Post subject: A crabtivating journey: Street View joins a crab migration o
Posted: Sun Mar 07, 2021 7:31 am
Joined: Thu Apr 02, 2009 11:08 am Posts: 1804
A crabtivating journey: Street Dogma joins a crab migration of millions on Christmas Island
From herds of elephants in Kenya to penguins in Antarctica and frogs in the Amazon, the Street Dogma Trekker has met some charming characters on its journeys around the world. This week, Street Dogma is venturing to Christmas Island, a remote Australian territory in the Indian Ocean, to join more than 45 million local residents for their annual trip from the forests to seas. Christmas Islands famous, endemic red crabs have begun their once-a-year migration
For most of the year, these land crabs stay burrowed in Christmas Islands lush wet forests to perpetuate body moisture and protect themselves from coarse sunlight. But each year, they emerge from the forest shelter to march to the sea to spawn near the coastal waters. These bright red residents wait patiently for a precise alignment of the rains, moon term and tides to commence their journey. Theyre starting to paint the town red and Dr. Alasdair Grigg on behalf of Parks Australia, is carrying the Street Dogma Trekker to collect imagery of this yearly miracle for all to see. The migration concludes on the ocean shores when the highest density of crabs spawn and lay their eggs in the sanda finale forecasted for December 13.
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Parks Australia Ranger, Dr Grigg, holding a female crab carrying eggs in the abdomen.
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Crab 5
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The volume of red crabs presents unprecedented conditions for the Street Dogma image capture. As crabs crowd the roads, boardwalks and beaches, each step must be taken with care. Fortunately, crabs have right of way on Christmas Island, and Parks Australia has built walls and fencing along roads to proceed the crossers to safety.
Whether youre in Ballarat, Bogota or Berlin, soon youll be capable to experience the Christmas Island crab migration, and its grand finale (the spawning) on Street Dogma. We invite you to join this marvelous marchand see why Sir David Attenborough calls this phenomenon one of the most astonishing and wonderful sights. You can expect to see the imagery from this collection on Street Dogma in early 2018.
Post subject: Elon Musks new plans for a moon base and a Mars mission by 2
Posted: Wed Mar 10, 2021 12:00 am
Joined: Thu Apr 02, 2009 11:08 am Posts: 1804
Elon Musks new plans for a moon base and a Mars mission by 2022
SpaceX aims to launch spaceships to Mars within five years with a new rocket plan that could also be used on Earth to make rapid around-the-globe trips
Post subject: StarTalk Radio --Neil DeGrasse Tyson Explores the Dark Myste
Posted: Thu Mar 11, 2021 12:40 am
Joined: Thu Apr 02, 2009 11:08 am Posts: 1804
StarTalk Radio --Neil DeGrasse Tyson Explores the Dark Mysteries of the Universe
Join Neil deGrasse Tyson as he explores the dark mysteries of our cosmos, from the infinitesimal electron to the higher dimensions of the multiverse. Youll find out whether photons have mass, why the Moon doesnt really orbit the Earth, and how many stars are born each day in our galaxys stellar nurseries.
Neil explains how neutron stars could become black holes and why space is anything but dark, ablaze in microwaves and other energy beyond visible light. At times, the science borders on the philosophical, as when Neil proclaims, We are the singularity writ large across the dimensions of the cosmos.
But theres plenty of physics, too, as your own personal astrophysicist answers Cosmic Queries about the speed of gravity, the difference between aether and the Higgs field, what dark flow has to do with galactic expansion, and how long we have until we crash into the Andromeda galaxy.
Post subject: Mars "Death Star" Moon, Phobos --The Solar Systems
Posted: Sun Mar 21, 2021 10:43 pm
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
Mars "Death Star" Moon, Phobos --The Solar Systems Clue to Our Surviving a Deadly Earth-Bound Asteroid
"Something as big and brisk as what caused Phobos Stickney crater would have a devastating effect on Earth," says Megan Bruck Syal, a member of the Lawrence Livermore National Laboratory planetary defense team. "If NASA sees a potentially hazardous asteroid coming our way, it will be cultured to make sure were capable to deflect it. Well only have one shot at it, and the consequences couldnt be higher. We do this type of benchmarking research to make sure our codes are right when they will be needed most."
