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# Margaret The Space Witch #


2643 × 3060 px - 6.4 MB PNG.

Accountant and bookkeeper in the Coven of '68 on Wineland II

Go to katharsisdrill.art





Image/Photo

Like all other works published on the Katharsisdrill website this work is licensed under a

Creative Commons Attribution 4.0 International License.


Attribute: Katharsisdrill - Link to: https://katharsisdrill.art



Made with Krita

#art #Krita #Gimp #drawing #Illustration #witch #wikka #divination #space #scifi #red #planet #Margaret
#mywork #ownwork #cc #creativecommons #cc-by
 
I just found out that @Winchell Chung (Atomic Rockets) is in the hospital with a terminal prognosis. I can't say what I'm feeling, so I'm just passing it along for those who don't already know.

#SF #ScienceFiction #OGRE #Space #SpaceTechnology
 
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# Arkariater #


4734 × 2819 px - 11.2 MB PNG.

Are you in doubt... in doubt if you should sell the car and move into an eco-flat in Brighton, or maybe refurbish the kitchen and move from Fred?

Well the solution to your problem is to seek advice at the Arkariater. 3 years warranty on any advice!

Go to katharsisdrill.art





Image/Photo

Like all other works published on the Katharsisdrill website this work is licensed under a

Creative Commons Attribution 4.0 International License.


Attribute: Katharsisdrill - Link to: https://katharsisdrill.art



Made with Krita

#art #Krita #Gimp #drawing #Illustration #norn #fortunetelling #Arkariater #divination #space #scifi
#mywork #ownwork #cc #creativecommons #cc-by
 

Planet Aqua: Solutions from Space for Clean Water






Video: 00:51:12

Water is life, on Earth and in space. Dutch ESA astronaut André Kuipers recounts his experience living in space for 204 days, and his time looking back on the blue face of ‘Planet Aqua’, comparing notes with divers about what is going on beneath the waves. He goes on to explore how space technology is being used for water management, from orbital tracking of water quality and pollution to spacecraft-grade recycling systems deployed down on the ground, as well as ambitious efforts to identify marine plastic litter using satellites. Produced for SIWI World Water Week with the support of the Netherlands Ministry of Foreign Affairs.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

Planet Aqua: Solutions from Space for Clean Water






Video: 00:51:12

Water is life, on Earth and in space. Dutch ESA astronaut André Kuipers recounts his experience living in space for 204 days, and his time looking back on the blue face of ‘Planet Aqua’, comparing notes with divers about what is going on beneath the waves. He goes on to explore how space technology is being used for water management, from orbital tracking of water quality and pollution to spacecraft-grade recycling systems deployed down on the ground, as well as ambitious efforts to identify marine plastic litter using satellites. Produced for SIWI World Water Week with the support of the Netherlands Ministry of Foreign Affairs.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

A-74 iceberg near collision with Brunt Ice Shelf






Image: New radar images show the A-74 iceberg spinning around the western tip of the Brunt Ice Shelf, brushing slightly against it before continuing southwards.

#earth #science #space #esa #europeanspaceagency
posted by pod_feeder_v2
 

A-74 iceberg near collision with Brunt Ice Shelf






Image: New radar images show the A-74 iceberg spinning around the western tip of the Brunt Ice Shelf, brushing slightly against it before continuing southwards.

#earth #science #space #esa #europeanspaceagency
posted by pod_feeder_v2
 

Earth from Space: Malé, the Maldives


Image/Photo

Image/Photo

The Copernicus Sentinel-2 mission takes us over Malé – the capital and most populous city in the Republic of Maldives.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

Earth from Space: Malé, the Maldives


Image/Photo

Image/Photo

The Copernicus Sentinel-2 mission takes us over Malé – the capital and most populous city in the Republic of Maldives.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 
Apparently there's evidence of numerous star clusters which consist entirely of a bunch of black holes. The star cluster Palomar 5 may be in the transition - its center has lots of black holes, with visible stars stripping away
into streams.

https://www.space.com/black-holes-overrun-star-cluster-palomar-5-star-cluster



There are a number of other streams that aren't associated with any known visible source, so those could be actually associated with (invisible to us) pure black hole clusters.

I'm not sure whether such black hole clusters would be useful for anything in particular, but they could be a cool setting or maybe destination for a colony ship desperately trying to escape genocidal galactic berserkers ...

#Space #SpaceScience #Science #BlackHoles #Astronomy
 

Information Symmetries: Distribution vs. Assembly


I'm thinking again about communication, content, information, audiences, space, time, aggregation, and the like. This is all probably obvious, but writing it explicitly is helpful to me.
Networks distribute messages.

Spaces assemble audiences.

There are hybrid forms as well:

Media Channels combine distribution with an assembled audience.

Tours visit a series of audience across a travel path.

Archives gather records to spaces which readers can visit and access large quantities of information at little marginal cost (effort, time, distance, energy).

Note that "media channels" are distinct from the notion of a "signal channel" which I otherwise refer to simply as "channels".
"Tours" includes various synonyms: roadshows, travelling circus, conference series. "Archives" is principally aimed at a physical archive as in a library containing physical records, though the notion might be extended to online archives as well. Terminology concerning information and related domains (thought, ideas, knowledge, data) is tremendously difficult and confusing. Sorry.

