose to take one of the side routes it would take even longer (45 minutes) as they would end up on a clogged city street with everyone else. (Do watch the video for a much clearer explanation.) Screenshot from https://www.youtube.com/watch?v=-QTkPfq7w1A
In this modified road layout, the city has built a short 1 minute section of motorway connecting the two city street sections of route together. The shortest travel distance is now going straight down the midde, but since everyone chooses to take that route, the city street sections become slower and travel time *increases* from 35 minutes to 41 minutes. If a car chose to take one of the side routes it would take even longer (45 minutes) as they would end up on a clogged city street with everyone else. (Do watch the video for a much clearer explanation.) Screenshot from https://www.youtube.com/watch?v=-QTkPfq7w1A
A diagram showing two road routes from start to end. Each route contains two sections. One section is wide motorway where travel time is always 25 minutes and not related to the number of cars (within the volumes of this example). The other section is a narrow city street where travel time *is* proportional to the number of cars (one extra minute for each 100 cars). In this example, if there are 2000 cars, and half take each route, then the journey time is 25 minutes + 10 minutes = 35 minutes. This is a screenshot from https://www.youtube.com/watch?v=-QTkPfq7w1A
A diagram showing two road routes from start to end. Each route contains two sections. One section is wide motorway where travel time is always 25 minutes and not related to the number of cars (within the volumes of this example). The other section is a narrow city street where travel time *is* proportional to the number of cars (one extra minute for each 100 cars). In this example, if there are 2000 cars, and half take each route, then the journey time is 25 minutes + 10 minutes = 35 minutes. This is a screenshot from https://www.youtube.com/watch?v=-QTkPfq7w1A
A diagram showing two road routes from start to end. Each route contains two sections. One section is wide motorway where travel time is always 25 minutes and not related to the number of cars (within the volumes of this example). The other section is a narrow city street where travel time *is* proportional to the number of cars (one extra minute for each 100 cars). In this example, if there are 2000 cars, and half take each route, then the journey time is 25 minutes + 10 minutes = 35 minutes. This is a screenshot from https://www.youtube.com/watch?v=-QTkPfq7w1A