Music
Alien's score was written by Jerry Goldsmith and conducted by Lionel Newman. In 1979, Fox released a 12" vinyl record (LP) of the soundtrack. In 1988, Silva Screen produced the first CD version. On November 20th, 2007, the 2-disc Complete Edition came out. It included all the unused cues created by Goldsmith as well as the original 1979 soundtrack. Shown below are details on these, the numerous bootlegs that have been floating around, and the Alien Trilogy CD.
1979 Vinyl LP

1. Main Title (3:30)
2. The Face Hugger (2:32)
3. Breakaway (3:00)
4. Acid Test (4:35)
5. The Landing (4:29) --End Side 1
6. The Droid (4:40)
7. The Recovery (2:44)
8. The Alien Planet (2:28)
9. The Shaft (3:57)
10. End title (3:02)

Total Running Time - 34:57

Silva Screen 1988 CD

1. Main Title (3:30)
2. Face Hugger (2:32)
3. Breakaway (3:00)
4. Acid Test (4:35)
5. The Landing (4:29)
6. The Droid (4:40)
7. The Recovery (2:44)
8. The Alien Planet (2:28)
9. The Shaft (3:57)
10. End Title (3:02)

Total Running Time - 35:28

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2007 Complete Edition

Disc 1: Complete Original Score + Rescored Alternate Cues

1. Main Title (4:12)
2. Hyper Sleep (2:46)
3. The Landing (4:31)
4. The Terrain (2:21)
5. The Craft (1:00)
6. The Passage (1:49)
7. The Skeleton (2:31)
8. A New Face (2:34)
9. Hanging On (3:39)
10. The Lab (1:05)
11. Drop Out (0:57)
12. Nothing To Say (1:51)
13. Cat Nip (1:01)
14. Here Kitty (2:08)
15. The Shaft (4:30)
16. It's A Droid (3:28)
17. Parker's Death (1:52)
18. The Eggs (2:23)
19. Sleepy Alien (1:04)
20. To Sleep (1:56)
21. The Cupboard (3:05)
22. Out The Door (3:13)
23. End Title (3:09)
24. Main Title (rescored alternate) (4:11)
25. Hyper Sleep (rescored alternate) (2:46)
26. The Terrain (rescored alternate) (0:58)
27. The Skeleton (rescored alternate) (2:30)
28. Hanging On (rescored alternate) (3:08)
29. The Cupboard (rescored alternate) (3:13)
30. Out The Door (rescored alternate) (3:02)

Disc Time: 76:54

Disc 2: 1979 Movie Soundtrack + Bonus Cues

1. Main Title (3:37)
2. The Face Hugger (2:36)
3. Breakaway (3:03)
4. Acid Test (4:40)
5. The Landing (4:31)
6. The Droid (4:44)
7. The Recovery (2:50)
8. The Alien Planet (2:31)
9. The Shaft (4:01)
10. End Title (3:08)
11. Main Title (film version) (3:44)
12. The Skeleton (alternate take) (2:35)
13. The Passage (demonstration excerpt) (1:54)
14. Hanging On (demonstration excerpt) (1:08)
15. Parker's Death (demonstration excerpt) (1:08)
16. It's a Droid (unused inserts) (1:27)
17. Eine Kleine Nachtmusik (source) (1:49)

Disc Time: 49:24

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"Directors and editors use temporary music and sometimes it's the kiss of death for a composer. I used to hate it, because I would want to see the picture first without any music. Sometimes they temp-tracked it with music I had written for other pictures, which makes it even worse because I know what the music was originally written for. I had this happen on Alien. They temp-tracked that whole picture with my music. There's one sequence with a cue from Freud, and the director and producer said, 'Isn't that wonderful?' and I didn't agree. They had been living with this music for months, and they were used to it. So I wrote a new piece, and, naturally, I thought it was wonderful. Well, the whole score was eventually emasculated. Half of the music didn't end up where it was supposed to go, and they would end up going to Universal and actually buying that piece of music from Freud and putting it in Alien. This was after the picture was previewed and unbeknownst to me, I was furious! Anyway, there was nothing I could do about it."
-- Jerry Goldsmith
English Bootlegs

