Latest Posts by monstrous-mind - Page 7

What is a Wormhole?

Wormholes were first theorized in 1916, though that wasn’t what they were called at the time. While reviewing another physicist’s solution to the equations in Albert Einstein’s theory of general relativity, Austrian physicist Ludwig Flamm realized another solution was possible. He described a “white hole,” a theoretical time reversal of a black hole. Entrances to both black and white holes could be connected by a space-time conduit.

In 1935, Einstein and physicist Nathan Rosen used the theory of general relativity to elaborate on the idea, proposing the existence of “bridges” through space-time. These bridges connect two different points in space-time, theoretically creating a shortcut that could reduce travel time and distance. The shortcuts came to be called Einstein-Rosen bridges, or wormholes.

Certain solutions of general relativity allow for the existence of wormholes where the mouth of each is a black hole. However, a naturally occurring black hole, formed by the collapse of a dying star, does not by itself create a wormhole.

Wormholes are consistent with the general theory of relativity, but whether wormholes actually exist remains to be seen.

A wormhole could connect extremely long distances such as a billion light years or more, short distances such as a few meters, different universes, or different points in time

For a simplified notion of a wormhole, space can be visualized as a two-dimensional (2D) surface. In this case, a wormhole would appear as a hole in that surface, lead into a 3D tube (the inside surface of a cylinder), then re-emerge at another location on the 2D surface with a hole similar to the entrance. An actual wormhole would be analogous to this, but with the spatial dimensions raised by one. For example, instead of circular holes on a 2D plane, the entry and exit points could be visualized as spheres in 3D space.

Science fiction is filled with tales of traveling through wormholes. But the reality of such travel is more complicated, and not just because we’ve yet to spot one.

The first problem is size. Primordial wormholes are predicted to exist on microscopic levels, about 10–33 centimeters. However, as the universe expands, it is possible that some may have been stretched to larger sizes.

Another problem comes from stability. The predicted Einstein-Rosen wormholes would be useless for travel because they collapse quickly.

“You would need some very exotic type of matter in order to stabilize a wormhole,” said Hsu, “and it’s not clear whether such matter exists in the universe.”

But more recent research found that a wormhole containing “exotic” matter could stay open and unchanging for longer periods of time.

Exotic matter, which should not be confused with dark matter or antimatter, contains negative energy density and a large negative pressure. Such matter has only been seen in the behavior of certain vacuum states as part of quantum field theory.

If a wormhole contained sufficient exotic matter, whether naturally occurring or artificially added, it could theoretically be used as a method of sending information or travelers through space. Unfortunately, human journeys through the space tunnels may be challenging.

Wormholes may not only connect two separate regions within the universe, they could also connect two different universes. Similarly, some scientists have conjectured that if one mouth of a wormhole is moved in a specific manner, it could allow for time travel.

Although adding exotic matter to a wormhole might stabilize it to the point that human passengers could travel safely through it, there is still the possibility that the addition of “regular” matter would be sufficient to destabilize the portal.

Today’s technology is insufficient to enlarge or stabilize wormholes, even if they could be found. However, scientists continue to explore the concept as a method of space travel with the hope that technology will eventually be able to utilize them.

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What’s Up For August 2018?

The summer Perseids are here! 

The Perseid meteor shower is the best of the year! It peaks on a Moonless summer night from 4 p.m. EST on August 12 until 4 a.m. EST on August 13.

Because the new Moon falls near the peak night, the days before and after the peak will also provide nice, dark skies. Your best window of observation is from a few hours after twilight until dawn, on the days surrounding the peak.

Unlike most meteor showers, which have a short peak of high meteor rates, the Perseids have a very broad peak, as Earth takes more than three weeks to plow through the wide trail of cometary dust from comet Swift-Tuttle.

The Perseids appear to radiate from the constellation Perseus, visible in the northern sky soon after sunset this time of year. Observers in mid-northern latitudes will have the best views.

You should be able to see some meteors from July 17 to August 24, with the rates increasing during the weeks before August 12 and decreasing after August 13.

