Questions tagged [laser]

Questions regarding devices which emit focused beams of electromagnetic energy.

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Example of an optical phase locked loop (PLL) used (or planned for) free space optical satellite communication

I am looking for examples of an optical phase locked loop (OPLL) used (or planned for) free space optical satellite communication. I have found one, but in the block scheme there is a photodetector (...
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64 views

Frequency/Spectrum regulation document for laser communication

For RF we have the frequency allocation table, where the RF spectrum is regulated. Optical has big bandwidth, there is a lot of frequency space. How do we regulate optical spectrum? I didnt find any ...
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Receiver and transmitter in RF/optic satelite communciation: distance vs datarate.v 2

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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219 views

Have "space lasers" really been used to temporarily blind US satellites?

In CNN's video An exclusive look into how Space Force is defending America they talk with Gen. John W. Raymond, Chief of Space Operations, US Space Force. After about ...
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160 views

Small probes to Alpha Centauri powered by light sails with a journey time of 20 years

This news item states that scientists have potentially devised a way to send a number of small probes to Alpha Centauri at quarter the speed of light. The journey would take 20 years and each small ...
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Did Perseverance get an experimental optical communications terminal?

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. Near the end at about <...
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1answer
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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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154 views

Using lasers to reach the Karman line

I've just seen this Anton Petrov video: New Type of Laser Levitation Could Help Us Explore the Mesosphere. It's about this new form of levitation that uses lasers to heat up the air underneath a craft,...
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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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Why don't lasers last long in space?

A news article reports that OSIRIS-REx was equipped with two lasers for the spacecraft to shoot off the rock and study the echo to facilitate its landing and sampling maneuver. ... Most lasers don't ...
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How could METI laser pulses be "brighter than the Sun"?

This Astronomy online course page The Search for Extraterrestrial Intelligence contains the following, about half-way down: However, in recent years, human engineers have learned how to make flashes ...
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Does Falcon 9's first stage use laser, radar or vision to assist landing? [duplicate]

Does Falcon 9's first stage use only GPS when it makes its vertical precision landing, or is it assisted also by radar or laser ranging or computer vision? If not, why not?
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How many (presumably friendly) lasers are being shot at us from space? (pew! pew!)

A comment below @A.Rumlin's answer to Is there any spacecraft that is ping-able? links to a Facebook page (in Russian) which shows an astrophotographer's photograph of stars plus a big green flare ...
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127 views

Would an incandescent light bulb be more efficient than a laser for photon propulsion?

In an incandescent light bulb pretty much almost all of the input power is radiated as photons. While perhaps 10% of the power is useful for human vision and the rest are longer wavelengths, it's all ...
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Do the latest Starlink satellites use inter-satellite laser communications?

Do the latest (as of Jan 30, 2020) Starlink satellites use inter-satellite laser communications? I can't find any info about that!
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Is it recorded and/or documented when and where Curiosity's ChemCam's laser has zapped on Mars?

The article with the title "NASA Rover's Images Show Laser Flash on Martian Rock" tells us that the ChemCam's laser had zapped more than 600 rock and soil targets on Mars since Curiosity landed in ...
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185 views

What exactly is a "Next Generation Lunar Reflector"? Difference in design and performance?

Space.com's 50 Years After Apollo, India Is Carrying a NASA Laser Reflector to the Moon (And It's Only the Start) is a little confusing because it talks about three retroreflectors: - Apollo era ...
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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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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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Laser powered LEO launch system

Latest research on beam powered propulsion seem to focus on the microwave spectrum as it is easy to catch by the orbital vehicle. However I argue it could be way cheaper to use a solar powered laser ...
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Was any data actually transmitted between OSCD and ISARA in the recent CubeSat lasercom test?

Two CubeSats (the OCSD and ISARA CubeSats) recently demonstrated technology for on-orbit sat-sat laser communications. All the information I have been able to find doesn't indicate if the test ...
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How to get an initial setting of the range gate for a Lunar Laser Ranging using a new Retro Reflector for the first time?

From an answer to this question They were searching by aiming their laser at the moon and looking for reflections. But the system is set to only detect photons in a very narrow range of ...
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Could outer system probes detect lasers shone at them from earth (orbit)?

Does the Voyager spacecraft have instruments capable of detecting laser light if shone at them? New Horizons certainly does. Any other probes? Is there any laser capable of accuracy and power enough ...
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Could we use a narrow paradigm, say laser, to get info faster from New Horizons? (With a moon base.)

