If You Dropped A Water Balloon On A Bed Of Nails, You’d Expect It To Burst Spectacularly. And You’d

Living near the Rocky Mountains, it’s not unusual to look up and find the sky striped with lines of clouds. Such wave clouds are often formed on the lee side of mountains and other topography. But even in the flattest plains, you can find clouds like these at times. That’s because the internal waves necessary to create the clouds can be generated by weather fronts, too.

Imagine a bit of atmosphere sitting between a low-pressure zone and a high-pressure zone. This will be an area of convergence, where winds flow inward and squeeze the fluid parcel in one direction before turning 90 degrees and stretching it in the perpendicular direction. The result is a sharpening of any temperature gradient along the interface. This is the weather front that moves in and causes massive and sudden shifts in temperature. 

On one side of the front, warm air rises. Then, as it loses heat and cools, it sinks down the cold side of the front. The sharper the temperature differences become, the stronger this circulation gets. If the air is vertically displaced quickly enough, it will spontaneously generate waves in the atmosphere. With the right moisture conditions, those waves create visible clouds at their crests, as seen here. For more on the process, check out this article over at Physics Today. (Image credit: W. Velasquez; via Physics Today)

Solar System: 10 Things to Know

Movie Night

Summer break is just around the corner. Hang a sheet from the clothesline in the backyard and fire up the projector for a NASA movie night.

1. Mars in a Minute

Back in the day, movies started with a cartoon. Learn the secrets of the Red Planet in these animated 60 second chunks.

2. Crash of the Titans

Watch two galaxies collide billions of years from now in this high-definition visualization.

3. Tour the Moon in 4K

Wait for the dark of the waning Moon next weekend to take in this 4K tour of our constant celestial companion.

4. Seven Years of the Sun

Watch graceful dances in the Sun’s atmosphere in this series of videos created by our 24/7 Sun-sentinel, the Solar Dynamic Observatory (SDO).

5. Light ‘Em Up

Crank up the volume and learn about NASA science for this short video about some of our science missions, featuring a track by Fall Out Boy.

6. Bennu’s Journey

Follow an asteroid from its humble origins to its upcoming encounter with our spacecraft in this stunning visualization.

7. Lunar Landing Practice

Join Apollo mission pilots as they fly—and even crash—during daring practice runs for landing on the Moon.

8. Earthrise

Join the crew of Apollo 8 as they become the first human beings to see the Earth rise over the surface of the Moon.

9. Musical Descent to Titan

Watch a musical, whimsical recreation of the 2005 Huygens probe descent to Titan, Saturn’s giant moon.

10. More Movies

Our Goddard Scientific Visualization Studio provides a steady stream of fresh videos for your summer viewing pleasure. Come back often and enjoy.

Read the full version of this article on the web HERE. 

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

Physics: Coins in dry ice

Source: Mr. Hacker on YT

The Unreasonable Effectiveness of Mathematics in  the Natural Sciences

Scholars have often expressed astonishment for how well mathematics works to describe our physical world. In 1960, Eugene Wigner published an article with the title above commenting that

…the mathematical formulation of the physicist’s often crude experience leads, in an uncanny number of cases, to an amazingly accurate description of a large class of phenomena.

Here are some others’ thoughts:

The most incomprehensible thing about the universe is that it is comprehensible.

— Albert Einstein

Physics is mathematical not because we know so much about the physical world, but because we know so little; it is only its mathematical properties that we can discover.

— Bertrand Russell

How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality?

— Albert Einstein

Our physical world doesn’t have just some mathematical properties, it has only mathematical properties.

— Max Tegmark

Physicists may have fallen prey to a false dichotomy between mathematics and physics. It’s common for theoretical physicists to speak of mathematics providing a quantitative language for describing physical reality… But maybe… math is more than just a description of reality. Maybe math is reality.

— Brian Greene

More info at  https://en.wikipedia.org/wiki/The_Unreasonable_Effectiveness_of_Mathematics_in_the_Natural_Sciences

M43 - Part of the same star-forming complex as the Great Orion Nebula (M42)

Two Weeks in the Life of a Sunspot

On July 5, 2017, NASA’s Solar Dynamics Observatory watched AR26665, an active region – an area of intense and complex magnetic fields – rotate into view on the sun. The satellite continued to track the region as it grew and eventually rotated across the sun and out of view on July 17.

Full story

Pluto Found - January 23, 1930

What Will Happen When Betelgeuse Explodes?

“Every star will someday run out of fuel in its core, bringing an end to its run as natural source of nuclear fusion in the Universe. While stars like our Sun will fuse hydrogen into helium and then – swelling into a red giant – helium into carbon, there are other, more massive stars which can achieve hot enough temperatures to further fuse carbon into even heavier elements. Under those intense conditions, the star will swell into a red supergiant, destined for an eventual supernova after around 100,000 years or so. And the brightest red supergiant in our entire night sky? That’s Betelgeuse, which could go supernova at any time.”

One of the most sobering cosmic truths is that every star in the Universe will someday run out of fuel and die. Once its core fuel is exhausted, all it can do is contract under its own gravitational pull, fusing heavier and heavier elements until it can go no further. Only the most massive stars, capable of continuing to fuse carbon (and even heavier elements) will ever create the Universe’s ultimate cataclysmic event: a Type II, or core collapse, supernova. Stars that are fusing carbon (and up) appear to us today as red supergiants, and the brightest red supergiant as seen from Earth is Betelgeuse. Sometime in the next 100,000 years or so, Betelgeuse will go supernova. When it does, it will emit incredible amounts of radiation, become intrinsically brighter than a billion suns and and be easily visible from Earth during the day. But that’s not all.

What’s the full story on what will happen when Betelgeuse goes supernova? Come get the science today!