Happy Tuesday. I did my workout studio's Hyrox-themed class yesterday, which not only left me sore but also with a better understanding of what all the hype in the fitness business is about.

S&P 500 futures ticked higher this morning. The stock market is coming off a winning day.

Here are five key things investors need to know to start the trading day:

Billionaire entrepreneur Elon Musk is combining his rocket company SpaceX with his artificial intelligence startup xAI, he announced yesterday. The tie-up comes ahead of what's expected to be a huge IPO for the merged business.

The tie-up is the largest merger in Musk's portfolio and marries two businesses whose values have soared on the private markets. Nevada public records obtained by CNBC showed that the deal was completed yesterday.

In a blog post, Musk said he was forming "the most ambitious, vertically-integrated innovation engine on (and off) Earth." He said a primary driver for the merger was his quest to build "orbital data centers" — data centers in space. As CNBC's Lora Kolodny and Ari Levy note, SpaceX may represent Musk's clearest path to securing the capital xAI needs to make that dream a reality.

After a rough end to January, stocks kicked off the new trading month with gains yesterday. The Dow Jones Industrial Average added more than 500 points, while the S&P 500 and Nasdaq Composite both climbed more than 0.5%.

Here's what we're following:

• Nvidia shares slipped nearly 3% after a report that the chipmaker's plan to invest $100 billion in OpenAI was up in the air.
• Disney tumbled more than 7% after reporting softness in international visits. Investors are also awaiting a potential announcement on who will succeed Bob Iger as CEO.
• Rare earth stocks including MP Materials and USA Rare Earth advanced in extended trading after President Donald Trump announced the establishment of a critical mineral reserve yesterday.
• Shares of Pfizer and Merck are lower before the bell. That's despite top- and bottom-line beats from both pharmaceutical companies this morning.
• PayPal shares plunged more than 16% in pre-market trading after the company gave a weak profit forecast for 2026 and said HP's Enrique Lores would take over as president and CEO next month.
• Beyond stocks, gold and silver are rebounding this morning after a recent sell-off of the precious metals.
• Follow live markets updates here.

Palantir exceeded expectations on both lines for the fourth quarter yesterday, sending shares up more than 11% in overnight trading. In an interview with CNBC's Morgan Brennan, CEO Alex Karp called Palantir's report "indisputably the best results that I'm aware of in tech in the last decade."

The Denver-based firm posted higher commercial and government revenues than Wall Street expected. Karp said strong demand, paired with Palantir's high engagement in the U.S., has led the defense technology company to delay selling new products to American allies.

Karp also spoke about the ongoing protests against U.S. Immigration and Customs Enforcement, telling CNBC that he thinks protesters should support his company's business with the government. "If you are critical of ICE, you should be out there protesting for more Palantir," he said, adding that Palantir's product "requires people to conform with Fourth Amendment data protections."

Trump announced yesterday that the U.S. and India have reached a trade deal that will see both countries lowering their tariffs on each other's exports. The news comes just days after the European Union made its own trade deal with India.

Under the agreement, India will buy U.S. products "at a much higher level," Trump said on social media. He also said said Indian Prime Minister Narendra Modi committed to "stop" buying oil from Russia. Instead, Trump said New Delhi would purchase more from America — and, possibly, Venezuela.

Meanwhile on Capitol Hill, House Speaker Mike Johnson is trying to advance a funding deal and end the partial government shutdown, which began on Saturday. The Bureau of Labor Statistics said yesterday that shutdown will delay the release of January's jobs report that was scheduled for Friday.

As CNBC's Eunice Yoon reports, consumer sentiment looks just as sour in China as it does in the U.S. That gloom is reflected in the widespread popularity of a frowning horse plushie.

The stuffed animal's downcast appearance was originally due to a manufacturing mistake, according to state media. A factory worker accidentally sowed the toy's smile on upside down, creating what's now known as "the crying horse."

The sorrowful horse has come to represent the downcast sentiment Chinese consumers feel amid deflation and a down economy. As Beijing toy seller Gao Lan put it: "The crying horse reflects how people feel inside."

U.S. store closures are poised to hit three-year lows as the retail industry moves past a string of bankruptcies. Here are the retailers expected to add the most stores this year:

CNBC's Ari Levy, Lora Kolodny, Sean Conlon, Liz Napolitano, Sawdah Bhaimiya, Lillian Rizzo, Julia Boorstin, Yun Li, Lee Ying Shan, Samantha Subin, Kevin Breuninger, Garrett Downs, Eunice Yoon, Melissa Repko and Gabriel Cortes, as well as Reuters, contributed to this report. Josephine Rozzelle edited this edition.