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This date in science: Kennedy ignites dreams of moon

May 25, 1961. On this date, President John F. Kennedy gave a stirring speech before a joint session of Congress, in which he declared his intention to focus U.S. efforts on landing humans on the moon within a decade. His words ignited the work of a decade, in achieving the dream of a moon landing. Among other things, he said:

I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth.

Full text of Kennedy’s speech inside.

Sunrays seen from Chile

Photo by Yuri Beletsky in the Atacama Desert.

Photo by Yuri Beletsky in the Atacama Desert.

Crepuscular rays, sometimes called sunrays, above the famous volcano Licancabur on the border between Chile and Bolivia.

Total eclipse of sun: August 21, 2017

Path of 2017 total solar eclipse, via Fred Espenak.

Path of 2017 total solar eclipse, via Fred Espenak.

Links to everything you need to know about the total solar eclipse of August 21, 2017. It’ll be the first total solar eclipse visible from the U.S. since 1991 (seen only from part of Hawaii), and first visible from contiguous U.S. since 1979. Start planning now!

Find the Keystone in Hercules

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From mid-northern latitudes, you can easily find the brilliant star Vega in the eastern sky at dusk and nightfall. Vega acts as your guide star the Keystone – a pattern of four stars in the constellation Hercules. The Keystone, in turn, is your ticket to finding a famous globular star cluster in Hercules, otherwise known as Messier 13.

Comets orbiting nearby sunlike star

Illustration of the dust ring surrounding HD 181327. Image via Amanda Smith, University of Cambridge

Illustration of the dust ring surrounding HD 181327. Image via Amanda Smith, University of Cambridge

Astronomers have found the first evidence of icy comets orbiting a sunlike star 160 light-years from Earth.

Top 10 cool things about stars

Stars. Image via NASA

Stars. Image via NASA

Here’s a collection of 10 unexpected, intriguing facts about the stars of our universe – including our sun – that you probably didn’t know!

Star of the week: Polaris is the North Star

Ken Christison captured these glorious star trails around Polaris, the North Star.  He wrote,

Ken Christison captured these glorious star trails around Polaris, the North Star. See more photos from Ken Christison.

The North Star or Pole Star – aka Polaris – is famous for holding nearly still in our sky while the entire northern sky moves around it. Polaris is not the brightest star in the nighttime sky, as is commonly believed. Polaris is only about 50th brightest. Still, this star has been a boon to travelers throughout the Northern Hemisphere, both over land and sea. Follow the links inside to learn more about Polaris, the North Star.

Hubble spies a comet’s rotating jet

s/2016/14/image/a/format/web_print/View full Hubble image. | A narrow, well-defined jet of dust extending from the icy, fragile nucleus of Comet 252P/LINEAR, taken by the Hubble Space Telescope during one of the closest encounters between a comet and our planet.

A rotating jet of dust extending from the icy, fragile nucleus of Comet 252P/LINEAR. The jet is pointed toward about 10 o’clock in the first image, and about 8 o’clock in the second.

In March, Comet 252P/LINEAR passed exceedingly near the Earth. These images show the closest celestial object Hubble has observed, other than Earth’s moon.

Coming to know Corvus the Crow

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One of my favorite constellations, little squarish Corvus the Crow, can be found in the south after sunset at this time of year. It’s not far from the bright star Spica – brightest light in the constellation Virgo the Maiden.

Man-eating crocodiles captured in Florida

Nile crocodile. Nile crocodiles, Crocodylus niloticus, were responsible for at least 480 attacks on people and 123 fatalities in Africa between 2010 and 2014. Image © mariswanepoel / Fotolia

Nile crocodiles were responsible for at least 480 attacks on people and 123 fatalities in Africa between 2010 and 2014. Image © mariswanepoel / Fotolia

Monster Nile crocodiles might be Florida’s newest invasive species.