We've all heard that healthy adults should get eight to nine hours of sleep each night to prevent obesity and retain cognitive functions. But an array of new studies suggests those figures might be an hour or two off.
A 2013 poll by the National Sleep Foundation found that people needed seven hours and 13 minutes of sleep to be at their best. (However, 69 percent of people reported getting less sleep than they claimed to need, so take it with a grain of salt.) Other recent studies have found that shooting for around 7 hours of sleep a night might be the healthiest goal — and that going too far under or over that amount can actually contribute to health risks, including diabetes and cardiovascular disease.
A recent study at the University of California San Diego, for example, tracked the sleep habits of 1.1 million people over six years. They found that people who slept between 6.5 and 7.4 hours a night had lower mortality rates than those with less — or more — sleep. Another study, published in the journal Frontiers in Human Neuroscience, found that after seven hours, "increasing sleep was not any more beneficial," Murali Doraiswamy, co-author of the study, told The Wall Street Journal.
The Center for Disease Control and Prevention is currently developing new sleep recommendations, which it hopes to publish by 2015, according to the WSJ. However, a number of doctors caution against changing your sleep habits because of the recent crop of studies, saying that more information is needed. Meghan DeMaria
The Koch brothers may not be settling on a Republican presidential candidate just yet. One day after The New York Times reported that the Kochs were getting behind Wisconsin Gov. Scott Walker, a "top Koch aide" tells Politico the billionaire brothers are going to give Jeb Bush a "chance to audition for the brothers' support."
The reason for the reconsideration, according to Mike Allen: "Bush is getting a second look because so many Koch supporters think he looks like a winner."
It's possible the Kochs really are undecided. It's also possible they're doing some damage control to contain the fallout from the Times story.
Either way, David Koch, fresh off proclaiming Walker would be the nominee, walked back the remark in a statement to Politico. While Walker would make a "terrific" president, he said, "I am not endorsing or supporting any candidate for President at this point." Jon Terbush
Archaeologists have discovered an incredibly rare, advanced weapon, and they found it by accident.
A Russian archaeological team was studying a sabre that was discovered seven years ago in Yaroslavl. They were only conducting a routine examination, but closer inspection revealed that the sabre was actually the oldest crucible steel weapon found in eastern Europe.
— MongolsChinaSilkRoad (@MongolsSilkRoad) April 21, 2015
Asya Engovatova, who led the research, said in a statement that the discovery was "highly unexpected," since the sabre had already been on display at a local museum for seven years. In 2007, Engovatova's team found the weapon at a mass grave site for civilians killed in a massacre in 1238. The site also yielded skeletons and household items, including dishes and jewelry.
Analysis of the sabre revealed that it was a sword made from crucible steel, a rare and expensive material. The archaeologists believe the sabre could have belonged to a wealthy warrior from the army of Batu Khan, who led the 1238 invasion. They also believe the sabre was burned during a ritual before it was buried. There's still much for historians to explore about the weapon, but for now, the sabre has returned to its display at the Yaroslavl Museum. Meghan DeMaria
On Tuesday, the Vatican announced that Pope Francis has accepted the resignation of Bishop Robert Finn, who led the Kansas City/St. Joseph diocese. Finn pleaded guilty in 2012 to charges that he failed to report suspected child abuse to authorities — he waited six months to tell police that Rev. Shawn Ratigan had hundreds of explicit photos on his computer of young girls from around churches where he worked — and was sentenced to two years of probation. Ratigan was given 50 years for child pornography.
— 41 Action News (@41ActionNews) April 21, 2015
Finn, 62, offered his resignation under a section of canon law that allows early departure of duties due to illness or other "grave" reason that renders them unfit for duty. Last month, Pope Francis demoted Cardinal Keith O'Brien of Scotland and stripped him of all priestly "duties and privileges" after O'Brien admitted to sexual misconduct in 2013, but Finn is the first U.S. bishop removed for failing to report a suspected child abuser. Archbishop Joseph Naumman will temporarily lead the Kansas City diocese. Peter Weber
The universe's largest known structure has turned out to be nothing more than a supervoid — a.k.a, a really big hole.
Scientists discovered the supervoid, a blob that's a stunning 1.8 billion light years across, during a recent astronomical survey. Istvan Szapudi, who led the research, told The Guardian that the hole may be "the largest individual structure ever identified by humanity."
— Discovery News (@DNews) April 21, 2015
Szapudi explained that the astronomers had hoped to find the void, because it provides an explanation for why previous reports showed the area as "unusually cool," The Guardian reports. The new research suggests that the "Cold Spot," where the hole was discovered, could be a result of the supervoid draining the energy from light traveling through the region. The void could help explain the universe's formation after the Big Bang, because light photons would lose energy and become cooler after passing through the void, The Guardian explains.
A giant hole may not seem exciting, but for scientists, the rare find is spectacular. "It just pushed the explanation one layer deeper," Roberto Trotta, a cosmologist at Imperial College London, told The Guardian. "Now we have to figure out how does the void itself form." Meghan DeMaria
Former Florida Gov. Jeb Bush (R) will let his super PAC, Right to Rise, do a lot of the heavy lifting (and fundraising) in his undeclared presidential campaign, The Associated Press reports, citing "two Republicans and several Bush donors familiar with the plan." Right to Rise might do many of the things presidential campaigns typically do, like run TV ads and direct-mail campaigns, get-out-the-vote drives, and gather voter data.
"Nothing like this has been done before," campaign spending limit opponent David Keating, president of the Center for Competitive Politics, tells AP. "It will take a high level of discipline to do it." The advantages for Bush are obvious: Money. Super PACs can raise unlimited amounts from people, groups, and corporations, while campaigns must limit donors to $2,700 in the primary and another $2,700 in the general election.
The downside? Once Bush launches his 2016 bid — but not before — he and his campaign can't coordinate with the super PAC. At least not legally. Bush spokeswoman Kristy Campbell downplayed the strategy, telling AP that "any speculation on how a potential campaign would be structured, if he were to move forward, is premature at this time." Read more about Bush's evolving plan, and how it fits with campaign finance laws, at AP. Peter Weber
On Tuesday, a judge in Cairo handed down 20-year prison sentences to ousted President Mohamed Morsi and 12 other defendants, most of them members of Morsi's Muslim Brotherhood, for the death, kidnapping, and torture of protesters in the violent demonstrations that led to overthrow of Morsi, Egypt's first freely elected president. Judge Ahmed Sabry Youssef acquitted the men of murder, which could have led to death sentences.
The sentences can be appealed, but Morsi faces three other trials, and the government of President Abdel Fattah el-Sisi — the former general who overthrew Morsi — has cracked down harshly on the Muslim Brotherhood. The sentencing hearing, from a makeshift courtroom at the national police academy, was broadcast on national TV. Peter Weber
Monday was April 20, and Jon Stewart got all dressed up to celebrate 4/20 with a lighthearted look at pot in the news. CNN, the object of Stewart's frequent mockery, seemed ripe for the picking, but actually turned out substantive reports on the benefits of medical and recreational marijuana for patients and state tax coffers, respectively. "This pot story isn't fun at all," groovy Stewart said on Monday's Daily Show.
That's when Jessica Williams made an appearance as the voice of a sober new generation of pot smokers, playing the foil to Stewart old-school stoner shtick. But since this is The Daily Show, and not sketch comedy, Stewart got in the last jibe, at New Jersey Gov. Chris Christie (R), who it turns out is only against certain suspect forms of raising revenue for his state, regardless of opposition from the feds. —Peter Weber