1. Main Title (4:13)
2. The Ship Awakens (2:42)
3. The Landing (4:34)
4. Inside the Alien Ship (8:58)
5. The Egg Chamber (2:36)
6. Face Hugger (3:08)
7. Molecular Acid (0:37)
8. Waiting (1:04)
9. Search for the Face Hugger (0:54)
10. Take Off (4:31)
11. Burial in Space (1:51)
12. The Search Begins (1:01)
13. Death of Brett (2:08)
14. The Plan - Mother (1:31)
15. Search in the Shaft (4:33)
16. Ash in a Robot (3:29)
17. Death of Lambert and Parker (1:53)
18. Destruct System Activated (3:29)
19. Last Survivors (1:55)
20. Alien in the Pod (3:07)
21. Final Confrontation and Finale (5:59)

Total Running Time - 64:25 (according to back cover) or 64:13 (according to cd player)

Several different versions of this bootleg exist. Despite how its cover claims it's the complete score from the original master tapes, the one whose tracks are listed above appears to be simply a fan's homemade copy from the Alien: 20th Anniversary Edition DVD (all its cues are straight from the movie). The one listed below is most likely the "real" bootleg. It has the same cover as the fan one along with another that was taken from an early promotional poster for the film. The last bootleg seems pretty close to the Complete Edition except the tracks are labeled differently, and there are a few extra cues like the music from the Aliens ride.

1. Main Title - The Nostromo (4:03)
2. Main Title (Alternate) (4:07)
3. Hypersleep (2:38)
4. Hypersleep (Alternate) (2:20)
5. The Landing (4:25)
6. Derelict (1:43)
7. The Jockey (2:22)
8. The Jockey (Alternate 1) (2:26)
9. The Jockey (Alternate 2) (2:22)
10. The Egg Chamber (2:17)
11. Acid Test (3:02)
12. Acid Test (Alternate) (3:02)
13. Studies (0:59)
14. Ejecting Kane's Body (1:24)
15. Search - Brett's Demise (2:05)
16. The Droid (3:22)
17. Parker's and Lambert's Demises (1:46)
18. The Corridor (1:01)
19. "I got you!" (1:52)
20. The Shuttle (3:05)
21. The Shuttle (Alternate) (3:01)
22. Breakaway (1:25)
23. Breakaway (Alternate) (3:08)
24. End Titles (Unused) (3:00)
25. "Rise and shine Lambert!" (0:59)
26. --- (2:20)
27. --- (1:29)
28. --- (1:00)
29. --- (1:02)
30. The Shaft Part 1 (1:31)
31. The Shaft Part 2 (2:31)
32. "Signing off." (1:51)

Total Running Time - 74:05

Disc 1

Composer's Cut
1. Main Title (4:08)
2. Early to Rise (2:42)
3. Rough Landing (4:28)
4. Walking Distance (4:29)
5. Dead a Long Time (4:28)
6. Eggs or Something (2:35)
7. A Wonderful Defense Mechanism (3:35)
8. In the Lab (1:01)
9. Missing a Guest (0:54)
10. Taking Off (4:28)
11. Last Supper (1:46)
12. Seek and Destroy (0:59)
13. Here Kitty (2:04)
14. Does Not Compute (1:26)
15. No Blood, No Dallas (4:25)
16. A Confrontation with Ash (3:25)
17. Scared Stiff (1:46)
18. Destruct System Activated (3:23)
19. T Minus Thirty Seconds (1:52)
20. The Stowaway (3:02)
21. The Last Survivors (2:59)
22. End Credits (2:57)

