Here's a roundup of news trending across the nation and world today.

What to know now:

1. Returns Day: If you are planning on returning a gift purchased online, Thursday might not be the day to do it. According to UPS, it's National Returns Day, the day where the company expects it will return to online sellers the greatest number of holiday gifts in a single day. This year the company is estimating they will return 1.3 million packages on Thursday alone.

2. Facebook beating: Chicago police have arrested four people in connection with a "sickening" video posted on Facebook that appears to show the group beating a mentally challenged man. Police report they found the young man wandering on the city's West Side and took him to a local hospital. They later learned of a video that allegedly showed the teen being beaten. According to a Chicago Police Department press release, the four suspects were arrested after a call about another incident involving battery at a residence. While there, police say they saw signs of a struggle and were able to connect the residence and suspects to the man they had found in the streets.

3. Some Macy's closing; Macy's announced Wednesday that it will be closing 63 stores by spring and eliminate 10,000 jobs. Weak sales, the company says, are to blame. Even the chain's e-commerce business, which has been booming, took a hit in November and December. The closures include stores across the country. Final sales will begin Jan. 9, according to the company, and continue for about 12 weeks.

4. Identifying the signal: Scientists say they believe they have pinpointed the origin of a signal from space that has baffled astronomers for years. The signal, sporadic bursts of radio waves, has been traced to a tiny galaxy 3 billion light-years away. Scientists at Cornell University made the find. They believe the signal is coming not from alien life but from a "magnetar," or "a newborn neutron star with a huge magnetic field, inside a supernova remnant or a pulsar wind nebula."

5. Big fish: If you think the last fish you bought was pricey, you may want to stay away from the bluefin tuna. A 466-pound tuna was bought at auction Thursday in Japan for a cool 74.2 million yen, or $632,000. Kiyoshi Kimura, the president of the Shushi Zammai restaurant chain, made the winning bid for the fish caught off the coast of northern Japan's Aomori prefecture. If you were thinking of buying a bit to have for dinner you'd need to fork over about $1,356 a pound.

And one more

A private memorial service for Carrie Fisher and her mother Debbie Reynolds will be held Thursday in Beverly Hills. Fisher, who died on Dec. 27, and Reynolds, who died a day later, will be buried at Forest Lawn Memorial Park in Hollywood Hills.

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