light phenomenon

10 cool rocks you probably didn’t know about

1) lepidolite

lepidolite is a variety of mica and is typically pink or lavender colored. when tumbled it is extremely glittery – pictures don’t do it justice!

2) ulexite

ulexite is also called “tv rock” and has a super unique optical effect – when placed over something it displays that image onto the top of the rock. it’s not merely opaque – the fibers within the mineral literally project an image onto the surface of the stone.

3) pietersite

pietersite has chatoyancy – much like tiger’s eye – that creates movement and shine through the surface of the stone. however, unlike tiger’s eye, pietersite’s chatoyancy is in swirls instead of straight lines. it’s incredible to behold – i recommend looking up pietersite on youtube and checking out videos of it under good lighting.

4) optical calcite/iceland spar

this type of calcite is actually completely clear, but refracts the light going through it in ways that create rainbows and other neat optical effects. isaac newton himself actually studied this rock to help better understand the nature of light itself & the phenomenon of optical illusions.

5) alexandrite

alexandrite is a variety of chrysoberyl that exhibits a color change! it changes from a greenish hue to a brilliant red depending on the type of light and the source. the color changes in alexandrite are phenomenal and rarely seen in other stones.

6) spectrolite

don’t let the image fool you – this stone is actually pure black. the brilliant colors it exhibits are just a flash (it’s actually called labradorescence, which is what the stone labradorite is named for). spectrolite is an uncommon form of labradorite mined only from finland. some varieties of high quality labradorite from madagascar can show a spectrolite play, but nothing is as dark with as brilliant a flash as spectrolite.

7) specular hematite

specular hematite is a variety of hematite that has a beautiful, glimmering surface especially when polished. much like lepidolite, the shimmer of specular hematite is caused by mica.

8) boulder opal

boulder opal is ironstone with cracks of brilliant natural opal running through it. these formations are entirely natural. opal has the most brilliant and vibrantly colored flash of any other stone.

9) enhydro quartz

enhydro quartz is a variety of quartz that was formed with naturally occuring water & air bubbles within them! in some specimens the water bubbles will actually move underneath the surface of the crystal.

10) fire agate

fire agate is actually a form of chalcedony, and is well known for having a beautiful rainbow effect caused by schiller, rather than flash or labradorescence. 

What’s Up for February?

What’s Up for February? Look to the night sky for a brighter Venus, Comet 45P, asteroid Vesta and more. 

Tonight, you can see Venus along with a crescent moon, Mars and Uranus just after sunset. No binoculars needed! 

While there are no meteor showers this month, behold the zodiacal light!

This phenomenon is caused when sunlight reflects off dust particles in the plane of our solar system. Use Venus and Mars as a cone-shaped guide on the western horizon in late February and March.

Comet 45P will be visible using binoculars and telescope and will make its closest approach to Earth on February 11.

Finally, bright asteroid Vesta can be found in the constellation Pisces.

Follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Hubble Sees A Smiling Lens: In the center of this image, taken with the NASA/ESA Hubble Space Telescope, is the galaxy cluster SDSS J1038+4849 and it seems to be smiling.

You can make out its two orange eyes and white button nose. In the case of this happy face, the two eyes are very bright galaxies and the misleading smile lines are actually arcs caused by an effect known as strong gravitational lensing.

Galaxy clusters are the most massive structures in the Universe and exert such a powerful gravitational pull that they warp the spacetime around them and act as cosmic lenses which can magnify, distort and bend the light behind them. This phenomenon, crucial to many of Hubbles discoveries, can be explained by Einsteins theory of general relativity.

In this special case of gravitational lensing, a ring known as an Einstein Ring is produced from this bending of light, a consequence of the exact and symmetrical alignment of the source, lens and observer and resulting in the ring-like structure we see here.

Hubble has provided astronomers with the tools to probe these massive galaxies and model their lensing effects, allowing us to peer further into the early Universe than ever before. This object was studied by Hubbles Wide Field and Planetary Camera 2 as part of a survey of strong lenses.

A version of this image was entered into the Hubbles Hidden Treasures image processing competition by contestant Judy Schmidt.

