cherry valley forever
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Peter Solarz
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occasionally subtle
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Mike Driver
2025 on Tumblr: Trends That Defined the Year
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d e v o n

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NASA

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@thegingerbodybuilder
Happy 8th Birthday, Nessie!
The Beauty of Webb Telescope’s Mirrors
The James Webb Space Telescope’s gold-plated, beryllium mirrors are beautiful feats of engineering. From the 18 hexagonal primary mirror segments, to the perfectly circular secondary mirror, and even the slightly trapezoidal tertiary mirror and the intricate fine-steering mirror, each reflector went through a rigorous refinement process before it was ready to mount on the telescope. This flawless formation process was critical for Webb, which will use the mirrors to peer far back in time to capture the light from the first stars and galaxies.
The James Webb Space Telescope, or Webb, is our upcoming infrared space observatory, which will launch in 2019. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born, and how life could form on other planets.
A polish and shine that would make your car jealous
All of the Webb telescope’s mirrors were polished to accuracies of approximately one millionth of an inch. The beryllium mirrors were polished at room temperature with slight imperfections, so as they change shape ever so slightly while cooling to their operating temperatures in space, they achieve their perfect shape for operations.
The Midas touch
Engineers used a process called vacuum vapor deposition to coat Webb’s mirrors with an ultra-thin layer of gold. Each mirror only required about 3 grams (about 0.11 ounces) of gold. It only took about a golf ball-sized amount of gold to paint the entire main mirror!
Before the deposition process began, engineers had to be absolutely sure the mirror surfaces were free from contaminants.
The engineers thoroughly wiped down each mirror, then checked it in low light conditions to ensure there was no residue on the surface.
Inside the vacuum deposition chamber, the tiny amount of gold is turned into a vapor and deposited to cover the entire surface of each mirror.
Primary, secondary, and tertiary mirrors, oh my!
Each of Webb’s primary mirror segments is hexagonally shaped. The entire 6.5-meter (21.3-foot) primary mirror is slightly curved (concave), so each approximately 1.3-meter (4.3-foot) piece has a slight curve to it.
Those curves repeat themselves among the segments, so there are only three different shapes — 6 of each type. In the image below, those different shapes are labeled as A, B, and C.
Webb’s perfectly circular secondary mirror captures light from the 18 primary mirror segments and relays those images to the telescope’s tertiary mirror.
The secondary mirror is convex, so the reflective surface bulges toward a light source. It looks much like a curved mirror that you see on the wall near the exit of a parking garage that lets motorists see around a corner.
Webb’s trapezoidal tertiary mirror captures light from the secondary mirror and relays it to the fine-steering mirror and science instruments. The tertiary mirror sits at the center of the telescope’s primary mirror. The tertiary mirror is the only fixed mirror in the system — all of the other mirrors align to it.
All of the mirrors working together will provide Webb with the most advanced infrared vision of any space observatory we’ve ever launched!
Who is the fairest of them all?
The beauty of Webb’s primary mirror was apparent as it rotated past a cleanroom observation window at our Goddard Space Flight Center in Greenbelt, Maryland. If you look closely in the reflection, you will see none other than James Webb Space Telescope senior project scientist and Nobel Laureate John Mather!
Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
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What’s Up for August 2017
The total solar eclipse on August 21 will trace a narrow path across the nation, although most of the U.S. will see a partial eclipse. Here’s what to do before, during and after the eclipse, plus how you can become a citizen scientist helping us with eclipse observations.
Not everyone can travel to the path of totality, so here are some things you can do whether you see totality or a partial eclipse.
Collecting Citizen Science
Want to be a citizen scientist?
Before the eclipse, make and pack your very own eclipse toolkit, containing a notebook, pen, a clock, a stopwatch, the front page of a newspaper, a thermometer, and a stick with a piece of crepe paper tied to it. Don’t forget your assistant, who will help conduct science observations.
