Shares of Constellation Energy Corp (CEG) tumbled 7.76% in pre-market trading on Tuesday following the release of its first-quarter earnings report, which fell short of analyst expectations. The company, a major player in the energy sector, reported adjusted operating earnings per share of $2.14, missing the consensus estimate of $2.22 according to LSEG IBES data.

The earnings miss comes as a disappointment to investors who were anticipating stronger results from the energy giant. While Constellation Energy's Q1 revenue came in at $6.79 billion, beating analyst estimates of $5.44 billion, the lower-than-expected earnings per share appear to have overshadowed this positive aspect of the report.

Adding to investor concerns, Constellation Energy provided an update on its pending acquisition of Calpine, stating that the deal is expected to complete by year-end. This timeline may be contributing to market uncertainty, as investors assess the potential impact of the acquisition on the company's future performance and financial position.

Despite the negative market reaction, Constellation Energy reaffirmed its full-year 2025 adjusted earnings guidance of $8.90-$9.60 per share. However, this reassurance seems insufficient to calm investor nerves in the face of the Q1 earnings miss and ongoing acquisition proceedings. As the market opens, all eyes will be on Constellation Energy to see if it can recover from this pre-market plunge and how management addresses concerns during any subsequent investor communications.