Questions tagged [laser]
Questions regarding devices which emit focused beams of electromagnetic energy.
64
questions
7
votes
2
answers
150
views
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 ...
- 191
15
votes
2
answers
2k
views
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 ...
- 17.7k
5
votes
1
answer
237
views
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 (...
2
votes
1
answer
245
views
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 ...
- 149k
3
votes
1
answer
121
views
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 ...
- 51
2
votes
1
answer
132
views
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 ...
- 125
4
votes
2
answers
391
views
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....
- 125
0
votes
1
answer
137
views
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 ...
- 267
1
vote
1
answer
209
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 ...
- 71
1
vote
1
answer
360
views
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 ...
- 71
1
vote
1
answer
621
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 ...
- 149k
3
votes
1
answer
225
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 ...
- 13k
2
votes
1
answer
83
views
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 <...
- 149k
3
votes
1
answer
100
views
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 ...
- 149k
5
votes
2
answers
212
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,...
- 812
2
votes
1
answer
175
views
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 ...
- 149k
30
votes
1
answer
7k
views
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 ...
- 11.5k
2
votes
0
answers
78
views
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 ...
- 149k
2
votes
1
answer
255
views
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?
- 26.9k
5
votes
1
answer
424
views
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 ...
- 149k
1
vote
1
answer
155
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 ...
- 149k
8
votes
1
answer
2k
views
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!
3
votes
1
answer
66
views
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 ...
- 7,493
1
vote
1
answer
228
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 ...
- 149k
1
vote
1
answer
177
views
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 "...
- 149k
9
votes
1
answer
452
views
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 ...
- 149k
3
votes
0
answers
102
views
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 ...
- 81
1
vote
0
answers
52
views
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 ...
- 1,700
3
votes
2
answers
158
views
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 ...
- 48.8k
1
vote
0
answers
76
views
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 ...
- 431
14
votes
5
answers
4k
views
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 ...
- 1,614
0
votes
1
answer
112
views
Achieving relativistic speeds with the use of lasers
Basic data about our spacecraft:
Basically, were using a laser as an engine.
Mass: 1000 tons.
Electrical power for the laser: 10 GW.
Efficiency of the laser(s) : 50%.
So first I calculated the ...
- 9
4
votes
1
answer
213
views
Could a laser ablation-based propulsion system really accelerate an object to 0.001 c?
Comments below this answer suggest that a laser ablation-based propulsion system, where the laser is separate from the object to be accelerated, could accelerate an object to about $\frac{1}{1000}$ of ...
- 149k
42
votes
3
answers
13k
views
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 ...
- 815
8
votes
3
answers
498
views
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 ...
- 181
4
votes
1
answer
107
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 ...
- 201
7
votes
1
answer
245
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 ...
- 9,041
5
votes
1
answer
445
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 ...
- 6,200
11
votes
3
answers
576
views
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 ...
- 48.8k
1
vote
0
answers
107
views
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 ...
- 221
4
votes
2
answers
209
views
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 ...
- 26.9k
3
votes
0
answers
224
views
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 ...
- 4,218
2
votes
2
answers
1k
views
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 ...
2
votes
1
answer
324
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 ...
- 331
5
votes
0
answers
748
views
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 ...
- 149k
4
votes
1
answer
446
views
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 ...
- 27.1k
1
vote
1
answer
270
views
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 ...
- 27.1k
4
votes
1
answer
325
views
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 ...
- 1,375
3
votes
2
answers
745
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 ...
- 153
11
votes
1
answer
2k
views
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 ...
- 23.8k