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The world watched on television as Neil Armstrong took the first steps on the moon's surface on July 20, 1969.  It was the first time humans walked another world.  As he stepped onto the lunar surface, Armstrong said, "That is one small step for [a] man, one giant leap for mankind."

Today in science: 1st footsteps on moon

Today is the 47th anniversary of humanity’s historic first steps on the moon. The story in pictures, here.

Artist’s impression of the water snowline around the young star V883 Orionis, as detected with ALMA.
Credit: A. Angelich (NRAO/AUI/NSF)/ALMA (ESO/NAOJ/NRAO)

Astronomers see a star’s water snow line

First distinct (resolved) observation of a water snow line – aka a frost line – the distance from a star where temperatures drop so low that water turns to ice.

Scientists from NASA's New Horizons mission used state-of-the-art computer simulations to show that the surface of Pluto's heart-shaped Sputnik Planum region is covered with churning ice "cells." These icy cells are geologically young, less than a million years old. The scene above is about 250 miles (400 km) across. It uses data from New Horizons' July 14, 2015 flyby of Pluto. Image via NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

Video takes you to Pluto’s surface

New video released on 1-year anniversary of New Horizons’ visit to Pluto. It lets you ride aboard a Pluto spacecraft and then plunge toward its surface!

Via  NASA/JPL/SSI/CICLOPS / Mother Jones

Today in science: The day Earth smiled

Anniversary of 3rd-ever image of Earth from the outer solar system, acquired by the great Cassini spacecraft, as we Earth citizens cast our thoughts spaceward.

Image montage showing the Maunakea Observatories, Kepler Space Telescope, and night sky with K2 Fields and discovered planetary systems (dots) overlaid. An international team of scientists discovered more than 100 planets based on images from Kepler operating in the ‘K2 Mission’. The team confirmed and characterized the planets using a suite of telescopes worldwide, including four on Maunakea (the twin telescopes of Keck Observatory, the Gemini-North Telescope, and the Infrared Telescope Facility). The planet image on the right is an artist’s impression of a representative planet.
Image via Karen Teramura, IFA / Miloslav Druckmuller / NASA /  W.M. Keck Observatory.

Wow! Another 104 confirmed exoplanets

That’s from 197 new exoplanet candidates. In its extended (K2) mission, the Kepler space telescope has been looking toward cool, small, red dwarf-type stars.

Hubble Space Telescope image of the giant elliptical galaxy ESO 325-G004, in the galaxy cluster Abell S0740, over 450 million light-years away. Giant elliptical galaxies like this one typically don't form many new stars. Image via HubbleSite.

Why galaxies stop making stars

Nature and nurture in the evolution of galaxies, and what those factors mean with respect to whether galaxies continue forming stars, or not.

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Watch Mercury and Venus set

What are the odds? Peter Lowenstein caught Venus and Mercury on the evening of their conjunction – July 16, 2016 – setting through a thin break in the clouds.

rosetta-1-5-2016-ESA

Farewell, Rosetta comet mission

Rosetta and its instruments have been in harsh outer space for 12 years, the last 2 of which have been in the dusty realm of a comet near the sun.

This artist's illustration shows a narrow beam generated by the merger of two neutron stars and a resulting gamma-ray burst (GRB). Astronomers used several telescopes, including Chandra, to determine that these violent stellar mergers produce very narrow jets by studying the gamma-ray burst called GRB 140903A.  The implication of this result is that a vast majority of these events will go undetected since most will not be directed along the line of sight towards Earth necessary for detection by telescopes. The smaller panels show an optical view of GRB 140903A (left) and an X-ray view from Chandra (right). Image via Chandra X-Ray Observatory.

Gamma ray bursts and pencil-thin jets

Stellar mergers that cause gamma ray bursts might make pencil-thin jets. If true, since most jets won’t be pointed our way, we’ll see no sign of most mergers.

This is one slice through the map of the large-scale structure of the Universe from the Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey. Each dot in this picture indicates the position of a galaxy 6 billion years into the past. The image covers about 1/20th of the sky, a slice of the Universe 6 billion light-years wide, 4.5 billion light-years high, and 500 million light-years thick. Colour indicates distance from Earth, ranging from yellow on the near side of the slice to purple on the far side. Galaxies are highly clustered, revealing superclusters and voids whose presence is seeded in the first fraction of a second after the Big Bang. This image contains 48,741 galaxies, about 3% of the full survey dataset. Grey patches are small regions without survey data. Image via Daniel Eisenstein and SDSS-III.

1.2 million galaxies in 3D

A new map of the universe – based on observations of 1.2 million galaxies – confirms cosmologists’ theories about the web of galaxies making up our universe as a whole.