Image Credit: NASA/ESA
Caption: ESA

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5 Questions You Were Too Embarrassed To Ask About The Expanding Universe

5.) Are there galaxies moving away faster than the speed of light, and isn’t that forbidden? From our point of view, the space in between us and any distant point is expanding. The farther away something is, the faster it appears to recede from us. Even if the expansion rate were tiny, an object far enough away would eventually cross that threshold of any finite speed, since an expansion rate (a speed-per-distance) multiplied by a great enough distance will give you a speed as fast as you want. But this is okay in General Relativity! The law that nothing can travel faster than the speed of light only applies to an object’s motion through space, not to the expansion of space itself. In reality, the galaxies themselves only move around at speeds that are hundreds or thousands of km/s, much lower than the 300,000 km/s speed limit set by the speed of light. It’s the expansion of the Universe that causes this recession and the redshift, not a true galactic motion.”

The idea that the spatial fabric of the Universe itself is expanding, and that’s what’s behind the observed relationship between redshift and distance has long been controversial, and also long-misunderstood. After all, if more distant objects appear to recede more quickly, couldn’t there be a different explanation, like an explosion that flung many things outward? As it turns out, this isn’t a mere difference in interpretation, there are observations we can make that tell us the answer! The Universe is not expanding ‘into’ anything, despite what your intuition might tell you. The Hubble ‘constant’ isn’t actually a constant, but is rather decreasing as time goes on. The Universe looks like it’s going to expand forever, but even that scientific conclusion is subject to revision depending on what data shows in the future. And although 97% of the galaxies in the Universe are already unreachable, it isn’t a violation of relativity or a faster-than-light phenomenon that’s to blame.

Come learn the answers to five questions about the expanding Universe that many are too embarrassed to ask!

SLI phenomenon

INTJ: Come here, look! This blue light really makes these leaves look pretty.

INTP: *walks over to stand under the street light* What do you mean, this light looks gre-

INTJ: Is it just me or is the light…

INTP: …gradually getting warmer?

Street light: *shuts off*

INTP: *instinctively grabs INTJ’s hand* fffUCK!

INTJ: FUCK. THIS. *quickly walks off, dragging INTP along*

His eyes are blue, and blue eyes up close are a celestial phenomenon: nebulae as seen through telescopes, the light of unnamed stars diffused through dusts and elements and endlessness. Layers of light. Blue eyes are starlight.
—  Laini Taylor, Night of Cake & Puppets
Nearly Half of Americans Believe in Aliens, According to New Survey

Nearly half of Americans believe in aliens, and nearly as many think aliens are visiting Earth, according to a new survey. Fewer than 20% believe in alien abduction, and even fewer claim that they have seen a UFO.

20th Century Fox Home Entertainment commissioned the survey as part of its promotional campaign for the Blu-ray release of the movie “Phoenix Forgotten.” The film is a sci-fi thriller set during the mass UFO sighting in Phoenix in 1997 that is referred to as “The Phoenix Lights.” The film was produced by Ridley Scott, whose producer and director credits include “Alien” and “The Martian.”

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“The Phoenix Lights phenomenon of March 13, 1997, led us to introduce a survey to find out what Americans believe about aliens,” a representative from 20th Century Fox Home Entertainment told OpenMinds.tv. “From our survey, we found that nearly half (47%) believe in aliens but less than a fifth think they’ve ever seen a UFO or alien themselves.”

More than 1,700 Americans took part in the survey that was conducted by communications and public relations firm Cohn and Wolfe.

Among the interesting findings in the survey was that about 39% “believe aliens have visited Earth before.” Only 18% believed in alien abduction.

Regarding UFOs, only 16.74% of those surveyed claimed to have seen one.

24/7 Wall St. posted a story in May on the states with the most UFO sightings, based on sightings per 100,000 in population.

To determine the states with the most UFO sightings, 24/7 Wall St. reviewed 2001 to 2015 sightings in data from Cheryl Costa’s “UFO Sightings Desk Reference: United States of America 2001-2015: Unidentified Flying Objects Frequency–Distribution–Shapes.”

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Vermont had the most, with 80.7 sightings per 100,000 people. The five states with the most sightings per 100,000 people are in either the Pacific Northwest or New England, areas associated with thick forests and that are sparsely populated. Mississippi had the fewest, with 21.3 sightings per 100,000 people.

As for Arizona, the state was sixth on the list, with 68.2 sightings per 100,000 people.

Other recent polls have found most people believe intelligent life exists beyond Earth. Most Americans, British and Germans think that intelligent alien life exists. That poll, conducted by the market-research company YouGov two years ago, found the Germans are most likely to believe, at 56%, followed by Americans and British, at 54% and 52%, respectively.

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