Monstrous-mind - The Monster Mind

What’s Up For September 2018?

Outstanding views Venus, Jupiter, Saturn and Mars with the naked eye!

You’ll have to look quickly after sunset to catch Venus. And through binoculars or a telescope, you’ll see Venus’s phase change dramatically during September - from nearly half phase to a larger thinner crescent!

Jupiter, Saturn and Mars continue their brilliant appearances this month. Look southwest after sunset.

Use the summer constellations help you trace the Milky Way.

Sagittarius: where stars and some brighter clumps appear as steam from the teapot.

Aquila: where the Eagle’s bright Star Altair, combined with Cygnus’s Deneb, and Lyra’s Vega mark the Summer Triangle. 

Cassiopeia, the familiar “w”- shaped constellation completes the constellation trail through the Summer Milky Way. Binoculars will reveal double stars, clusters and nebulae. 

Between September 12th and the 20th, watch the Moon pass from near Venus, above Jupiter, to the left of Saturn and finally above Mars! 

Both Neptune and brighter Uranus can be spotted with some help from a telescope this month.

Look at about 1:00 a.m. local time or later in the southeastern sky. You can find Mercury just above Earth’s eastern horizon shortly before sunrise. Use the Moon as your guide on September 7 and 8th.

And although there are no major meteor showers in September, cometary dust appears in another late summer sight, the morning Zodiacal light. Try looking for it in the east on moonless mornings very close to sunrise. To learn more about the Zodiacal light, watch “What’s Up” from March 2018.

Watch the full What’s Up for September 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

String Theory

String theory is a fascinating physical model in which all particles are replaced by one-dimensional objects known as strings. This theory says that we live in more than four dimensions, but we can not perceive them.

String theory, is a complete theory and unites quantum physics with Einstein’s general relativity.

On distance scales larger than the string scale, a string looks just like an ordinary particle, with its mass, charge, and other properties determined by the vibrational state of the string. In string theory, one of the many vibrational states of the string corresponds to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity.

According to string theory, the reason we can not observe these dimensions is because they are very small and compact (smaller than the plank length 10 −35)

Compactification is one way of modifying the number of dimensions in a physical theory. In compactification, some of the extra dimensions are assumed to “close up” on themselves to form circles. In the limit where these curled up dimensions become very small, one obtains a theory in which spacetime has effectively a lower number of dimensions. A standard analogy for this is to consider a multidimensional object such as a garden hose. If the hose is viewed from a sufficient distance, it appears to have only one dimension, its length. However, as one approaches the hose, one discovers that it contains a second dimension, its circumference. Thus, an ant crawling on the surface of the hose would move in two dimensions.

Compactification can be used to construct models in which spacetime is effectively four-dimensional. However, not every way of compactifying the extra dimensions produces a model with the right properties to describe nature. In a viable model of particle physics, the compact extra dimensions must be shaped like a Calabi–Yau manifold

Another approach to reducing the number of dimensions is the so-called brane-world scenario. In this approach, physicists assume that the observable universe is a four-dimensional subspace of a higher dimensional space. In such models, the force-carrying bosons of particle physics arise from open strings with endpoints attached to the four-dimensional subspace, while gravity arises from closed strings propagating through the larger ambient space. This idea plays an important role in attempts to develop models of real world physics based on string theory, and it provides a natural explanation for the weakness of gravity compared to the other fundamental forces

One notable feature of string theories is that these theories require extra dimensions of spacetime for their mathematical consistency. In bosonic string theory, spacetime is 26-dimensional, while in superstring theory it is 10-dimensional, and in M-theory it is 11-dimensional. In order to describe real physical phenomena using string theory, one must therefore imagine scenarios in which these extra dimensions would not be observed in experiments.

The original version of string theory was bosonic string theory, but this version described only bosons, a class of particles which transmit forces between the matter particles, or fermions. Bosonic string theory was eventually superseded by theories called superstring theories. These theories describe both bosons and fermions, and they incorporate a theoretical idea called supersymmetry.

This is a mathematical relation that exists in certain physical theories between the bosons and fermions. In theories with supersymmetry, each boson has a counterpart which is a fermion, and vice versa.