Observers should be able to see between 60 and 70 per hour at the peak. Remember, you don’t have to look directly at the constellation to see them. You can look anywhere you want to-even directly overhead.

Meteor showers like the Perseids are caused by streams of meteoroids hitting Earth’s atmosphere. The particles were once part of their parent comet-or, in some cases, from an asteroid.

The parade of planets Venus, Jupiter, Saturn and Mars–and the Milky Way continue to grace the evening sky, keeping you and the mosquitoes company while you hunt for meteors.

Watch the full What’s Up for August Video: 

There are so many sights to see in the sky. To stay informed, subscribe to our What’s Up video series on Facebook.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Why Won’t Our Parker Solar Probe Melt?

This summer, our Parker Solar Probe will launch to travel closer to the Sun than any mission before it, right into the Sun’s outer atmosphere, the corona.

The environment in the corona is unimaginably hot: The spacecraft will travel through material with temperatures greater than 3 million degrees Fahrenheit. 

So…why won’t it melt? 

The Difference Between Heat and Temperature

Parker Solar Probe was designed from the ground up to keep its instruments safe and cool, but the nature of the corona itself also helps. The key lies in the difference between heat and temperature.

Temperature measures how fast particles are moving, while heat is the total amount of energy that they transfer. The corona is an incredibly thin and tenuous part of the Sun, and there are very few particles there to transfer energy – so while the particles are moving fast (high temperature), they don’t actually transfer much energy to the spacecraft (low heat).

It’s like the difference between putting your hand in a hot oven versus putting it in a pot of boiling water (don’t try this at home!). In the air of the oven, your hand doesn’t get nearly as hot as it would in the much denser water of the boiling pot. 

So even though Parker Solar Probe travels through a region with temperatures of several million degrees, the surface of its heat shield will reach only about 2,500 F.

The Heat Shield

Of course, thousands of degrees Fahrenheit is still way too hot for scientific instruments. (For comparison, lava from volcano eruptions can be anywhere between 1,300 to 2,200 F.) 

To withstand that heat, Parker Solar Probe is outfitted with a cutting-edge heat shield, called the Thermal Protection System. This heat shield is made of a carbon composite foam sandwiched between two carbon plates. The Sun-facing side is covered with a specially-developed white ceramic coating, applied as a plasma spray, to reflect as much heat as possible.

The heat shield is so good at its job that even though the Sun-facing side of the shield will be at 2,500 F, the instruments in its shadow will remain at a balmy 85 F.

Parker Solar Probe Keeps its Cool

Several other designs on the spacecraft help Parker Solar Probe beat the heat. 

Parker Solar Probe is not only studying the Sun – it’s also powered by it. But even though most of the surface area of its solar arrays can be retracted behind the heat shield, even that small exposed segment would quickly make them overheat while at the Sun.  

To keep things cool, Parker Solar Probe circulates a single gallon of water through its solar arrays. The water absorbs heat as it passes behind the arrays, then radiates that heat out into space as it flows into the spacecraft’s radiator. 

It’s also important for Parker Solar Probe to be able to think on its feet, since it takes about eight minutes for information to travel between Earth and the Sun. If we had to control the spacecraft from Earth, by the time we knew something went wrong, it would be too late to fix it. 

So Parker Solar Probe is smart: Along the edges of the heat shield’s shadow are seven sensors. If any of these sensors detect sunlight, they alert the central computer and the spacecraft can correct its position to keep the sensors – and the rest of the instruments – safely protected behind the heat shield.

Over the course of its seven-year mission, Parker Solar Probe will make 24 orbits of our star. On each close approach to the Sun, it will sample the solar wind, study the Sun’s corona, and provide unprecedentedly close up observations from around our star – and armed with its slew of innovative technologies, we know it will keep its cool the whole time. 

