Kim Yong-sun (Korean: 김용선, born February 21, 1991), known professionally as Solar (솔라), is a South Korean singer, songwriter, and actress signed under RBW. She is the leader and main vocalist of girl group Mamamoo and its sub-unit Mamamoo+. She made her solo debut with the single "Spit It Out" on April 23, 2020. She released her first extended play 容: Face with its lead single "Honey" on March 16, 2022. Solar ventured into musical acting through the musical Mata Hari for its 2022 production. Solar will make her film debut with a role as Mi-yeon in horror film The Cursed. Solar also made her debut in Taiwan with a Chinese single "Floating Free" on June 11, 2025.
Kim Yong-sun was born in Gangseo District, Seoul, South Korea, on February 21, 1991, where she lived with her parents and elder sister. She went to Hanyang Women's University with a major in tourism.
2014–2018: Debut with Mamamoo and Solar Emotion project
Solar debuted as a member and vocalist of Mamamoo on June 18, 2014, along with Moonbyul, Wheein, and Hwasa. She made a cameo appearance in the 2015 romance web drama Imaginary Cat as Jung Soo-In. On August 30, 2015, she participated in the television singing show King of Mask Singer. On October 2, she released her first soundtrack "Star" with Kim Min-jae for the tvN drama Second 20s. On October 16, she released the first part of the Solar Emotion project with the song "Lived Like a Fool". On December 11, she released the second part of the musical project with the song "Only Longing Grows".
On March 29, 2016, Solar featured in the single "Love Again" by Yang Da-il. On April 2, Solar was announced to be a part of We Got Married with Eric Nam and appeared in episode 316. The pair completed their last appearance on November 19, 2016, in episode 348. On December 29, 2016, the pair won 'Best Couple Award' at the 2016 MBC Entertainment Awards, which was Solar's first variety show award as an entertainer. She was also nominated for 'Rookie Award (Female) in Variety Show' on the same night.
On July 8, 2016, she released the third part of her project with the song "In My Dreams". On February 21, 2017, Solar released the fourth part of the project with the song "Happy People". On October 17, the fifth part was released, it consisted of two singles "Alone People" and "Autumn Letter". On November 15, she was featured on "Cloudy" by Kiggen.
On April 24, 2018, she released her first solo EP, Solar's Emotion, which included previously released covers of several Korean pop songs and her solo version of Mamamoo's "Star Wind Flower Sun," which she wrote herself. To celebrate the release, she held concerts titled 'Solar Concert Blossom' from April 27 to 29 in Seoul and Busan. On August 22, she featured on Ravi's single "Leopard". On October 13, she featured on Cosmic Girl's single "Lie Ya".
2019–2021: Solarsido, solo debut and variety show appearances
On February 21, 2019, Solar launched her personal YouTube channel called "Solarsido" to celebrate her 29th birthday (Korean age). She gained 1 million subscribers in 9 months and revealed on the show Happy Together that her highest earning was approximately 100 million South Korean won in 1 month just from her channel revenue alone. Solar has continued to upload weekly on her channel and gained over 320 million views.
She made her official solo debut with the single "Spit It Out" which was released with a music video on April 23, 2020. The same day, Solar had her debut stage on Mnet's M Countdown. On April 28, she won her first music show award as a solo artist on SBS MTV's The Show.
On November 8, 2020, Solar joined Boss in the Mirror as 'Idol Boss' in episode 81 to 85. She returned as a fixed guest star and panelist for episodes 107 on May 9, 2021, and would subsequently guest star in the following episodes (107 to 109, 115 to 120, and 124 to 126). She became the photoshoot model for Men's Health magazine alongside fellow boss Yang Chi-seung. On May 12, 2021, it was announced that Solar joined Gummy, Lee Seung-chul, Bae Cheol-soo, Jung Jae-hyung, Kim Hyun-chul, and Kang Seung-yoon on KBS audition program The Song We Loved, New Singer show as a judge, her first time taking on such a role. On July 20, 2021, it was announced that Solar joined JTBC's Poongryu – Battle Between the Vocalist as a judge alongside Song Ga-in, Lena Park, Sung Si-kyung, Kim Jong-jin, Lee Juck, and 2PM's Jang Wooyoung.
On December 25, 2021, Solar won her second award as an entertainer and first solo award as an entertainer as 'Best Entertainer in Show and Variety' at the 2021 KBS Entertainment Awards for her work in The Legend, The New Singer and Boss in the Mirror. During her time as a cast member and guest star, Solar recorded minute ratings of 9.7%, 10.6%, 10.8%, and 12.7%.
2022–2024: 容: Face, theatre debut and continued OST and competition judging appearances
On March 16, 2022, she released her first EP 容: Face and its lead single "Honey". "Honey" was listed as one of the 'Best K-pop Track of 2022' by British magazine Dazed, who described it as a "sweet yet bright and bold song."
On April 6, 2022, South Korean production company EMK Musical announced that Solar would be starring in the 3rd season of the musical Mata Hari as the titular character. The musical ran from May 28 to August 15, 2022, with her performance receiving acclaim from critics. Yang Hyungmo reviewed the performance for Sports Donga, stating that her clear notes and drawn tones exceeded expectations, and she "tore up" the stage. Jo Suhyun noted for Star Daily Korea that it was hard to believe it was her first musical, highlighting her strong presence and singing skills. For her performance, she was nominated for the Best Female Newcomer Award at the 7th Korea Musical Awards on December 20.
On June 1, 2022, Solar was announced to join as a cast member for Season 2 of the popular Korea's first ghost story storytelling program Midnight Ghost Story (also known as Late Night Ghost Talk). She joined actor Lee Yi-kyung, entertainer Kim Sook and Kim Gura as MC and storyteller. First broadcast aired on June 9, 2022, and the show concluded on February 23, 2023. Solar was known as Fully Paid Fairy for obtaining 44 candles in 3 different episodes, the first and only cast member to achieve this. Solar was regarded for her realistic acting, proper diction and ASMR like storytelling, capturing the hearts of viewers.
On August 10, 2022, Solar was announced to join as a judge for JTBC's A Star Is Born alongside Jung Jae-hyung, Sung Si-kyung, Jang Min-ho, Defconn, Yoo Se-yoon, and Kim Feel. On August 22, it was announced that Solar and Mamamoo groupmate Moonbyul would be debuting in the sub-unit group Mamamoo+. The duo released their first single, "Better" featuring rapper Big Naughty, on August 30, 2022.
In October 2022, Solar released the single "After Love" from the Casting in the Corner project with Yesung. The song was a remix of the 2006 version and was released on October 20. On December 28, 2022, Solar released "Paradise" for Channel S' DJ Survival competition show Wet!: World EDM Trend. On March 12, 2024, she released "Eternal" for the OST of Pandora: Beneath the Paradise.