Students Protest Over Gun Laws, Jennifer Lawrence Tells Critics to 'Get a Grip', Birth of a Supernova Witnessed: P.M. Links

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  NASA

  Students from the Parkland high school where a mass shooter killed 17 people last week, protested at the Florida state capitol, demanding a ban on weapons like the one that killed their classmate. Student activists from around the country joined in with "walkouts" of their own.

• Police in California said they may have thwarted a school shooting after a resource officer reported a "disgruntled student" who threatened a school shooting; a "collection of weapons" was allegedly found in his home.
• Port Authority police arrested 19-year-old delivery man Bruce Lee after he tried to bike through the Lincoln Tunnel.
• Jennifer Lawrence responded to critics of a dress she wore in London, telling them to "get a grip."
• Recep Erdogan says Turkey will work on developing unmanned tanks.
• Snapchat responds to a Change.org petition about its latest redesign.
• A self-taught astronomer became the first person to witness the surge of light at the birth of a supernova when he captured images of 2016gkg.