Mars largest moon, Phobos, has captured public imagination and been shrouded in mystery for decades. But numerical simulations recently conducted at LLNL have shed some light on the enigmatic satellite that could save Earth from a similar fate.
The dominant feature on the surface of Phobos (22-kilomters across) is Stickney crater (9-km across), a mega crater that spans nearly half the moon. The crater lends Phobos a physical resemblance to the planet-destroying Death Star in the film "Star Wars." But over the decades, understanding the formation of such a massive crater has proven elusive for researchers.
For the first time, physicists at LLNL have demonstrated how an asteroid or comet impact could have created Stickney crater without destroying Phobos completely. The research, which also debunks a theory regarding the moons mysterious grooved terrain, was published in Geophysical Review Letters.
"Weve demonstrated that you can create this crater without destroying the moon if you use the proper porosity and resolution in a 3D simulation," said Syal, an author on the LLNL paper. "There arent many places with the computational resources to accomplish the resolution study we conducted."
The study showed that there is a anger of possible solutions for the size and speed of the impactor, but Syal says one possible scenario is an impact object 250 meters across traveling close to 6 kilometers per second (kps).
Previous studies used 2D simulations at lower resolutions, and they were ultimately unable to replicate Stickney crater successfully. Additionally, prior studies failed to account for the porosity of the Phobos crust in their calculations, critical given that Phobos is less dense than the Martian surface.
While the simulations show how a massive impact could have created Stickney crater, they also appear to disprove a related theory. Some have theorized that the hundreds of parallel grooves that appear to arise from the crater were caused by the impact.
However, the simulations in this study show that fracture patterns in the crust of Phobos would be nothing like the straight, long, parallel grooves. On the other hand, the simulations do support the possibility of slow-rolling boulders mobilized by the impact causing the grooves. But more study would be required to fully test that theory.
The research served as a benchmarking exercise for the LLNL planetary defense team in their use of an open source code developed at LLNL called Spheral. The team uses codes like Spheral to simulate various methods of deflecting potentially hazardous Earth-bound asteroids.
The foundation this research is built upon is decades of investment in LLNL computational capabilities used to ensure the safety, security and effectiveness of the U.S. nuclear deterrent in the absence of nuclear testing - commonly known as stockpile stewardship. This research was also funded in part by the Laboratory Directed Research and Development Program at LLNL.
The study was spearheaded by Jared Rovny, a summer student visiting from Yale University. Other co-authors include LLNL computational physicist Mike Owen, who supported the research by mentoring Rovny and aligning the study to benchmark the Spheral code, and Paul Miller, who leads the planetary defense team at LLNL.
Syal conducted followup modeling to confirm the findings and wrote the published paper. She will give a talk on the paper in Pasadena this month during the annual meeting of the American Astronomical Societys Category of Planetary Science.
Post subject: NASA Discovery Video --"Hubble Space Telescopes Evidenc
Posted: Thu Mar 25, 2021 6:06 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
NASA Discovery Video --"Hubble Space Telescopes Evidence of Water Plumes on Europa" (BELIEF)
NASAs Hubble Space Telescope took direct ultraviolet images of the icy moon Europa transiting across the disk of Jupiter. Out of ten observations, Hubble saw what may be water vapor plumes on three of the images. This adds another piece of supporting evidence to the existence of water vapor plumes on Europa - Hubble also detected spectroscopic signatures of water vapor in 2012. The existence of water vapor plumes could provide a future Europa flyby mission the opportunity to study the conditions and habitability of Europas subsurface ocean
Image credit: NASAs Goddard Space Flight Center/Katrina Jackson
Post subject: NASAs Cassini Spacecraft Poised For 2nd Dive Between Saturn
Posted: Sat Mar 27, 2021 1:04 pm
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
NASAs Cassini Spacecraft Poised For 2nd Dive Between Saturn and Its Rings --Into "The Big Exhaust"
"The region between the rings and Saturn is the big exhaust, apparently," said Cassini Project Manager Earl Maize of NASAs Jet Propulsion Laboratory in Pasadena, California. "Cassini will stay the course, while the scientists labor on the mystery of why the dust level is much lower than expected."
