5 stories to follow: April 18

One of the blast sites on Boylston Street near the finish line of the 2013 Boston Marathon is investigated by two people in protective suits in the wake of two blasts in Boston Monday, April 15, 2013. (AP Photo/Elise Amendola)

Here are five stories to have on your radar today:

1. What's next for gun control?: After the Senate rejected gun legislation sponsored by Pennsylvania Republican Pat Toomey and West Virginia Democrat Joe Manchin.The bill would have expanded background checks for people purchasing firearms. Though Democratic leaders in the Senate are vowing to bring up the measure again, it appears that, despite a major push for new gun laws after the December massacre in Newtown, significant legislation won't be passed anytime soon. Toomey says it's "time to move on," and the Sunlight Foundation looks at why pro-gun groups have the upper hand.

2. Fertilizer plant blast: An overnight blast at a Fertilizer plant in Waco, Texas, has left several people dead and dozens more injured.

3. Hunt for Boston bombing suspect: Despite news reports Wednesday that an arrest in the Boston Marathon bombings was imminent, but the search for the perpetrators continues. Investigators say surveillance video has captured a suspect with a backpack acting suspiciously. Facial-recognition technology may prove to be a boon to investigators. Meanwhile, the Penn Relays -- which take place next week at Franklin Field -- are on high alert and examining security procedures.

4. Science, tech weeks: There are tons of events to celebrate and learn more about science and techology in Philly for the next 10 days. The Philadelphia Science Festival begins today, and Philly Tech Week starts tomorrow. Check out science festival events here and tech week festivities here.

5. Gosnell trial: Prosecutors will wrap up their case against the West Philadelphia abortion doctor today. The defense is slated to begin presenting evidence Monday.