There was just a question (actually, on Astronomy) about why the data rate from New Horizons is low. Of course, even with the most directional radio antennas, the spread is enormous. I guess ...
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Could a laser ablation-based propulsion system really accelerate an object to 0.001 c?

Comments below this answer suggests that a laser ablation-based propulsion system, where the laser is separate from the object to be accelerated, could accelerate an object to about 1/1000 of the ...
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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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How would a laser "shoot down" space junk?

This question links to an article describing a ground-based laser designed for shooting down orbiting space debris: "The scientists intend to use the massive soon-to-be-built telescope at the Altay ...
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96 views

Feasible to use lasers / concentrated light to power solar cells in our solar system?

I was watching a video on Youtube which criticized Elon Musk's idea to use solar power to power the space craft at long distances from the sun such as Saturn. That got me thinking whether it would be ...
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191 views

Laser communication for interplanetary probes - aiming is impossible without beacon?

Laser communications are considered very promising for interplanetary probes because of potentially much higher data rates. I found that laser communication at large distances (over 3 a.u. ~ 450 ...
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317 views

Attitude requirements for inter-satellite laser communication

Previous questions have address the beam divergence angles and the expected signal attenuation for laser communication between spacecraft. However, I was wondering what is a typical receiver aperture ...
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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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Could the moons of Jupiter or Saturn be heated to human-friendly temperatures?

I always loved the part in 2001 where Jupiter becomes as star. Has anyone ever suggested placing power generating stations high in the atmosphere of gas giants, and beaming the energy to colonies on ...
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Would laser and beamed energy anti satellite weapons cause much space debris?

Laser and other beamed energy weapons, in orbit or from Earth, could potentially make their targets malfunction from overheating and perhaps even partial melting. Would this be a way of space warfare ...
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Why would "Breakthrough Starshot" need photon thrusters?

Found here (italics added, bold in source): Nanocrafts are gram-scale robotic spacecrafts comprising two main parts: StarChip: Moore’s law has allowed a dramatic decrease in the size of ...
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Is it possible for small satellites to orbit in MEO or GEO?

I am researching satellite technology, and in particular I am looking at the rise and implications of smallsat technology. As far as I know, there are currently no satellites beyond LEO that would be ...
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258 views

A laser can propel a spacecraft to 20% of light speed, time shorter on spacecraft?

So I recently learned about a project about using lasers on Earth to propel a spacecraft to 20% of light speed for interstellar traveling. So this brings an interesting question, how much shorter ...
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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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Deorbit LEO debris with a higher orbit laser?

A couple of days ago I asked Can a laser be used to clear the launch path of a rocket? turns out this is not a good plan but the answer by Hobbes suggests the idea of clearing debris with a laser is ...
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Can a laser be used to clear the launch path of a rocket?

Military grade lasers shooting down incoming missiles have been in the news since Ronald Reagan was the US president. The problems, as I recall are mostly about diffusion in atmosphere. The Kessler ...
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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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665 views

Characteristics of the inter-satellite optical link

I'm currently diving into this topic and as I understand from the brief search there are two main types of inter-satellite link: radio and optical. As I can see, one of the main distinction of optical ...
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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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Are we actually that close to techniques of accelerating probes to speeds like a quarter $c$?

As recent research has been started by a team around Stephen Hawking under the name Breakthrough Starshot they are going for accelerating little probes up to 0.2~0.25$c$. There isn't that much ...
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331 views

Can you launch a probe to the Moon using a laser propelled craft?

Take a very light object, propel it with a laser source on Earth at a constant acceleration. Can this object reach the Moon? Could this be more reliable than a rocket? (supposing solar panel 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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laser propulsion from a lagrange point? [closed]

Simply put, would it make sense to place laser in space to propel a solar sail? Thinking about solar sails, and the inefficiencies of sending a laser through the atmosphere, I wondered if it made ...
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Does any satellite communicate only through laser?

I have read (here) and heard (on astronomy podcast) that radio waves decay or are indistinguishable the more distance they travel. Do any of man made satellites communicate with Earth solely by ...
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Doing an experiment to point a laser to the moon and back

After reading this question: I got an itch to to test out the mirrors myself (and maybe record whole process to irritate conspiracy nuts). What equipment would I need? I assume a high powered laser ...
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448 views

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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Can't we use laser transmitters instead of large radio dishes on deep space probes?

Isn't it possible to use a laser as an "antenna" that transmits data? This would save quite a lot of mass since you don't need a large dish. The only problem I can think of is how would you modulate ...