5 things you need to know Thursday

Space shuttle Challenger disaster remembered

Thirty years ago Thursday, the space shuttle Challenger blasted off at 11:38 a.m. ET. Then, 73 seconds after liftoff, a fireball engulfed the shuttle. As a horrified America watched on live TV, the orbiter broke apart, dooming its crew of seven, including high school teacher Christa McAuliffe, who was supposed to become the first civilian in space. The accident, which was eventually blamed on failed rocket O-rings as well as pressure within NASA to keep launches on schedule, forced a reassessment of the shuttle program and the dangers inherent in human spaceflight. As it does each year on the Challenger anniversary, NASA's Day of Remembrance will honor the Challenger victims as well as the lost crews of the Columbia and Apollo 1 and other astronauts killed in the line of duty.

Last GOP debate before the Iowa caucus

The Republican presidential field (most of them, that is) gathers Thursday night in Des Moines for the final debate before Iowans kick off 2016 voting with caucuses Monday night. The prime-time debate will be at 9 p.m. ET, while the undercard starts at 7 p.m. ET. Both debates will be televised by Fox News. Donald Trump isn't participating, due to his ongoing feud with the network and moderator Megyn Kelly. You can also live stream the debates for free at FOXNews.com and on mobile devices. Additionally, Google, which is co-hosting the debate with Fox, is launching a new online feature that allows the campaigns to post content — including videos, text and even real-time responses to questions — which will appear in a window alongside relevant search results. To see the experimental Google content, search "debate."

Tech earnings: Microsoft, Amazon take their turn

This week's parade of earnings reports by tech giants, which are closely watched by investors as a gauge of the industry's health, continues Thursday when Microsoft and Amazon weigh in. Microsoft, which reports fiscal second-quarter results after the bell, has been trying under CEO Satya Nadella to become more nimble and technologically adventurous. Meanwhile, after a jump of 3 million new Prime customers the week before Christmas, analysts are expecting strong fourth-quarter results from Amazon. Thursday's reports follow ones earlier in the week from Apple, Facebook, Twitter and others.

Delaware state House to vote on repeal of death penalty

Delaware's House of Representatives is scheduled to vote Thursday on a bill to repeal the state's death penalty law. The state Senate passed the repeal bill in April, and Gov. Jack Markell has said he will sign it if it passes. Even if the bill fails, Delaware's death penalty could be affected by the courts: A judge on Monday asked the state Supreme Court to consider whether Delaware's death penalty law is constitutional in light of two recent U.S. Supreme Court rulings. Delaware is one of only three states that allow judges to override a jury's recommendation of life and impose a death sentence.Thirty-one states currently have the death penalty, according to the Dealth Penalty Information Center.

Senate committee holds hearing on Obama's new retirement proposals

The Senate Finance Committee will hold a hearing Thursday on retirement security, days after President Obama’s announcement of a new push to expand Americans’ retirement savings. The Republican chairmen of the tax-writing committees of Congress, who have jurisdiction over retirement plan rules and are holding the hearing, have been working on their own proposals, separate from what the White House previewed on Monday. The administration says Obama’s proposed changes could help 30 million American workers. Obama will fully outline his proposals in the 2017 budget, which he'll submit to Congress next month.

And the essentials:

Weather: A soggy Thursday is on tap for the Southeast and the Northwest while light snow falls in the Great Lakes.

Stocks: Wall Street was on track for a higher start Thursday; Asia markets declined.

TV Tonight: Wondering what to watch tonight? TV critic Robert Bianco looks at Legends, 100 and London Spy.

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