Old But Gold 💛

When I post Slow Mo Guys videos, it often comes with a warning not to try this at home. For their latest video, that deserves an extra-special mention: seriously, don’t try this. In this video, Dan and Gav explode lithium-ion batteries. In the process, they discover a safety feature - namely vents on one face of the battery. Because runaway thermal reactions (a.k.a. explosions) are a possibility with this type of battery system, consumer-grade batteries are designed to try and prevent extreme damage. One of these outwardly visible safety features are these four vents that release gas when when the battery is too hot. By venting the gas, manufacturers keep the battery from exploding and sending hot chemicals and shrapnel in all directions. Instead the venting gas turns the entire battery into a miniature rocket. (Video and image credit: The Slow Mo Guys)

Largest Batch of Earth-size, Habitable Zone Planets

Our Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in an area called the habitable zone, where liquid water is most likely to exist on a rocky planet.

This exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. In May 2016, researchers using TRAPPIST announced they had discovered three planets in the system.

Assisted by several ground-based telescopes, Spitzer confirmed the existence of two of these planets and discovered five additional ones, increasing the number of known planets in the system to seven.

This is the FIRST time three terrestrial planets have been found in the habitable zone of a star, and this is the FIRST time we have been able to measure both the masses and the radius for habitable zone Earth-sized planets.

All of these seven planets could have liquid water, key to life as we know it, under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.

At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. Because they are located outside of our solar system, these planets are scientifically known as exoplanets. To clarify, exoplanets are planets outside our solar system that orbit a sun-like star.

In this animation, you can see the planets orbiting the star, with the green area representing the famous habitable zone, defined as the range of distance to the star for which an Earth-like planet is the most likely to harbor abundant liquid water on its surface. Planets e, f and g fall in the habitable zone of the star.

Using Spitzer data, the team precisely measured the sizes of the seven planets and developed first estimates of the masses of six of them. The mass of the seventh and farthest exoplanet has not yet been estimated.

For comparison…if our sun was the size of a basketball, the TRAPPIST-1 star would be the size of a golf ball.

Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky. Further observations will not only help determine whether they are rich in water, but also possibly reveal whether any could have liquid water on their surfaces.

The sun at the center of this system is classified as an ultra-cool dwarf and is so cool that liquid water could survive on planets orbiting very close to it, closer than is possible on planets in our solar system. All seven of the TRAPPIST-1 planetary orbits are closer to their host star than Mercury is to our sun.

 The planets also are very close to each other. How close? Well, if a person was standing on one of the planet’s surface, they could gaze up and potentially see geological features or clouds of neighboring worlds, which would sometimes appear larger than the moon in Earth’s sky.

The planets may also be tidally-locked to their star, which means the same side of the planet is always facing the star, therefore each side is either perpetual day or night. This could mean they have weather patterns totally unlike those on Earth, such as strong wind blowing from the day side to the night side, and extreme temperature changes.

Because most TRAPPIST-1 planets are likely to be rocky, and they are very close to one another, scientists view the Galilean moons of Jupiter – lo, Europa, Callisto, Ganymede – as good comparisons in our solar system. All of these moons are also tidally locked to Jupiter. The TRAPPIST-1 star is only slightly wider than Jupiter, yet much warmer. 

How Did the Spitzer Space Telescope Detect this System?

Spitzer, an infrared telescope that trails Earth as it orbits the sun, was well-suited for studying TRAPPIST-1 because the star glows brightest in infrared light, whose wavelengths are longer than the eye can see. Spitzer is uniquely positioned in its orbit to observe enough crossing (aka transits) of the planets in front of the host star to reveal the complex architecture of the system. 

Every time a planet passes by, or transits, a star, it blocks out some light. Spitzer measured the dips in light and based on how big the dip, you can determine the size of the planet. The timing of the transits tells you how long it takes for the planet to orbit the star.

The TRAPPIST-1 system provides one of the best opportunities in the next decade to study the atmospheres around Earth-size planets. Spitzer, Hubble and Kepler will help astronomers plan for follow-up studies using our upcoming James Webb Space Telescope, launching in 2018. With much greater sensitivity, Webb will be able to detect the chemical fingerprints of water, methane, oxygen, ozone and other components of a planet’s atmosphere.

At 40 light-years away, humans won’t be visiting this system in person anytime soon…that said…this poster can help us imagine what it would be like: 

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

Time for another comic on our reddish dwarf planet, Makemake!

(Polaris is pushed for tomorrow ;) )

http://www.space.com/23122-makemake.html

Full trailer up TODAY! Click on the link in our bio to watch! #stem #funny #youtube #badjokes #lab #wine #drinking http://ift.tt/2kXXIDw

For pedestrians, windy conditions can be uncomfortable or even downright dangerous. And while you might expect the buildings of an urban environment to protect people from the wind, that’s not always the case. The image above shows a simulation of ground-level wind conditions in Venice on a breezy day. While many areas, shown in blue and green, have lower wind speeds, there are a few areas, shown in red, where wind speeds are well above the day’s average. This enhancement often occurs in areas where buildings constrict airflow and funnel it together. The buildings create a form of the Venturi effect, where narrowing passages cause local pressure to drop, driving an increase in wind speed. Architects and urban designers are increasingly turning to numerical simulations and CFD to study these effects in urban environments and to search for ways to mitigate problems and keep pedestrians safe. (Image credits: CFD analysis - SimScale; pedestrians - Saltysalt, skolnv)

This post was sponsored by SimScale, the cloud-based simulation platform. SimScale offers a free Community plan for anyone interested in trying CFD, FEA and thermal simulations in their browser. Sign up for a free account here. 

For information on FYFD’s sponsored post policy, click here.

December 17, 1965 – Stunning images of Earth captured by the astronauts of Gemini 7 as their craft raced around the planet.

(NASA/ASU)

Please subscribe, like, comment, and donate! Next (and last) episode April 15, 2017. Starring: Candice Lola Directed by Rebecca Berger Produced by Rebecca Berger and Candice Lola Written by Candice Lola Editing, Color, Sound Design by Rebecca Berger Animation by Rachael K McDonald Links: Music: http://ift.tt/1JICaNj and http://ift.tt/2lquxdO http://ift.tt/2lINlQJ http://ift.tt/2lqtjzr http://ift.tt/2lIL08B http://ift.tt/2lqvuCQ (Donations are always welcome!) http://ift.tt/2lITyw7 http://ift.tt/2lqvQJO