Questions tagged [laser]
Questions regarding devices which emit focused beams of electromagnetic energy.
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What are these structures on the Lunar Ranging Retro Reflector (LRRR) arrays for?
In Local expansion measured, near zero via Lunar Ranging - what about deep space probes? I used images of the retro-reflector arrays that were left on the moon by Apollo 11, 14, and 15. The Lunar ...
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Is it possible to extend high speed data transmission with lasers to the distance Earth to Mars?
Data transmission using an optical laser between ground station and a GEO satellite may offer very high data rates, up to 1.8 GBit/s for instance.
But what about a transmission from Earth to Mars ...
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Receiver and transmitter in RF/optic satellite communication: distance vs data rate v2
The first version of this question is here.
I have read the article "Optical communications work best over relatively short distances in space." by Toyoshima, M., Leeb, W., Kunimori, H. and ...
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Why is the Aeolus space laser losing power so quickly?
The BBC News article Aeolus: Wind-mapping space laser is losing power says that
Europe's Aeolus satellite was launched last year to gather data to improve weather forecasts, and its observations have ...
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How does QUESS, China's quantum communications satellite experiment, relay entangled signals?
China launched the Quantum Experiments at Space Scale (QUESS) on the satellite called MOZI or Micius today, which will be used for quantum communications between China and Europe. Popular Science ...
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How many (presumably friendly) lasers are being shot at us from space? (pew! pew!)
Example: at first they could not decide which of the green laser-shooting satellites was responsible! Too many to choose from?
See Science Alert's February 9, 2023, Ominous Green Lasers Shot Over ...
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How did LADEE and LDRC measure it's distance from Lunar orbit to Earth to 1 centimeter accuracy using optical communications?
The video Donald Cornwell plenary talk: NASA's Optical Communications Program: 2015 and Beyond was presented at SPIE Photonics West 2015. It's a great talk and worth the time.
LADEE had [the Laser ...
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Why does LRO's laser altimeter telescopes use lenses instead of mirrors?
From Space.com's NASA's Piggyback Experiment on Israeli Moon Lander Could Aid Future Lunar Touchdowns shows an image of the laser altimeter on the LRO. It looks like the "transmit" and "...
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What's the current timeline for NASA's Mars orbiter laser communications?
Dr. Jim Green, Director, NASA Planetary Science Division, mentioned during his "The Martian": Science Fiction & Science Fact talk for the 18th Annual International Mars Society Convention (you can ...
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How much power loss does the LLCD suffer in transit?
Space.com writes to say (freeform improved quote):
The LLCD (Lunar Laser Communication Demonstration) space terminal is designed to beam data from the moon at a rate six times faster than the best ...
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Breakthrough Starshot's 100 Gigawatt laser array - what's the current thinking how this might work?
In the article Breakthrough Starshot tricks out massive telescope for planet hunting there is casual mention of a "phased array of lasers in the 100GW range" that will propel a gram scale spacecraft ...
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How accurate can near earth asteroids be tracked?
To get more statistical significance for the suspected flyby-anomaly (or to refute it), it would be desirable to track as many hyperbolic earth flybys to within 1mm/s as we can get. Can we track ...
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When they shoot lasers at the Moon for ranging, what is the shape of the beam?
Laser ranging of the Moon is usually done with a Q-switched pulsed laser fed into a big (1 or 2 meter diameter) telescope as a collimator in order to get a tight beam all the way to the Moon in hopes ...
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Is pinging the Moon with a laser as shown on "The Big Bang Theory" possible?
In an episode of season 3 of The Big Bang Theory, the cast sends a laser pulse to the Moon. This seems to be a real thing: What Neil & Buzz left on the Moon (2004). My questions are:
Could ...
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Laser propulsion possible?
Is it possible to get an impulse, if you shoot at a solar sails with lasers mounted on the spaceship?
If so, why doesn't a laser create a force, if it fires/releases a photon?
Is the impulse ...
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