Parker Solar Probe launches summer 2018 on its mission to study the Sun. Keep up with the latest on the mission at nasa.gov/solarprobe or follow us on Twitter and Facebook.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Back to the Autumn | Alex Kaßner

By cabinsinthewoods

The evil in the world comes almost always from ignorance, and goodwill can cause as much damage as ill-will if it is not enlightened. People are more often good than bad, though in fact that is not the question. But they are more or less ignorant and this is what one calls vice or virtue, the most appalling vice being the ignorance that thinks it knows everything and which consequently authorizes itself to kill. The murderer’s soul is blind, and there is no true goodness or fine love without the greatest possible degree of clear-sightedness.

The Plague / Albert Camus

End of the line 🍁✨

Autumn Path by AnthonyPresley

The NASA/ESA Hubble Space Telescope captures the iridescent tapestry of star birth in a neighbouring galaxy in this panoramic view of glowing gas, dark dust clouds, and young, hot stars.

Credit: NASA/ESA and the Hubble Heritage Team (AURA/STScI/HEIC)

blue eyes or brown eyes?? or somewhere in between??

The Milky Way’s long-lost sibling finally found

Scientists at the University of Michigan have deduced that the Andromeda galaxy, our closest large galactic neighbor, shredded and cannibalized a massive galaxy two billion years ago.

Even though it was mostly shredded, this massive galaxy left behind a rich trail of evidence: an almost invisible halo of stars larger than the Andromeda galaxy itself, an elusive stream of stars and a separate enigmatic compact galaxy, M32. Discovering and studying this decimated galaxy will help astronomers understand how disk galaxies like the Milky Way evolve and survive large mergers.

This disrupted galaxy, named M32p, was the third-largest member of the Local Group of galaxies, after the Milky Way and Andromeda galaxies. Using computer models, Richard D'Souza and Eric Bell of the University of Michigan’s Department of Astronomy were able to piece together this evidence, revealing this long-lost sibling of the Milky Way. Their findings were published in Nature Astronomy.

source

Emily Thomas

Everyday IS Halloween🎃Even in a heatwave

The Moon, Venus and Mercury at Dawn 1 - Feb 7, 2016

image credit: Joseph Brimacombe

12 hours of exposure on the Whirlpool Galaxy revealing the faint dust hiding through out space

via reddit

🎃🎃🎃🎃🌄🍁🍂

🍁🍂

The Rift.

👏🍁🍂🌄🎃

Bliss…

Saturn Rings and Moons: From left, the moons are Janus, Pandora, Enceladus, Mimas and Rhea. Following the images below, Enceladus and Tethys, Titan, Rhea and Mimas. Enceladus and Tethys.

by Gordan Ugarkovic

10 Things: Calling All Pluto Lovers

June 22 marks the 40th anniversary of Charon’s discovery—the dwarf planet Pluto’s largest and first known moon. While the definition of a planet is the subject of vigorous scientific debate, this dwarf planet is a fascinating world to explore. Get to know Pluto’s beautiful, fascinating companion this week.

1. A Happy Accident

Astronomers James Christy and Robert Harrington weren’t even looking for satellites of Pluto when they discovered Charon in June 1978 at the U.S. Naval Observatory Flagstaff Station in Arizona – only about six miles from where Pluto was discovered at Lowell Observatory. Instead, they were trying to refine Pluto’s orbit around the Sun when sharp-eyed Christy noticed images of Pluto were strangely elongated; a blob seemed to move around Pluto. 

The direction of elongation cycled back and forth over 6.39 days―the same as Pluto’s rotation period. Searching through their archives of Pluto images taken years before, Christy then found more cases where Pluto appeared elongated. Additional images confirmed he had discovered the first known moon of Pluto.

2. Forever and Always

Christy proposed the name Charon after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto’s underworld. But Christy also chose it for a more personal reason: The first four letters matched the name of his wife, Charlene. (Cue the collective sigh.)

3. Big Little Moon

Charon—the largest of Pluto’s five moons and approximately the size of Texas—is almost half the size of Pluto itself. The little moon is so big that Pluto and Charon are sometimes referred to as a double dwarf planet system. The distance between them is 12,200 miles (19,640 kilometers).