There are several versions of superstring theory: type I, type IIA, type IIB, and two flavors of heterotic string theory (SO(32) and E8×E8). The different theories allow different types of strings, and the particles that arise at low energies exhibit different symmetries. For example, the type I theory includes both open strings (which are segments with endpoints) and closed strings (which form closed loops), while types IIA, IIB and heterotic include only closed strings.

Branes

In string theory and other related theories, a brane is a physical object that generalizes the notion of a point particle to higher dimensions. For instance, a point particle can be viewed as a brane of dimension zero, while a string can be viewed as a brane of dimension one. It is also possible to consider higher-dimensional branes. In dimension p, these are called p-branes. The word brane comes from the word “membrane” which refers to a two-dimensional brane

In string theory, D-branes are an important class of branes that arise when one considers open strings

D-branes are typically classified by their spatial dimension, which is indicated by a number written after the D. A D0-brane is a single point, a D1-brane is a line (sometimes called a “D-string”), a D2-brane is a plane, and a D25-brane fills the highest-dimensional space considered in bosonic string theory. There are also instantonic D(–1)-branes, which are localized in both space and time.

Duality

A striking fact about string theory is that the different versions of the theory prove to be highly non-trivial in relation. One of the relationships that exist between different theories is called S-duality. This is a relationship that says that a collection of interacting particles in a theory may in some cases be viewed as a collection of weak interacting particles in a completely different theory. Approximately, a collection of particles is said to interact strongly if they combine and deteriorate frequently and interact poorly if they do so infrequently. The type I string theory turns out to be equivalent by S-duality to the heterotic string theory SO (32). Likewise, type IIB string theory is related to itself in a non-trivial way by S-duality

Another relationship between different string theories is T-duality. Here one considers strings propagating around a circular extra dimension. T-duality states that a string propagating around a circle of radius R is equivalent to a string propagating around a circle of radius 1/R in the sense that all observable quantities in one description are identified with quantities in the dual description. For example, a string has momentum as it propagates around a circle, and it can also wind around the circle one or more times. The number of times the string winds around a circle is called the winding number. If a string has momentum p and winding number n in one description, it will have momentum n and winding number p in the dual description. For example, type IIA string theory is equivalent to type IIB string theory via T-duality, and the two versions of heterotic string theory are also related by T-duality.

Black holes

In general relativity, a black hole is defined as a region of spacetime in which the gravitational field is so strong that no particle or radiation can escape. In the currently accepted models of stellar evolution, black holes are thought to arise when massive stars undergo gravitational collapse, and many galaxies are thought to contain supermassive black holes at their centers. 

Black holes are also important for theoretical reasons, as they present profound challenges for theorists attempting to understand the quantum aspects of gravity. String theory has proved to be an important tool for investigating the theoretical properties of black holes because it provides a framework in which theorists can study their thermodynamics.

The big bang theory doesn’t offer any explanation for what started the original expansion of the universe. This is a major theoretical question for cosmologists, and many are applying the concepts of string theory in attempts to answer it. One controversial conjecture is a cyclic universe model called the ekpyrotic universe theory, which suggests that our own universe is the result of branes colliding with each other.

Some things that string theory could explain: Neutrinos would have to have mass (minimum), Decay of Proton, New fields of force (short and long range) defined by some forms of calabi-yau, Explanations for Dark Matter.

sources: x, x, x, x, x, x

String theory is a very complex and broad area, so this post is only a summary. To better understand, I suggest you read Brian Greene’s books: The Elegant Universe and The Fabric of the Cosmo.

🔭🌌🪐

Saturn - March 11 2006

Image Credit: NASA/JPL-Caltech/CCI/CICLOPS/Kevin M. Gill

Everything You Need to Know About the Aug. 21 Eclipse

On Aug. 21, all of North America will experience a solar eclipse.

If skies are clear, eclipse-watchers will be able to see a partial solar eclipse over several hours, and some people – within the narrow path of totality – will see a total solar eclipse for a few moments.