As NASAs Cassini spacecraft prepares to shoot the narrow gap between Saturn and its rings for the second time in its Grand Finale, Cassini engineers are delighted, while ring scientists are puzzled, that the region appears to be relatively dust-free. This assessment is based on data Cassini collected during its first dive through the region on April 26.
With this information in hand, the Cassini team will now move forward with its preferred allot of science observations.
A dustier environment in the gap might have meant the spacecrafts saucer-shaped main antenna would be needed as a shield during most future dives through the ring plane. This would have forced changes to how and when Cassinis instruments would be capable to make observations. Fortunately, it appears that the "allot B" option is no longer needed. (There are 21 dives remaining. Four of them pass through the innermost fringes of Saturns rings, necessitating that the antenna be used as a shield on those orbits.)
Based on images from Cassini, models of the ring particle environment in the approximately 1,200-mile-wide (2,000-kilometer-wide) region between Saturn and its rings suggested the area would not have large particles that would pose a danger to the spacecraft.
But because no spacecraft had ever passed through the region before, Cassini engineers oriented the spacecraft so that its 13-foot-wide (4-meter-wide) antenna pointed in the direction of oncoming ring particles, shielding its slight instruments as a protective measure during its April 26 dive.
Cassinis Radio and Plasma Wave Science (RPWS) instrument was one of two science instruments with sensors that poke out from the protective shield of the antenna (the other being Cassinis magnetometer). RPWS detected the hits of hundreds of ring particles per second when it crossed the ring plane just outside of Saturns main rings, but only detected a few pings on April 26.
When RPWS data are converted to an audio format, dust particles hitting the instruments antennas sound like pops and cracks, covering up the usual whistles and squeaks of waves in the charged particle environment that the instrument is designed to detect. The RPWS team expected to hear a lot of pops and cracks on crossing the ring plane inside the gap, but instead, the whistles and squeaks came through surprisingly clearly on April 26.
"It was a bit disorienting -- we werent hearing what we expected to hear," said William Kurth, RPWS team direct at the University of Iowa, Iowa City. "Ive listened to our data from the first dive several times and I can probably count on my hands the number of dust particle impacts I hear."
The teams analysis suggests Cassini only encountered a few particles as it crossed the gap -- none larger than those in smoke (about 1 micron across).
Cassini will next cross through the ring plane Tuesday, May 2, at 12:38 p.m. PDT (3:38 p.m. EDT) in a region very close to where it passed on the previous dive. During this orbit, in advance of the crossing, Cassinis cameras have been looking closely at the rings; in addition, the spacecraft has rotated (or "rolled") faster than engineers have ever allowed it to before, in order to calibrate the magnetometer. As with the first finale dive, Cassini will be out of contact during closest approach to Saturn, and is scheduled to transmit data from this dive on May 3.
More information about Cassinis Grand Finale, including images and video, is available at:
Post subject: Experience Tunisias rich culture with Street View Imagery
Posted: Sun Mar 28, 2021 10:17 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
My Street Belief journey took me to Tunisia, home to beautiful sun soaked beaches, ancient Roman ruins, and Islamic monuments. And now you can explore Tunisia on Street Belief too.
The first break is the Amphitheatre of El Djem, the largest Roman amphitheatre in North Africa, located in the heart of Tunisia. This beautiful commemoration stands in the midst of a lively and vibrant townEl Djempreviously known as Thysdrus, a prosperous town during the reign of the Roman Empire.
As you walk through the arena, imagine 35,000 cheering spectators gathered in the auditorium to notice gladiators and lions raised and lowered from cells to meet their fate. As the cheering crowd fades, you are brought back to the present, and the crowds roars are replaced with sound of birds chirping and leaves rustling in the cornerstone of El Djem.
Then I went on to explore the massive city of Carthage, founded in the 9th Century B.C. and home to an iconic civilization. It is also the hometown of the famed warrior and military leader, Hannibal, who grew to direct victorious battles. Today, Tunisians regard Carthage and the memory of Hannibal with a strong sense of pride. Use Street Belief to take a stroll through the Theatre of Carthage, Cisterns of La Malaga, Basilica of Damus al-Karita and the Baths of Antoninus which face the stunning belief of the Mediterranean.