4. A Colorful and Violent History

Many scientists on the New Horizons mission expected Charon to be a monotonous, crater-battered world; instead, they found a landscape covered with mountains, canyons, landslides, surface-color variations and more. High-resolution images of the Pluto-facing hemisphere of Charon, taken by New Horizons as the spacecraft sped through the Pluto system on July 14 and transmitted to Earth on Sept. 21, reveal details of a belt of fractures and canyons just north of the moon’s equator.

5. Grander Canyon

This great canyon system stretches more than 1,000 miles (1,600 kilometers) across the entire face of Charon and likely around onto Charon’s far side. Four times as long as the Grand Canyon, and twice as deep in places, these faults and canyons indicate a titanic geological upheaval in Charon’s past.

6. Officially Official

In April 2018, the International Astronomical Union—the internationally recognized authority for naming celestial bodies and their surface features—approved a dozen names for Charon’s features proposed by our New Horizons mission team. Many of the names focus on the literature and mythology of exploration.

7. Flying Over Charon

This flyover video of Charon was created thanks to images from our New Horizons spacecraft. The “flight” starts with the informally named Mordor (dark) region near Charon’s north pole. Then the camera moves south to a vast chasm, descending to just 40 miles (60 kilometers) above the surface to fly through the canyon system.

8. Strikingly Different Worlds

This composite of enhanced color images of Pluto (lower right) and Charon (upper left), was taken by New Horizons as it passed through the Pluto system on July 14, 2015. This image highlights the striking differences between Pluto and Charon. The color and brightness of both Pluto and Charon have been processed identically to allow direct comparison of their surface properties, and to highlight the similarity between Charon’s polar red terrain and Pluto’s equatorial red terrain.

9. Quality Facetime

Charon neither rises nor sets, but hovers over the same spot on Pluto’s surface, and the same side of Charon always faces Pluto―a phenomenon called mutual tidal locking.

10. Shine On, Charon

Bathed in “Plutoshine,” this image from New Horizons shows the night side of Charon against a star field lit by faint, reflected light from Pluto itself on July 15, 2015.

Read the full version of this week’s ‘10 Things to Know’ article on the web HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

High-resolution images of Pluto taken by NASA’s New Horizons spacecraft.

The plains on Pluto’s surface are composed of more than 98 percent nitrogen ice, with traces of methane and carbon monoxide. Nitrogen and carbon monoxide are most abundant on the anti-Charon face of Pluto (around 180° longitude, where Tombaugh Regio’s western lobe, Sputnik Planitia, is located), whereas methane is most abundant near 300° east. The mountains are made of water ice. Pluto’s surface is quite varied, with large differences in both brightness and color. Pluto is one of the most contrastive bodies in the Solar System, with as much contrast as Saturn’s moon Iapetus. The color varies from charcoal black, to dark orange and white. Pluto’s color is more similar to that of Io with slightly more orange and significantly less red than Mars. Notable geographical features include Tombaugh Regio, or the “Heart” (a large bright area on the side opposite Charon), Cthulhu Macula, or the “Whale” (a large dark area on the trailing hemisphere), and the “Brass Knuckles” (a series of equatorial dark areas on the leading hemisphere). Sputnik Planitia, the western lobe of the “Heart”, is a 1,000 km-wide basin of frozen nitrogen and carbon monoxide ices, divided into polygonal cells, which are interpreted as convection cells that carry floating blocks of water ice crust and sublimation pits towards their margins; there are obvious signs of glacial flows both into and out of the basin. It has no craters that were visible to New Horizons, indicating that its surface is less than 10 million years old.

source | images: NASA/JPL

Ten interesting facts about Jupiter

Here is a list of some interesting facts about the planet Jupiter. A planet that catches the attention of all, by its size, storms and its surprising moons.

The mass of Jupiter is 318 times as massive as the Earth. In fact, Jupiter is 2.5 times more massive than all of the other planets in the Solar System combined.

Its gravity is so strong that a rocket would have to go an unthinkable 135,000 mph to leave.

The Great Red Spot on Jupiter is one of its most familiar features. This persistent anticyclonic storm, which is located south of its equator, measures between 24,000 km in diameter and 12–14,000 km in height. As such, it is large enough to contain two or three planets the size of Earth’s diameter. And the spot has been around for at least 350 years, since it was spotted as far back as the 17th century.