How to Watch

It’s never safe to look at the Sun, and an eclipse is no exception. During a partial eclipse (or on any regular day) you must use special solar filters or an indirect viewing method to watch the Sun.

If you have solar viewing glasses, check to make sure they’re safe and undamaged before using them to look at the Sun. Make sure you put them on before looking up at the Sun, and look away before removing them. Eclipse glasses can be used over your regular eyeglasses, but they should never be used when looking through telescopes, binoculars, camera viewfinders, or any other optical device.

If you don’t have eclipse glasses, you can still watch the eclipse indirectly! You can make a pinhole projector out of a box, or use any other object with tiny holes – like a piece of cardstock with a hole, or your outstretched, interlaced fingers – to project an image of the partially eclipsed Sun onto the ground.

Of course, if it’s cloudy (or you’d just rather stay inside), you can watch the whole thing online with us at nasa.gov/eclipselive. Tune in starting at noon ET.

If you’re in the path of totality, there will be a few brief moments when it is safe to look directly at the eclipse. Only once the Moon has completely covered the Sun and there is no light shining through is it safe to look at the eclipse. Make sure you put your eclipse glasses back on or return to indirect viewing before the first flash of sunlight appears around the Moon’s edge.

Why do eclipses happen?

A solar eclipse happens when the Moon passes directly between the Sun and Earth, casting its shadow down on Earth’s surface. The path of totality – where the Moon completely covers the Sun – is traced out by the Moon’s inner shadow, the umbra. People within the Moon’s outer shadow, the penumbra, can see a partial eclipse.

The Moon’s orbit around Earth is tilted by about five degrees, meaning that its shadow usually doesn’t fall on Earth. Only when the Moon lines up exactly between the Sun and Earth do we see an eclipse.

Though the Sun is about 400 times wider than the Moon, it is also about 400 times farther away, making their apparent sizes match up almost exactly. This is what allows the Moon to block out the Sun’s bright face, while revealing the comparatively faint, pearly-white corona.

The Science of Eclipses

Eclipses are a beautiful sight to see, and they’re also helpful for our scientists, so we’re funding eleven ground-based science investigations to learn more about the Sun and Earth.

Total solar eclipses reveal the innermost regions of the Sun’s atmosphere, the corona. Though it’s thought to house the processes that kick-start much of the space weather that can influence Earth, as well as heating the whole corona to extraordinarily high temperatures, we can’t study this region at any other time. This is because coronagraphs – the instruments we use to study the Sun’s atmosphere by creating artificial eclipses – must cover up much of the corona, as well as the Sun’s face in order to produce clear images.

Eclipses also give us the chance to study Earth’s atmosphere under uncommon conditions: the sudden loss of solar radiation from within the Moon’s shadow. We’ll be studying the responses of both Earth’s ionosphere – the region of charged particles in the upper atmosphere – and the lower atmosphere.

Learn all about the Aug. 21 eclipse at eclipse2017.nasa.gov, and follow @NASASun on Twitter and NASA Sun Science on Facebook for more. Watch the eclipse through the eyes of NASA at nasa.gov/eclipselive starting at 12 PM ET on Aug. 21. 

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

Asperitas and Mammatus

Well-defined, wave-like structures in the underside of the cloud; more chaotic and with less horizontal organization than the variety undulatus. Asperitas is characterized by localized waves in the cloud base, either smooth or dappled with smaller features, sometimes descending into sharp points, as if viewing a roughened sea surface from below. Varying levels of illumination and thickness of the cloud can lead to dramatic visual effects.

Occurs mostly with Stratocumulus and Altocumulus

Mammatus is a cellular pattern of pouches hanging underneath the base of a cloud, typically cumulonimbus rainclouds, although they may be attached to other classes of parent clouds.

source | source | images: x, x, x, x, x, x, x

🔭🌃🌌

Celestial Fireworks: Into Star Cluster Westerlund 2

What if you could go directly to a cluster where the stars are forming? This animation was done with 3D computer modeling of the region around the star cluster Westerlund 2, based on Hubble Space Telescope images in visible and infrared light. Westerlund 2 covers about 10 light-years and is about 20 thousand light years distant towards the constellation Keel of the ship (Carina). As the illustrative animation begins, the larger Gum 29 nebula fills the screen with the young group of bright stars visible in the center. Stars pass your finger as you approach the cluster. Soon, your imaginary vessel rotates and you pass over the interstellar gas and dust pillars during the light year. Strong winds and radiations from young, massive stars destroy all but the densest clumps of dust, leaving these pillars in their shadows - many pointing back to the center of the cluster. Lastly, you move to the top of the set of stars and search hundreds of the most gigantic stars known.

