What to know now:

1. Zimmerman selling gun: George Zimmerman, the man  who shot and killed 17-year-old Trayvon Martin as the two scuffled in a Sanford, Fla., neighborhood four years ago, is auctioning off the  gun he used that night. The 9 mm pistol is being sold on the website gunbroker.com. "The firearm for sale is the firearm that was used to defend my life and end the brutal attack from Trayvon Martin," Zimmerman wrote on the auction site.   Zimmerman was found not guilty of second-degree murder and manslaughter in Martin's death.

2. Fire was no accident: A fire that led to a blast at a fertilizer plant that leveled the town of West, Texas, was set intentionally, according to investigators. The 2013 fire and explosion at the plant killed 15 people, 12 of whom were first responders. The town suffered devastating damage – 500  homes and businesses were destroyed. The blast was so powerful it left a 100-foot crater.

3. A Twitter war: It  may be Donald Trump vs.  Hillary Clinton come this fall, but for now Sen. Elizabeth Warren, (D-Mass), is the woman giving Trump some trouble. Warren and Trump got into a fight on Twitter Wednesday with Warren saying Trump only bullies women and Trump asking her why she had time to spend sending out tweets all day. Warren wrote at one point, "Your policies are dangerous. Your words are reckless. Your record is embarrassing. And your free ride is over." Trump countered, "Isn't it funny when a failed Senator like goofy Elizabeth Warren can spend a whole day tweeting about Trump & gets nothing done in Senate?"

4. Trump,  Ryan to meet: Donald Trump is set to meet with Speaker of the House Paul Ryan Thursday in a meeting that could be a bit uncomfortable. Last week Ryan said he was not ready to endorse Trump, the presumptive Republican nominee for president. Trump said this past weekend he was shocked at the comment since he thought Ryan was in his camp.

5. One fast ride: Looking to get from LA to San Francisco in less than six hours?  ]How does 30 minutes grab you. On Wednesday, a company called Hyperloop One demonstrated a propulsion system they hope to perfect that will shoot customers seated in tubes toward their destinations at more than 300 miles per second, a company's spokesman said.  On Wednesday, the sled traveled 105 miles per hour using electromagnets. Hyperloop is owned by SpaceX entrepreneur Elon Musk.

And one more

Officials in Mauritius say  they have found two pieces of an aircraft "most certainly" from missing Malaysian Airlines Flight 370. The discovery brings to five the number of pieces linked to the plane that disappeared  more than two years ago on a flight from Kuala Lumpur to Beijing.  The plane was carrying 239 passengers and crew.

In case you missed it

Life does seem to go this fast, especially when you watch someone grow from age 12 to 20.