Practice using a citizen scientist phone app, like our GLOBE app to study clouds, air and surface temperatures and other observations. Go to the location where you plan to observe the eclipse and check for any obstructions. You may want to focus on only one activity as the eclipse will last less than 3 minutes … or just really experience the eclipse.
Cell phones don’t take eclipse video! And plan to have your safe eclipse-viewing glasses within reach for before and after totality. Just before totality, if you have a good view of the horizon, look west to see the approaching shadow. After totality, look east low on the horizon for the departing shadow.
During totality, look for stars. You should be able to see the star Regulus in the solar corona or the stars of Orion.
During totality, we may see moving bands of shadows, like on the bottom of a swimming pool.
How dark does it get at totality? Look at the newspaper you brought with you. What is the smallest print you can read?
How much does the temperature drop? Does the wind stop or change direction?
Use your hands, a sheet of paper with a hole in it, a kitchen colander or any other object with one or more holes to use as a pinhole projector. You’ll be able to see the crescent shape of the sun projected through the holes.
Find out more about the eclipse, including eclipse safety, at https://eclipse2017.nasa.gov
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
that tree isn’t high enough stupid!
me as a bat
I’m in love with this bat
“fuck it, good enough.”
Hail the Hexagon…
The full light of our sun allowed the Cassini spacecraft to capture this image of Saturn’s hexagonal polar jet stream, but the sun does not provide much warmth. In addition to being low in the sky (just like summer at Earth’s poles), the sun is nearly ten times as distant from Saturn as from Earth. This results in the sunlight being only about 1 percent as intense as at our planet.
The view was obtained at a distance of approximately 560,000 miles (900,000 kilometers) from Saturn. Image scale is 33 miles (54 kilometers) per pixel.
More info: https://www.nasa.gov/image-feature/jpl/pia21327/hail-the-hexagon
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
@justhiitit
Treadmill run
Warmup: 6 min, .3 miles Work: 30 minutes, 3 miles Cool down: 5 minutes, .23 miles. Total: 41:05 minutes, 3.53 miles. Slowly making progress!
I still laugh at this every single time I see it.
Pushing your knees forward in the Squat.
I’m sure most of you on here know how to squat, or have at least done it before. And I’m sure almost all of you have been told the same cue when squatting.
“Push your hips back”
While I wont say that is the wrong way to squat, I will say that it is an extremely inefficient way to squat. Inefficient meaning you’re dumping energy into less than optimal positions, that will take away from your ability to lift more weight and recruit more muscle engagement.
Above is the way I see most people try to squat. Hips are pushed back, back is hyper extended to keep the chest up, and the knees are behind the toes.
This is how most people should squat. Notice the knees PAST the toes, hips are sunk low, and the back is vertical and FLAT, not arched.
Now I know most of you have probably always heard that the knees coming forward in the squat is bad because it puts too much pressure on your knee joint, but that doesn’t tell the whole story. The knees coming forward in the squat is only dangerous when the squat mechanics are off.
Check out the picture below.
On the left you have an extremely efficient squat position. Notice the bar high on the lifters back directly over the middle of foot (center of gravity) and the back flat and upright, keeping the hips close to the center of gravity. This will allow for maximal quad recruitment when coming out of the bottom position and it will also reduce strain on the back because the vertebra are stacked on top of each other.
On the right you will see the bar out in front of the center of gravity and much lower on the lifters back. The knees behind the toes which cause the hips to be further away from the center of gravity which creates a more horizontal spine. This can cause a lot of stress on the back to keep the bar/chest from falling forward further which would result in the lifter falling down.
To me the answer is obvious, when it comes to efficiency and safety, get that back up, those hips low, and those knees forward.
I gotta say. I’m completely surprised not one person got angry about this.
Down from 221 to 208 since the first of the year. Today I finished my first mile running all the way through in 10 minutes.
240kg/530lbs for a set of 7 off 4"blocks.
A big PB for me, possibly even left one in the tank. Really pleased with this.
Some light-ish paused deadlifts after squats because of my glass hips. 180kg/400lbs for 3x3.