Opening them song for what can only be confirmed (at the time of this posting) is for the first 12 episodes. The song is titled Sidonia and is performed by the band Angela.

 

Sidonia Japanese Lyrics

Sidonia English Lyrics

Ta ga tame ni ware wa yuku
Ta ga tame ni chiri yuku nara
Nani yue niUchikudake
Toki michite
Ikiru tame
Toki hanateSora no kouro wa kaze ni kie
Anjuu wa iku oku kounen saki
Tsuki susumu nara madou na
Iza yukan kishi yoUchikudake (Knights of Sidonia)
Toki michite (knights of Sidonia)
Ikiru tame (Knights of Sidonia)
Toki hanate (Katsuro wa kono te ni)Ta ga tame ni ware wa yuku
Ta ga tame ni chiri yuku naraChikai wo tateru mamonaku
Kono mi wo nagedase
Juuseki to konpai no
Sadame ni wa makeji to

Shuuen wa izuko to furueru na
Tenchou soko wa tada hate no hate
Sugishi ikuta no konsen ni
Chitta tomo wo mune ni

Uchikudake (Knights of Sidonia)
Toki michite (knights of Sidonia)
Ikiru tame (Knights of Sidonia)
Toki hanate (Katsuro wa kono te ni)

Ta ga tame ni ware wa yuku
Ta ga tame ni chiri yuku nara

Chikai wo tateru mamonaku
Kono mi wo nagedase
Juuseki to konpai no
Sadame ni wa makeji to

Hakai no mukou gawa de
Hoshi ga shiraku emu
Saredo dakai no michi
Tooku tooku tooku

Uchikudake (Knights of Sidonia)
Toki michite (knights of Sidonia)
Ikiru tame (Knights of Sidonia)
Toki hanate (Katsuro wa kono te ni)

Uchikudake (Knights of Sidonia)
Toki michite (knights of Sidonia)
Ikiru tame (Knights of Sidonia)
Toki hanate (Katsuro wa kono te ni)

I will go (to fight) for someone (else)
I will fall (on the battlefield) for someone (else)
For what reasonSmash through it
The time has come
In order to survive
Release (your power)The route in the sky has disappeared in the wind
Living peacefully is still a few hundred million light years away
If you’ve decided to push forward, don’t doubt yourself anymore
Come, conquering knightsSmash through it KNIGHTS OF SIDONIA
The time has come KNIGHTS OF SIDONIA
In order to survive KNIGHTS OF SIDONIA
Release (your power)I will go (to fight) for someone (else)
I will fall (on the battlefield) for someone (else)It is almost time to make the oathIt is almost time to make the oath
That (we will) scarifice this body
That (we will) not be daunted by huge resposibility or exhaustion or destiny
Till when do we grieve the dead
The heavens; it just the end of the end
Keeping the memories of all our comrades who have fallen in eth numerous battles so far

Smash through it KNIGHTS OF SIDONIA
The time has come KNIGHTS OF SIDONIA
In order to survive KNIGHTS OF SIDONIA
Release (your power)

I will go (to fight) for someone (else)
I will fall (on the battlefield) for someone (else)

It is almost time to make the oath
That (we will) scarifice this body
That (we will) not be daunted by huge resposibility or exhaustion or destiny

Beyond this destruction, the stars are shining white
Still the road to break (this battle) is far, far, far away

Smash through it KNIGHTS OF SIDONIA
The time has come KNIGHTS OF SIDONIA
In order to survive KNIGHTS OF SIDONIA
Release (your power)

Smash through it KNIGHTS OF SIDONIA
The time has come KNIGHTS OF SIDONIA
In order to survive KNIGHTS OF SIDONIA
Release (your power)

English translation was sourced from http://yumehokori.wordpress.com/