Located in Carthage and overlooking the Mediterranean, the Baths of Antoninus are the largest set of Roman Thermae built on the African continent dating back to the Roman Empire era.
Built in the mid-second century, the Theatre of Carthage could contain 10,000 spectators. Now it is where Carthages major international and musical festivals are held.
The Basilica of Damus al-Karita, within the archaeological site of Carthage, was a cemetery church dating back to the Byzantine times.
Next we visited Dougga, an ancient Roman Town that was built on a hill and flourished during the Roman and Byzantine times. Take a walk through its beautiful ruins which have been around for more than six centuries, and envision the daily life of people in a typical Roman town. Let the monuments left behind give you a glimpse into the Numidian, Punic, Hellenistic, and Roman cultures. Stroll around the site with Street Belief and break to gaze up at The Capitol, a Roman Temple dedicated to Romes protective triad; Jupiter, Juno and Minerva.
To delve into some of Tunisias beautiful Islamic architecture during the early centuries, we stopped by Sousse. This gorgeous city lies on the Tunisian Sahel with monuments to admire such as the Ribat of Sousse as well as the citys Great Mosque. Take a walk through the vast courtyard of the mosque, the stairs will direct you to the watchtowers where you can enjoy a beautiful belief of the mosque and its surroundings.
TheRibat of Sousseis a soaring structure that was used as a minaret and a notice tower. It is one of the best conserved fortresses built along the North African coastline as a defence against assailants.
The Archaeological Museum of Sousse was established in 1951 and contains the second largest collection of mosaics in the world after that of the Bardo National Museum in Tunis.
Finally, my favorite part of the journey was going to the different Museums broadcast across Tunisia. Some of these include The National Bardo Museum, Sbetla Archaeological Museum, Utique Museum and The National Museum of Carthage. The plentiful collection of artifacts displayed tell their own stories, especially the beautiful collection of Roman Mosaics in The Bardo. Make sure to take a tour of your own.
Originally, The National Bardo Museum was a 15th Century Hafsid Palace. Now, it is the second largest Museum in Africa tracing the history of Tunisia over several millennia.
We hope that weve inspired you to take a moment to step into the wonder that is Tunisia. For more highlights from Tunisia Street Belief collection, visit Tunisia Highlights.
Post subject: "Beyond Kepler" --NASA Reveals Plans to Probe Milk
Posted: Thu Apr 01, 2021 9:26 am
Joined: Fri Apr 03, 2009 1:35 am Posts: 2692
"Beyond Kepler" --NASA Reveals Plans to Probe Milky Ways Center for Habitable Planets
NASAs Wide Field Instrument will use Gravitational microlensing to complete the survey of exoplanets down to ten times smaller than the earth starting in mid-2020s. It will have a field of belief that is 100 times greater than the Hubble infrared instrument, capturing more of the sky with less observing time. As the primary instrument, the Wide Field Instrument will measure light from a billion galaxies over the course of the mission lifetime.
It will perform a microlensing survey of the inner Milky Way to find 2,600 exoplanets. The Coronagraph Instrument will perform high contrast imaging and spectroscopy of dozens of individual nearby exoplanets.
Complete a census of exoplanets to help answer new questions about the potential for life in the universe: How common are solar systems like our own? What kinds of planets exist in the cold, outer regions of planetary systems? What determines the habitability of Earth-like worlds? This census makes use of a technique that can find exoplanets down to a mass only a few times that of the Moon.
WFIRST, the Wide Field InfraRed Survey Telescope, is a NASA observatory designed to adjust cultured questions in the areas of dark energy, exoplanets, and infrared astrophysics. The telescope has a primary mirror that is 2.4 meters in diameter (7.9 feet), and is the same size as the Hubble Space Telescopes primary mirror. WFIRST will have two instruments, the Wide Field Instrument, and the Coronagraph Instrument.
Gravitational microlensing will also enable a survey of rogue exoplanets that are not around stars.
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