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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.

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!

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!

Is Europa’s ocean like Earth’s?

This image shows a view of the trailing hemisphere of Jupiter's ice-covered satellite, Europa, in approximate natural color. Long, dark lines are fractures in the crust, some of which are more than 3,000 kilometers (1,850 miles) long.   Image via Galileo spacecraft in 1996.

Jupiter’s ice-covered satellite, Europa, in approximate natural color. Image via Galileo spacecraft in 1996.

New research finds the ocean on Jupiter’s moon Europa could have the necessary balance of chemicals for life, even without active volcanoes.

Only 2 full moons in a season possible?

Photo via Tim Geers

Photo via Flickr user Tim Geers

The May 21 Blue Moon carries that name because it’s the 3rd of 4 full moons in a season. But can a season have just 2 full moons?

New Horizons, heading out, spies 1994 JR1

The New Horizons spacecraft has now obtained 2 views of 1994 JR1, as it heads outward in our solar system. It obtained the newest image  with the spacecraft's Long Range Reconnaissance Imager (LORRI) on April 7-8 from a distance of about 69 million miles (111 million km).

The New Horizons spacecraft has now obtained 2 views of 1994 JR1, as it heads outward in our solar system. It obtained the newest image with the spacecraft’s Long Range Reconnaissance Imager (LORRI) on April 7-8 from a distance of about 69 million miles (111 million km).

New Horizons imaged this distant Kuiper Belt Object twice. It has learned its location and spin, and dispelled a theory that 1994 JR1 is a quasi-satellite of Pluto.

Giant impacts typical for Earth-like worlds

Artist’s concept of a celestial body roughly the size of Earth's moon slamming into a body the size of Mercury.  Image via NASA/JPL-Caltech.

Artist’s concept of a celestial body roughly the size of Earth’s moon slamming into a body the size of Mercury. A giant impact such as this one, early in the history of our solar system, is thought to have created Earth’s moon. Image via NASA/JPL-Caltech.

An advanced computer simulation suggests that newly forming Earth-like worlds are likely to suffer a giant impact, like that thought to have created our moon.

Pleiades setting through Sappho’s eyes

Detail from a portrait of a young woman - A fresco from Pompeii - thought to be Sappho via Museo Archeologico Nazionale (Naples) via Wikimedia Commons.

Detail from a portrait of a young woman – from a fresco – thought to be Sappho. Via Museo Archeologico Nazionale (Naples) and Wikimedia Commons.

Sappho, a renowned poet of ancient Greece, wrote of the Pleiades star cluster setting at midnight. Scientists have wondered, what time of year did she see it?

A new binocular comet before dawn

View larger. | Comet C/2013 X1 (PanSTARRS) captured earlier this year by Efraín Morales, of the Sociedad de Astronomía del Caribe.

Comet C/2013 X1 (PanSTARRS) captured earlier this year by Efraín Morales of the Sociedad de Astronomía del Caribe.

Comet C/2013 X1 (PanSTARRS) is now visible in binoculars and telescopes for Northern Hemisphere observers. It is approaching Earth and will pass distantly, at over 59 million miles (95 million km) from our planet, in late June, 2016. This post has charts and other information that can help you spot the comet in the coming weeks!

Mars is bright! Here’s why

Earth will between between the sun and Mars on May 22, 2016.  Then, the distance between our two worlds will be at its least for this two-year period, and Mars will appear brightest in our sky.  Image via Fourmilab.

Earth will pass between between the sun and Mars on May 22, 2016. Then, the distance between our two worlds will be at its least for this two-year period, and Mars will appear brightest in our sky. Image via Fourmilab.

We’re beginning to get questions about that red “star” in the east each evening. It’s Mars! We’ll pass between Mars and the sun this weekend.