Collision Course
Who is Arra? She is old - older than Earth itself - with a beauty that only age can bring. Commander Koenig's encounter with her is also an encounter with destiny. It all happens when the Moon is on a collision course with a planet many times its size... ITC summary
- Final shooting script 9th August 1974, updated final shooting script 13th August 1974
- Filmed 27th August- 6 September 1974
- Edited into the 1982 compilation movie Journey Through The Black Sun
- This was Margaret Leighton's final screen performance. Keith Wilson:
She was wonderful, but she didn't understand a word she was saying. She had a lot of nonsense to say and hadn't a clue what it meant. She was really quite worried about it.
. Ray Austin: Margaret's a friend of mine. She knew she was dying. I shot, I think, 15 pages in two days with her, which was unheard of. 'You'd better get this shot, because I'm not going to last long...' she said near the end of shooting. She couldn't move, we had to put her in a wheelchair.
- The third episode Martin Bower worked on. He contributed the massive Arra shuttle (designed by Brian Johnson) and the Alphan mines in two scales, and a tiny 14cm Eagle. The shuttle is 1.8m long and was carved from solid wood in ten days. The wings are plywood. The mines were made from plastic picnic dishes bought from Woolworths. In the script the shuttle is described as a wingless vulture, like a Concorde with giant jet intakes.
- The shuttle appears in the spaceship graveyard in Dragon's Domain. Both shuttle and mines reappear in the spaceship graveyard in The Metamorph.
- Arra's ship model photos
- Alpha mines model photos
- SFX storyboards
- Library Special Effects
Library tracks:
- track from Joe 90 "Arctic Adventure" by Barry Gray
- track from Joe 90 "Operation McClaine" by Barry Gray
- track from Thunderbird 6 by Barry Gray
- ITC Music Cue Sheet
- If the planet is 34 times lunar mass, it is less than half the mass of Earth (about the size of Mars); by diameter it would be a little less than Saturn. In the latter case much of the bulk would be gaseous and the air would not be breathable.
- In 2022, NASA's DART mission succeeded in altering the course of the asteroid Dimorphos by crashing a spaceship into it.
- Shockwaves cannot travel through the vacuum of space. Destroying an asteroid on a collision course won't help much, as it just turns it into debris. Debris and radiation can travel through a vacuum; either could in turn alter the moon's course with sufficient energy and mass. Detonating nuclear explosives above the surface of an asteroid or the Moon (at an optimum "stand-off" height) can be preferable to detonating it on the surface or subsurface, because it won't break up the asteroid into dangerous debris. The radiation from the explosion vaporises the surface rock; the vaporised ejecta acts like a rocket engine, changing the course of the asteroid. The Moon's course is also altered in Seance Spectre.
- The mines hang on cables under the Eagles. The asteroid must have enough mass to have gravity. But the mines are also below the Eagles in space, where there is no gravity. They should be being towed behind the Eagle.
0 fatalities.
Alpha Technology:
- Orbital satellites are mentioned. This is the only time they are referred to, although a Command Centre panel is Year Two is labelled "Satellites" (shown here). Unlike Alpha, they are not damaged by the explosion (they may have been shielded by the moon itself).
- "Interstellar communications" are referred to. It is not affected by intense radiation. Not all Eagles are equipped with it. "Interstellar strength" communication is also referred to in Space Brain and Death's Other Dominion
- The multi-function hatch is shown; here it arms and detonates the nuclear charges.
- The countdown clock is shown.
- There is a Command Conference
Eagle 1 (Alan); 4 (Rescue); 10 (bomb, no pod); 11,12,29 (named)
- Although the Eagles dock, we do not see a docking tube as in Earthbound and Guardian Of Piri. When they land, there seems to be no physical connection between the two ships.
- We see the Rescue pod. Unlike previous appearances, the 44 inch Eagle has stripes that don't reach the base of the pod (they do in shots of the 22 inch Eagle).
- Eagle 1 is badly damaged.
- It is not clear how the mine cable is connected to the Eagle. We see it attached to both a podless Eagle and a normal transporter pod. It is likely Carter's Eagle has a pod because the story required it would dock to Koenig's rescue Eagle later - it would not be possible without a pod.
Atheria. Note ITC publicity often named it Aestheria. This is wrong.
Aliens:
Queen Arra. Humanoid.
Props:
The fires in Main Mission are actually beyond the edge of the desks.
"This Episode" contains several scenes not in the episode. Among the unused footage is a shot of Sandra knocking over her coffee mug.
- A suspenseful story; the themes of faith and destiny are strongly made. Like Black Sun a "mysterious unknown force" saves the Alphans.
- The early scenes of Koenig's loyalty to Alan are heavy-handed and overacted. In no other episode is Koenig so committed to Alan.
- Helena does not appear until 15 minutes into the episode. The story features the supporting cast (Alan, Paul, Sandra, Kano) more than usual.
- In 1979 the TV series Tomorrow People used footage of Arra's shuttle representing a Nasa shuttle (episode War Of The Empires).
- The A&E Bonus Disc contains an alternate edited version of one scene, the final section of Arra and Koenig in the Spaceship Chamber. The sequence is almost identical apart from the omission of one line of dialogue. Koenig asks what she is going to do. In this version, she disappears without the line "I go to shape the future of eternity. And I need your help." (it is heard in voice over after Koenig walks away).
External Links
Episode Guide 
Year 1 - Episode 13 
