A SpaceX Falcon 9 rocket launches the NROL-76 spy satellite for the U.S. National Reconnaissance Office from NASA's Kennedy Space Center in Cape Canaveral, Florida on May 1, 2017.
Credit: SpaceX

SpaceX successfully launched its first national-security mission (and landed the rocket to boot), Virgin Galactic's new SpaceShipTwo tested its "feathering" re-entry system for the first time, and NASA's Cassini probe made a surprising discovery at Saturn. Here are the most interesting things that happened in the universe this week.

SpaceX launches first mission for U.S. military

A SpaceX Falcon 9 rocket lifted off from the Kennedy Space Center in Florida on Monday (May 1) to boost a classified spy satellite into orbit for the U.S. military — the first national-security mission for SpaceX. The rocket's first stage then turned around and touched down at a nearby landing pad. [Full Story: SpaceX Launches US Spy Satellite on Secret Mission, Nails Rocket Landing]

New SpaceShipTwo tests out re-entry system for first time

Virgin Galactic's second SpaceShipTwo took to the skies over Mojave, California on Monday (May 1) for the first test flight of the craft's atmospheric re-entry system, which was modified after a fatal test flight in 2014 destroyed the original ship. [Full Story: Virgin Galactic's SpaceShipTwo Makes 1st Test Flight of Revamped Re-Entry System]

Cassini finds the gap between Saturn and its rings is eerily silent

Researchers monitoring the Cassini spacecraft were surprised to find almost no dust and debris in the previously unexplored zone between Saturn and its rings during the spacecraft's first dramatic dive through the 1,200-mile-wide (2,000 kilometers) gap. You can hear the strange lack of impacts in a new NASA video. [Full Story: Hear Saturn's 'Big Empty' from Cassini, Which Just Made 2nd Ring Dive]

See what Cassini saw during its epic dive

An amazing new video shows just what NASA's Cassini spacecraft saw during its first "Grand Finale" dive between Saturn's cloud tops and the gas giant's rings last week. [Full Story: Wow! Cassini's Bird's-Eye View of Saturn Plunge Astonishes in New Video]

Kamikaze Starshot?

The Breakthrough Starshot project aims to send tiny robotic probes zooming past nearby alien worlds to hunt for signs of life and gather other data. But the scientific return would be even greater if some of the fast-moving 1-gram spacecraft actually slammed into their target worlds, some researchers said. [Full Story: Kamikaze Starshot: Will Some Interstellar Probes Slam into Their Target Planets?

Another twist in the hunt for dark matter

A mysterious abundance of high-energy light near the Milky Way's core likely isn't a sign of elusive dark matter after all, a new study suggests. [Full Story: 'Excess' Gamma-Rays Likely Not Sign of Dark Matter After All

NASA gets some good budget news

A long-overdue fiscal year 2017 spending bill unveiled May 1 will provide NASA with $19.65 billion, more than $600 million above the original request for the agency by the previous administration. [Full Story: NASA Receives More Than $19.6 Billion in 2017 Omnibus Spending Bill]

A tsunami of gas 200,000 light-years wide

A wave of hot gas twice as wide as our Milky Way galaxy roils the nearby Perseus galaxy cluster, a new study reveals. [Full Story: Gigantic X-Ray Tsunami Rolls Through Galaxy Cluster (Video, Photos)

Why 'Star Wars' still has a hold on us 40 years later

A long, long time ago — 40 years ago this month, actually — an initially small group of theatergoers was transported to a galaxy far, far away, heralding the birth of the "Star Wars" universe. [Full Story: Why the Force Is Still Strong with 'Star Wars' Fans

Spot the planets: May skywatching guide

Here's how to view Mercury, Venus, Mars, Jupiter and Saturn in the night sky this month, along with the eye-catching conjunctions some of these planets will have with Earth's moon. [Full Story: The Brightest Planets in May's Night Sky: How to See them (and When)

Hundreds of galaxies, no guardians in sight

As Star-Lord and his team head to the big screen this weekend to guard a galaxy in the Marvel universe, new images from the Hubble Space Telescope remind us that there are far more galaxies in our own universe without any superheroes to protect them from villains. [Full Story: Paging Star-Lord! Hubble Spies Hundreds of Galaxies That Need Guarding

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