Jupiter’s rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft that orbited Jupiter from 1995 to 2003 later confirmed that these rings were created by meteoroid impacts on small nearby moons.

Extending up to seven million kilometers in the Sun’s direction and almost to the orbit of Saturn in the opposite direction, Jupiter’s magnetosphere is the largest and most powerful of any planetary magnetosphere in the Solar System, and by volume the largest known continuous structure in the Solar System after the heliosphere.

Jupiter has a total of 69 natural satellites. The four largest are: Io, Europa, Ganymede and Callisto. However, it is estimated that the planet has over 200 natural satellites orbiting it. Almost all of them are less than 10 kilometers in diameter, and were only discovered after 1975, when the first spacecraft (Pioneer 10) arrived at Jupiter.

Jupiter Has Been Visited 8 Times By Spacecraft. Jupiter was first visited by NASA’s Pioneer 10 spacecraft in December 1973, and then Pioneer 11 in December 1974. Then came the Voyager 1 and 2 flybys, both of which happened in 1979. This was followed by a long break until Ulysses arrived in February 1992, followed by the Galileo space probe in 1995. Then Cassini made a flyby in 2000, on its way to Saturn. And finally, NASA’s New Horizons spacecraft made its flyby in 2007. NASA’s Juno spacecraft is currently orbiting Jupiter.

Jupiter is the third brightest object in the Solar System, after Venus and the Moon.

Jupiter Is The Fastest Spinning Planet In The Solar System. For all its size and mass, Jupiter sure moves quickly. In fact, with an rotational velocity of 12.6 km/s (~7.45 m/s) or 45,300 km/h (28,148 mph), the planet only takes about 10 hours to complete a full rotation on its axis. And because it’s spinning so rapidly, the planet has flattened out at the poles a little and is bulging at its equator.

Jupiter Cannot Become A Star. Astronomers call Jupiter a failed star, but that’s not really an appropriate description. While it is true that, like a star, Jupiter is rich in hydrogen and helium, Jupiter does not have nearly enough mass to trigger a fusion reaction in its core. This is how stars generate energy, by fusing hydrogen atoms together under extreme heat and pressure to create helium, releasing light and heat in the process.

This is made possible by their enormous gravity. For Jupiter to ignite a nuclear fusion process and become a star, it would need more than 70 times its current mass. If you could crash dozens of Jupiters together, you might have a chance to make a new star. But in the meantime, Jupiter shall remain a large gas giant with no hopes of becoming a star. Sorry, Jupiter!

Sources: universetoday and wikipedia

Images credits: Wikimedia Commons, JAXA, NASA, ESA, Hubble, Wang Letian & Michael Carroll

Planetary nebula

A planetary nebula, abbreviated as PN or plural PNe, is a kind of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The word “nebula” is Latin for mist or cloud, and the term “planetary nebula” is a misnomer that originated in the 1780s with astronomer William Herschel because, when viewed through his telescope, these objects resemble the rounded shapes of planets. Herschel’s name for these objects was popularly adopted and has not been changed. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years.

Most planetary nebulae form at the end of the star’s life, during the red giant phase, when the outer layers of the star are expelled by strong stellar winds. After most of the red giant’s atmosphere is dissipated, the ultraviolet radiation of the hot luminous core, called a planetary nebula nucleus (PNN), ionizes the ejected material. Absorbed ultraviolet light energises the shell of nebulous gas around the central star, causing it to appear as a brightly coloured planetary nebula.

Planetary nebulae likely play a crucial role in the chemical evolution of the Milky Way by expelling elements to the interstellar medium from stars where those elements were created. Planetary nebulae are observed in more distant galaxies, yielding useful information about their chemical abundances.

Stars greater than 8 solar masses (M⊙) will likely end their lives in dramatic supernovae explosions, while planetary nebulae seemingly only occur at the end of the lives of intermediate and low mass stars between 0.8 M⊙ to 8.0 M⊙.

source 

images: NASA/ESA, Hubble