Michelle Obama's 50th birthday party featured a 30-minute performance by Beyonce. Credit: Eroteme.co.uk/ Bauer Griffin; Beyonce.com

Mobama's Massive Bash! First Lady Michelle Obama celebrated her 50th birthday with a celeb-filled birthday party on Saturday, Jan. 18, featuring about 500 guests a source tells Us Weekly. 

Grammy-winning artist Ledisi opened out the night, but then handed the microphone over to Beyonce, who performed with a full band for about 30 minutes. 

Though the guests were asked to keep the evening's festivities quiet, the "Drunk in Love" singer, 32, posted several shots on her official tumblr account, including one of her in a short, sparkly dress and heels petting the Obamas' new dog Sunny. 

The mother of 2-year-old Blue Ivy Carter also posted pictures of her little tot visiting the White House in a white dress, admiring the large Christmas tree and playing with Sunny herself. 

John Legend and new wife Chrissy Teigen also attended the festivities, and Legend, 35, personally sang "Happy Birthday" to the First Lady. 

Michelle's doting husband, Barack Obama, acted as the evening emcee, giving an adorable toast once the birthday cake was brought out. 

The partying ran until around 4 a.m. and featured DJ Cassidy spinning music after the live performances ended. Beyonce brought her mother Tina Knowles, who recently had her own big 60th birthday party in New Orleans, and her sister Solange Knowles

Other celebrities in attendance included Paul McCartney and his wife Nancy Shevell, Samuel L. Jackson, Bill and Hillary Clinton, Mary J. Blige, Ashley Judd, Angela Bassett, Jennifer Hudson, Gayle King, Smokey Robinson, Gladys Knight, and Steve Harvey