Comments on: Laser propulsion https://habitablezone.com/2016/02/19/laser-propulsion/ Fri, 03 Apr 2026 18:20:54 -0700 hourly 1 http://wordpress.org/?v=3.3.1 By: ER https://habitablezone.com/2016/02/19/laser-propulsion/#comment-35707 ER Sat, 20 Feb 2016 19:05:45 +0000 https://www.habitablezone.com/?p=55866#comment-35707 Especially if the vehicle is a long way off, because of light-travel time. If the vehicle started to drift off the beam, by the time the information got back to the laser operators, and the beam was re-directed, the vehicle would have drifted even further. You can't get any information back from the vehicle faster than light, and then you have to multiply that by two to get the corrected beam back to the spacecraft. Especially if the vehicle is a long way off, because of light-travel time. If the vehicle started to drift off the beam, by the time the information got back to the laser operators, and the beam was re-directed, the vehicle would have drifted even further.

You can’t get any information back from the vehicle faster than light, and then you have to multiply that by two to get the corrected beam back to the spacecraft.

]]> By: RL https://habitablezone.com/2016/02/19/laser-propulsion/#comment-35702 RL Sat, 20 Feb 2016 16:16:45 +0000 https://www.habitablezone.com/?p=55866#comment-35702 Though the reflected light from the sail could be used as a beacon so the pointing could be adjusted... like the way beacons are used in laser communication. Another problem would be how to keep your transmitter in a stable orbit, since it will be propelling itself as it beams the energy out... Look at the different scenarios at the end of the paper on pgs 33-34... They give an idea of the time you need to stay on target... Though the reflected light from the sail could be used as a beacon so the pointing could be adjusted… like the way beacons are used in laser communication.

Another problem would be how to keep your transmitter in a stable orbit, since it will be propelling itself as it beams the energy out…

Look at the different scenarios at the end of the paper on pgs 33-34…

They give an idea of the time you need to stay on target…

]]> By: ER https://habitablezone.com/2016/02/19/laser-propulsion/#comment-35701 ER Sat, 20 Feb 2016 14:35:10 +0000 https://www.habitablezone.com/?p=55866#comment-35701 Its a tiny target, very far away, with a constantly changing component of motion perpendicular to the line of sight because the laser platform itself is moving and accelerating in very complex ways. Perhaps this is addressed in the paper, but I must confess I got lost, I couldn't follow the math. Its a tiny target, very far away, with a constantly changing component of motion perpendicular to the line of sight because the laser platform itself is moving and accelerating in very complex ways. Perhaps this is addressed in the paper, but I must confess I got lost, I couldn’t follow the math.

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