Today is the winter solstice, the shortest day of the year, in the northern hemisphere. To mark the occasion and to celebrate the holiday season, Björk has released a new holiday version of the "Solstice" app from Biophilia. The song is based on a poem celebrating the Christmas season by poet/author Sjón, comparing the solar system to a Christmas tree. The new "Solstice" app includes additional features like gameleste sound samples, more festive colors, and, most importantly, the opportunity for fans to create a song and send it to friends as Christmas e-cards.

Björk’s long-time collaborator and friend Sjón originally composed the Christmas poem that inspired “Solstice” at the request of an Icelandic newspaper. The poem, a celebration of light and seasons, compares the solar system with a Christmas tree: at the center of the app is a sun from which the user pulls rays of light to form a circular harp of strings plucked by orbiting planets; tilt the device and the image changes. Björk plays the “Solstice” song with a specially commissioned pendulum-harp, which embodies the idea of gravity that was central to the song’s creation.

"Ever since I saw my friend Sjón's poem 'Solstice,' I got excited about writing a song to it," writes Björk. "I felt it poetically pointed out that the tilt of the earth gives us the seasons and reminds us of our place in the universe. We are a part of a gigantic gorgeous mobile run by physics, solar systems, and, as the poem points out in the end, love. In the poem, Earth´s position in our solar system is compared to a Christmas ornament hanging on a Christmas tree, third from the star. This inspired me to suggest that the app for this would be both 'bird´s eye view' solar system and then from another angle, a Christmas tree."

Read more of what Björk has to say about the app at bjork.com and download "Solstice" on iTunes, where you can also download the full Biophilia app all at once for the first time.

To pick up a copy of the Biophilia album on vinyl and CD in North America, head to the Nonesuch Store, where all CDs, LPs, and DVDs are now 34% off the standard retail price as part of the store's fourth anniversary sale. Biophilia orders also include high-quality, 320 kbps MP3s of the album at checkout.