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Questions tagged [optical]

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What optical design is used by the GEDI's receiving telescope and how is the secondary held in place?

GEDI is a sophisticated LIDAR instrument now on its way to the ISS. Once installed, it will use powerful laser pulses (10 mJ, 242 Hz) from several lasers to map height in 3D, collecting multiple ...
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How does the thin gold film in the glass of spacesuit helmets block thermal IR but transmit visible? What's the property?

Comments below this answer suggest that there is a thin gold coating on the glass of spacesuit helmets that blocks thermal IR (say roughly about 10 to 30 microns) but is mostly transparent to visible ...
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What would be the equivalent camera performance specification of Earth-imaging satellites, compared to consumer DLSRs?

In order to better understand what Earth imaging cameras are like (as seen in Google Earth) from the point of view of a photographer, I've asked the following. Consumer-grade cameras like DSLRs, ...
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Are there plans or a program for an optical relay pathfinder for deep space?

In Glenn Research Center's Richard Reinhart's slides Space Communication and Navigation TestbedCommunications Technology for Exploration for the 2013 ISS Research and Development Conference I saw an ...
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Yet another OSIRIS! Has the DLR/GOM Space test of the cubesat optical communications link happened yet?

Speaking of "all things OSIRIS" I just ran across the OSIRIS optical communications system for cubesats and smallsats. OSIRIS (Optical Space Infrared Downlink System) highly compact optical ...
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2answers
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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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Why do the LAGEOS' satellites have four germanium corner cube reflectors out of over 400?

When I was writing this answer about the LAGEOS satellites, I noticed that only four of the over four hundred corner reflectors are made of optical germanium rather than fused silica. Fused silica (...
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What GEO relay satellite will the ISS use for end-to-end optical communication with a ground station?

This LEMNOS page on NASA's Explorations and Space Communications site says: The Integrated Laser Communication Relay Demonstration (LCRD) Low-Earth Orbit (LEO) User Modem and Amplifier Terminal (...
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Could multimode (polymer) optical fiber Gigabit Ethernet be a better choice than WiFi inside future satellites?

In this answer the recent question Are and should satellites use wireless communication internally, rather than cables? it is stated that: This is actually an open research area and despite ...
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Have amateur satellites ever experimented with optical communications?

I meant to include the more recent amateur satellites such as cubesats, and also amateur radio satellites - where the heritage of amateur satellite building (mostly) has its roots. Have amateur ...
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All Optical Global Network - how does the space-to-ground link avoid clouds?

I just saw the news item in Lightwave's online website: Laser Light to leverage free-space optics in space for Optical Satellite as a Service. All Optical Hybrid Global Network (or HALO, as laser ...
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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 is long-distance optical communications coming along in space?

I remember there was a test of optical communication and some data transfer from lunar orbit to earth, and I think the ISS uploaded (or downloaded-up? which is correct here?) a movie from earth. In ...
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How could the laser from Earth to a spacecraft be used other than to propel its light sail?

The Starshot Breakthrough Initiative, sponsored by Yuri Milner, now finances the attempt to use a huge laser on Earth to propell a tiny spacecraft to huge velocity. Not having to carry the energy for ...
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Would plasma sheathes from reentry heating block optical/UV communications as well as radio?

During reentry, it's routine for the ionized atmosphere surrounding the spacecraft to cut off radio communications for a certain period. As far as I know, this can't be avoided, except perhaps by ...
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What are the “crossing beams of light” in the Cassini images taken during Enceladus plume flyby?

Whilst checking the latest images of the E-21 flyby returned by the Cassini probe, I've noticed that some of them show interesting optical phenomena that I'm not sure I can explain; For example, on ...
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Accumulated environmental damage to Hubble main mirror

I'm interested in understanding what effect does long-term radiation and microdust exposure would do to the surface roughness of a high-precision mirror like the one on the Hubble. Since it has been ...
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Is photography from a satellite good enough to make out a person on the ground?

When I first saw Google Maps satellite view many years ago, I remember being greatly impressed (and somewhat surprised) with the image quality, considering the photographs came from up there in space. ...
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Was Hubble really related to spy satellites?

Around the launch of the Hubble Space Telescope, I remember comments in the media that the Hubble may be related to certain espionage satellites. The Hubble was designed and built around the time that ...
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278 views

What will the new Iranian satellites be imaging?

Iran is soon to launch two satellites which will reportedly take images "with a high degree of accuracy of less than 10 meters" (azernews). What will these satellites be imaging?
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Long range laser communication beam divergence angle values?

NASA has been working on demonstrations of laser communication with satellites. The motivation is simple, in that lasers see less power loss because they spread over a smaller angle. That raises the ...
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Can you have a rainbow on any bodies in the solar system besides Earth?

We know from Flying on dense atmosphere planets & moons that many bodies in our solar system have sufficient atmosphere for at least the concept of flying to be considered. What about the ...