An original sountrack of Space☆Dandy will be released in March 26, 2014. 
Yoko Kanno is involved in only 2 tracks:
16. 知りたい (Shiritai [trans: I wanna know])
(music: Yoko Kanno & Izumi Makura, arrangement: mabanua, lyrics & vocals: Izumi Makura)
23. X次元へようこそ (X Jigen e Yōkoso [trans: Welcome to the X Dimension]) (TV size)
(music & lyrics: Tika Alpha, arrangement: Yoko Kanno, vocals: Yakushimaru Etsuko)
There’s an advertising where you can hear “I wanna know” at the very end:
Sources:
The ending theme of Space☆Dandy “Welcome to the X Dimension” was already present in the first episode broadcast on January 6, 2014.
It’s never easy to tell how much weight an arranger brings to a song written by someone else. Yoko Kanno arranged the song, and it’s a new style she did this time. This funky acid jazz arrangement is not bad at all, and actually it goes well with Yakushimaru Etsuko’s voice and performing.
As for the background music of this first episode, I think we will have to wait for an album to know if Yoko Kanno worked on some tracks, because she’s not credited anywhere, not even in the Space☆Dandy Band.
This song will be released as a single on January 29, 2014.
Yoko Kanno will contribute to some extent to the new Watanabe project Space☆Dandy.
This new anime (katakanized スペース☆ダンディ) will tell the story of an alien hunter named Space Dandy. Remind you something?
A Worldwide simultaneous broadcast began on January 5, 2014 in Japan, USA, Australia, England, France, Germany, Italy, Singapore, Malaysia, Indonesia, Philippines, Thailand, Viet Nam, Taiwan, Hong Kong, Makau, India and Korea! This is probably the first time it happens!
On the music side, it looks like a bit of a mess. 22 musicians are contributing to the project, and among them lies Yoko Kanno (and also Taro Umebayashi who also works for the label Piano). Everything is managed by the music producer Keisuke “Tommy” Tominaga who also works for Piano Inc.
The music is labeled by Flying Dog who created a dedicated website.
Yoko Kanno is not involved in the opening theme but arranged the ending theme entitled「X次元へようこそ」(X jigen e yōkoso [trans: Welcome to the X Dimension]).
It is performed by Yakushimaru Etsuko and will be released as a single in January 29, 2014:
Single「X次元へようこそ/絶対ムッシュ制」(X jigen e yōkoso/Zettai MUSSHU-sei)
2014.01.29 Release
VTCL-35175／￥1,200+tax
01. X次元へようこそ (X jigen e yōkoso [trans: Welcome to the X Dimension])
Music and lyrics : ティカ・α Arrangement : Yoko Kanno
02. 絶対ムッシュ制
Music and lyrics: ティカ・α Arrangement : Etsuko Yakushimaru, Jimanica
03. X次元へようこそ（off vocal）
04. 絶対ムッシュ制（off vocal）
05. X次元へようこそ（TV size）
So far we don’t know if she wrote some background music too.