Credit: NASA, ESA, Hubble, J. Anderson et al. (STScI); Acknowledgment: The Hubble Heritage Team (STScI/AURA), A. Nota (ESA/STScI), the Westerlund 2 Science Team, and the ES

Pleiades by Chuck Manges

🛫🔭🌌

10 Amazing Space Discoveries by the World’s Largest Flying Observatory

On the night of May 26, 2010, the Stratospheric Observatory for Infrared Astronomy, or SOFIA, the world’s largest flying observatory, first peered into the cosmos. Its mission: to study celestial objects and astronomical phenomena with infrared light. Many objects in space emit almost all their energy at infrared wavelengths. Often, they are invisible when observed in ordinary, visible light. Over the last decade, the aircraft’s 106-inch telescope has been used to study black holes, planets, galaxies, star-forming nebulas and more! The observations have led to major breakthroughs in astronomy, revolutionizing our understanding of the solar system and beyond. To celebrate its 10 years of exploration, here’s a look at the top 10 discoveries made by our telescope on a plane:

The Universe’s First Type of Molecule

Scientists believe that around 100,000 years after the big bang, helium and hydrogen combined to make a molecule called helium hydride. Its recent discovery confirms a key part of our basic understanding of the early universe.

A New View of the Milky Way

More than a pretty picture, this panorama of cosmic scale reveals details that can help explain how massive stars are born and what’s feeding our Milky Way galaxy’s supermassive black hole.

When Planets Collide

A double-star system that is more than 300 light-years away likely had an extreme collision between two of its rocky planets. A similar event in our own solar system may have formed our Moon.

How A Black Hole Feasts

Fear not, the dark, my friend. And let the feast begin! Magnetic fields in the Cygnus A galaxy are trapping material where it is close enough to be devoured by a hungry black hole.

Somewhere Like Home

The planetary system around Epsilon Eridani, a star located about 10 light-years away, has an architecture remarkably similar to our solar system. What’s more, its central star is a younger, fainter version of our Sun.

A Quiet Place

Black holes in many galaxies are actively consuming material, but our Milky Way galaxy’s central black hole is relatively quiet. Observations show magnetic fields may be directing material around, not into, the belly of the beast.

The Great Escape

Ever wonder how material leaves a galaxy? The wind flowing from the center of the Cigar Galaxy is so strong it’s pulling a magnetic field — and the mass of 50 to 60 million Suns — with it.

Exploding Star, New Worlds

What happens when a star goes boom? It turns out that supernova explosions can produce a substantial amount of material from which planets like Earth can form.

Stellar Sibling Rivalry

They say siblings need time and space to grow, but here’s one that really needs some room. A newborn star in the Orion Nebula is clearing a bubble of space around it, preventing any new luminous family members from forming nearby.

Clues to Life’s Building Blocks

Radiation from stars is making organic molecules in nebula NGC 7023, also known as the Iris Nebula, larger and more complex. The growth of these molecules is one of the steps that could lead to the emergence of life under the right circumstances.

SOFIA is a modified Boeing 747SP aircraft that allows astronomers to study the solar system and beyond in ways that are not possible with ground-based telescopes. Find out more about the mission at www.nasa.gov/SOFIA.

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

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

NASA’s TESS Mission Hopes to Find Exoplanets Beyond Our Solar System : The worlds orbiting other stars are called “exoplanets,” and they come in a wide variety of sizes, from gas giants larger than Jupiter to small, rocky planets about as big around as Earth or Mars. This rocky super-Earth is an illustration of the type of planets future telescopes, like NASA’s TESS, hope to find outside our solar system. (via NASA)