Questions tagged [laser]
Questions regarding devices which emit focused beams of electromagnetic energy.
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Would a laser seismometer work from lunar orbit?
Lasers today have become extremely sensible, they can detect sub-millimeter movements of a surface from a distance. Could this feature be exploited to create a lunar seismometer working from a probe ...
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How do the interferometers on the drag-free satellite LISA receive power without altering their geodesic trajectory?
LISA is a proposed space probe designed to measure gravitational waves. It aims to measure gravitational waves directly by using laser interferometry. It uses a drag-free satellite design to protect ...
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Deep Space Optical Communications (DSOC) - from what distance could a flashlight be detected by a space-based telescope
Flight laser transmitter - for Psyche mission has Mass 29 kg (100 W).
It also requires pointing up to 3 degrees of the Sun (towards the receiver telescope).
My question is about really small probes (...
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Has anyone in space beyond LEO seen or has anything photographed a non-pointer laser from Earth?
The two current answers to Has anyone in space seen or photographed a simple laser pointer from Earth? both describe small, low power lasers from Earth aimed towards the ISS in LEO.
Here I'd like to ...
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Precise Orbit Determination (POD) vs GNSS accuracy; seeking references
Precise orbit determination provides performances that are not currently achievable with GNSS systems. I cannot find information of the reason for this. I imagine different possibilities:
Use of ...
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Transmit power for low/high wavelength [closed]
I am reading the book: Kaushal, H., Jain, V.K. and Kar, S., 2017. Free space optical communication. New Delhi: Springer India.
I have asked before about a reason of choice of wavelength for beacon ...
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What are the reasons for the specific operating wavelengths chosen for laser communication?
I am reading the book: Kaushal, H., Jain, V.K. and Kar, S., 2017, Free space optical communication, New Delhi: Springer India.
The operating wavelengths for beacon and data transmission were discussed....
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Beacon (PAT) in optical free space communication [closed]
Nanosatellite Optical Downlink Experiment (NODE) mission has 3 "signal":downlink, beacon uplink and RF.
According to a description of the mission, the high-rate downlink and beacon uplink ...
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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 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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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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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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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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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!)
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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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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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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