Director's Cut
23. Main Title (4:09)
24. Early to Rise (2:43)
25. Walking Distance (0:10)
26. Dead a Long Time (3:21)
27. Eggs or Something (0:57)
28. A Wonderful Defense Mechanism (4:31)
29. A Little Night Music (1:17)
30. Scared Stiff (1:17)

Disc 2

Director's Cut +
1. No Blood, No Dallas (4:41)
2. The Stowaway (3:08)
3. The Last Survivors (3:01)
4. Symphony No. 2 "Romantic" (2:48)

Album Cues
5. Main Title (3:31)
6. The Face Hugger (2:32)
7. Breakaway (3:00)
8. Acid Test (4:35)
9. The Landing (4:28)
10. The Droid (4:41)
11. The Recovery (2:44)
12. The Alien Planet (2:27)
13. The Shaft (3:57)
14. End Credits (3:01)

Bonus Tracks
15. Main Title (3:17)
16. Hyper Sleep (2:51)
17. The Landing (4:25)
18. Breakaway (3:15)
19. The Droid (3:44)
20. The Door (1:27)
21. End Credits (3:11)
22. A Little Night Music (0:52)
23. Symphony No. 2 "Romantic" (2:38)
24. The Nostromo (1:00)
25. ALIENS - The Ride (6:29)

Spanish Bootleg

Disc 1

1. 20th Century Fox Theme (0:11)
2. Main Title - The Nostromo (4:08)
3. Hypersleep (2:43)
4. The Landing (4:28)
5. The Derelict (2:01)
6. The Jockey (2:22)
7. The Egg Chamber (2:19)
8. Face Hugger (3:04)
9. Main Title (from "Freud") (3:17)
10. Studies (1:01)
11. Serenata No. 13 "Eine Kleine Nachtmusik" (3:48)
12. Ejecting Kane's Body (1:47)
13. Search (0:59)
14. Brett's Demise (0:52)
15. Charcot's Show (from "Freud") (5:07)
16. Desperate Case (from "Freud") (3:29)
17. Search (Alternate) (1:13)
18. The Droid Part 2 (1:13)
19. The First Step (from "Freud") (2:10)
20. Parker's and Lambert's Demise (1:47)
21. The Corridor (1:02)
22. "I got you!" (1:54)
23. The Shuttle (3:08)
24. Breakaway (1:26)
25. Symphony No. 2 "The Romantic" (2:47)

Disc 2 - The Rejected Themes

1. Main Title - The Nostromo (Alternate) (4:09)
2. Hypersleep (Alternate) (2:44)
3. Derelict (Alternate) (1:42)
4. The Jockey (Alternate 1) (2:27)
5. The Jockey (Alternate 2) (2:25)
6. The Egg Chamber (Alternate) (2:05)
7. The Egg (0:57)
8. The Egg (Alternate) (1:30)
9. Back to the Nostromo (1:02)
10. Face Hugger (Alternate) (3:03)
11. Acid Test (0:33)
12. Looking for the Face Hugger (0:53)
13. The Shaft Part 1 (1:51)
14. The Shaft Part 2 (2:32)
15. The Droid Part 1 (2:12)
16. Detonation Sequence (2:20)
17. The Shuttle (Alternate) (3:02)
18. Breakaway - "Signing Off" (Alternate) (3:08)
19. "Signing Off" (1:41)
20. End Titles (Alternate) (3:01)
21. The Alien Suite (Bonus Track) (5:23)

Total Running Time - 1:46:56

Alien Trilogy CD

Alien
1. Main Title (3:16)
2. Hyper Sleep (2:45)
3. The Landing (4:33)
4. Breakaway (3:11)
5. The Droid (3:46)
6. The Door (1:28)
7. End Title (3:27)

Aliens
8. Main Title (6:21)
9. Futile Escape (5:45)
10. Bishop's Countdown (3:21)

Alien 3
11. Lento (5:23)
12. Candles in the Wind (4:16)
13. Adagio (4:15)

Total Running Time - 51:47

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