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Nice

Scans of the inside covers of Strang’s Calculus, which you can legally-download for free here from the MIT website. This is my all-time favorite math or physics textbook. Scanned it so I could cut and paste it into my new sketchbook, wanna try and make a ~cool artistic~ reference poster out of it, ‘cuz I’ve been real into that idea since I took notes about rings for the algebra midterm on a big piece of watercolor paper.

2017 January 14

Stardust in the Perseus Molecular Cloud Image Credit & Copyright: Lorand Fenyes

Explanation: Clouds of stardust drift through this deep skyscape. The cosmic scene spans nearly 2 degrees across the Perseus molecular cloud some 850 light-years away. A triangle of dusty nebulae reflecting light from embedded stars is captured in the telescopic field of view. With a characteristic bluish color reflection nebula NGC 1333 is at left, vdB13 at bottom right, and rare yellowish reflection nebula vdB12 lies at the top. Stars are forming in the Perseus molecular cloud, though most are obscured at visible wavelengths by the pervasive dust. Still, hints of contrasting red emission from Herbig-Haro objects, the jets and shocked glowing gas emanating from recently formed stars, are evident in NGC 1333. At the estimated distance of the molecular cloud, legs of the triangle formed by the reflection nebulae would be about 20 light-years long.

∞ Source: apod.nasa.gov/apod/ap170114.html

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Four Dancers by Edgar Degas

Medium: pastel

D

Space station flyover of Gulf of Aden and Horn of Africa

European Space Agency astronaut Samantha Cristoforetti took this photograph from the International Space Station and posted it to social media on Jan. 30, 2015. Cristoforetti wrote, “A spectacular flyover of the Gulf of Aden and the Horn of Africa. #HelloEarth”

Image credit: NASA/ESA/Samantha Cristoforetti

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800-Year-Old Skeleton Yields Genome of Deadly Infection

Keep reading

Hubble Chases a Small Stellar Galaxy in the Hunting Dog

by NASA’s Marshall Space Flight Center   On a clear evening in April of 1789, the renowned astronomer William Herschel continued his unrelenting survey of the night sky, hunting for new cosmic objects — and found cause to celebrate! He spotted this bright spiral galaxy, named NGC 4707, lurking in the constellation of Canes Venatici or The Hunting Dog. NGC 4707 lies roughly 22 million light-years from Earth. NGC stands for “New General Catalogue of Nebulae and Clusters of Stars.” Over two centuries later, the NASA/ESA Hubble Space Telescope is able to “chase down” and view the same galaxy in far greater detail than Herschel could, allowing us to appreciate the intricacies and characteristics of NGC 4707 as never before. This striking image comprises observations from Hubble’s Advanced Camera for Surveys (ACS), one of a handful of high-resolution instruments currently aboard the space telescope. Herschel himself reportedly described NGC 4707 as a “small, stellar” galaxy; while it is classified as a spiral (type Sm), its overall shape, center, and spiral arms are very loose and undefined, and its central bulge is either very small or non-existent. It instead appears as a rough sprinkling of stars and bright flashes of blue on a dark canvas. The blue smudges seen across the frame highlight regions of recent or ongoing star formation, with newborn stars glowing in bright, intense shades of cyan and turquoise. 

Pulsars: How The First ‘False Alien’ Signal Opened Up A New World In Astronomy

“In 1967, a radio source emitting regular, 0.04-second long pulses every 1.3373 seconds was found for the first time using a scintillation array. After the “noise” explanation was ruled out, the next thing people turned towards were intelligent extraterrestrials. There was no natural mechanism in existence that would have explained it at that time, so turning to aliens was logical, if ultimately incorrect.”

Observations that surprise us, of a phenomenon we weren’t expecting and don’t have an explanation for, are some of the most exciting things we can encounter in astronomy. In 1967, regularly pulsing radio sources, discovered without any expectation, provided exactly that. It wasn’t noise; it was definitely a robust, repeatable observation; so what was it? While our imaginations might have run to aliens initially, further developments quickly showed that this was a ball of rapidly rotating neutrons, more massive than even the Sun but only a few kilometers in diameter. These pulsars, as they’re now know, are ubiquitous and come about from the corpses of core-collapse supernova. Could this be a harbinger of what we can expect from the ‘alien megastructure’ controversy?

Come find out how the first ‘false alien’ signal from astronomy opened up a whole new field of science for us to investigate!

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A giant predatory lizard swam in Antarctic seas near the end of the dinosaur age http://www.geologypage.com/2016/11/giant-predatory-lizard-swam-antarctic-seas-near-end-dinosaur-age.html

November 14, 1969 – Thirty-six-and-a-half seconds after the launch of Apollo 12, the space vehicle triggered a lightning discharge through itself and down to the earth through the Saturn’s ionized plume. Protective circuits on the fuel cells in the Service Module falsely detected overloads and took all the fuel cells offline, as well as much of the Command/Service Module instrumentation. At 52 seconds after liftoff, a second strike knocked out the “8-ball” attitude indicator. The telemetry stream at Mission Control was garble, but Apollo 12 continued to fly correctly. The strikes had not affected the Saturn V rocket’s Instrument Unit.

000:09:02 Conrad (onboard): I think we got hit by lightning.

000:09:04 Gordon Bean (onboard): I do, too.

000:09:06 Gordon (onboard): Something took care of those panels, I’ll say that for it.

Pete Conrad from the 1969 technical debrief: “Because I could see outside, I made the comment to them several times. I told the ground that I thought we had been hit by lightning. I was the only one that had any outside indications. Dick didn’t note anything over his little hole in his center window. I was the only one who noticed anything and that was only the first time. I was aware that something external to the spacecraft had happened. I had the decided impression that I not only saw it, but felt it and heard it.”

Alan Bean from the 1969 technical debrief: “I knew we had power, so I didn’t want to make any changes. I figured we could fly into orbit just like that and that’s exactly what we did. The ground came up a little later and said to put the fuel cells back on the line. I was a little hesitant about doing that, because I didn’t understand that we had been hit by lightning. I gave it a go and, sure enough, things started working very well after that.”

(NASA/Wikipedia/NASA)