Previously: Information symmetries of signals and records


This musing follows on a set of earlier thoughts on the symmetry between signals and records and their relations to energy, matter, time, space, media, and effects.

Signals transmit encoded symbolic messages from a transmitter across_ space_ through a channel by variations in energy over time to a receiver potentially creating a new record.

Records transmit encoded symbolic messages from a writer through a substrate across time by variations in matter over space to a reader potentially creating a new signal.

Again, there are hybrid forms as well, e.g., endocrine and chemical signalling systems are based on records (the encoded chemicals) but distribute much as signals (broadcast through space). Subatomic particles might be considered similarly. Synonyms for "receiver" include listener, viewer, audience, etc. "Channel" here is in the signal propagation sense. Note that a channel may be an omnidirectional broadcast, a directed transmission, or confined within a waveguide. These have distinct attributes as to direction, attenuation, noise, and audience.

Coctktail Party Communication Flows


It's observed that "you can go on little tours at a crowded party".

[1]On that ...

Public speaking for a long time was limited by the carrying power of a single human voice, and was long shaped by the acoustics of spaces (outdoor arenas, indoor chambers) in which those addresses were given. If you think through the characteristics of classical oratory (rhyme, meter, often musical accompanyment), these probably served mnemonic roles (in remembering the content, for the speaker), but might also have aided the audience in hearing (something I've just now thought of ... the mnemonic role is an older realisation).

Stone cathedrals and churches, with a horn-shaped pulpit (projecting the preacher's voice outwards to the pews), and a sing-song chant intonation (reverberates off the walls) likewise.

Modern audio capture, amplification, and speaker technology changed everything. German audio technology prior to and during WWII (mics, amps, speakers, magnetic audio tape) were strategic assets and game-changers. The Nueremberg Rallies and simultaneous nationwide taped addresses could not happen without those. (Bing Crosby played a major role in developing tape and audio tech in the US after the war, I believe with CiA / OSS support.)

Which is a prelude to the "tours at a party" comment.

A crowded party is a high-density social gathering usually without amplification, at least for speakers (and usually cover of music or other distraction, e.g., high noise, meaning high signal attenuation for any given speaker), making a set of small-n discussions (say, 2-10 people, and usually on the smaller side) possible. These are both serial (one person may speak or listen to numerous conversations) and simultaneous (there are numerous conversations happening at once).

The "cocktail party" scenario is a frequent one in various theoretical explorations in several domains (game theory, probability, etc., most dating to the CP's own heyday of roughly 1940 -- 1970 or so), though I haven't read anything specific to information/comms theory/studies that I recall. This might be interesting to research, suggested keywords "cocktail party problem", "cocktail party strategy", etc. There is notably the cocktail party effect, of focusing on a single conversatioin within a melieu, though that refers to attention and filtering by an individual rather than the overall informational flow. The notion of a city as a melenge of stories also occurs in literature and/or films, though I'm not recalling specific intances presently. And of course there is the economic notion of cities as supporting a high degree of differentiation and specialisation in economic roles and activities, observed since Adam Smith.

But Is There Maths?


Is there a mathematical expression of the signal/record relationshipi and symmetry? Um ... probably, though I'm going on thin ice here. I think what we'd be looking for might be something like:

Message characteristic: δe/δt * d * ε

Record: characteristic δm/δd * t * ε

Where
  • e: energy
  • m: mass
  • d: distance
  • t: time
  • ε: noise, error, entropy. Yes, that's a bit vague.
Not notationalised: encoding, direction, rate of propagation.

(I'm pretty sure that's wrong. It's conceptually ... interesting)

That's the "change in energy with time ... multiplied by? ... space" and "change in matter over distance ... multiplied by? ... time".

I'm pretty confident of the differential fraction term. The operation and the third term, not so much.

There's quite a bit of physics of signals and wave propagation, and the message equations might borrow from that. Also Claude Shannon. I'm not aware of a similar physics of records, per se, though some aspects of that, e.g., Newton's Laws of Motion, would apply. I'm reviewing my sources on these....

Note that signals also travel through time, and records also travel through space (more properly for both, within an inertial reference frame limited by their light cone) though the principle mode of propagation is as noted previously. Interesting cases might be cases of near-hybrid record-signal propagation where movement through space-time is roughly proportionate (also suggesting that encoding as mass-energy is also roughly proportionate).

On the Value of Abstraction


In reading and researching media, communications, language, and information theory over the past few years, some observations:
  • There's a lot of practice that's not especially aware of theory. Or even that theory might potentially exist.
  • Claude Shannon's work was absolutely revolutionary. "A Mathematical Theory of Communications" (1948)
  • Communications is a concept that spans numerous disciplines, many of which have their own individually-developed notions, nomenclatures, operations, communities, philosophies, contexts, and histories. Reinventing wheels is wildly popular.
  • There's almost always someone who's previously had thoughts similar to my own. A hobby has been having new-to-me "original" thoughts, then putting an effort into discovering who got there earlier. If I'm within a few decades of first emergence, I consider myself reasonably warm-on-trail. This applies genererally across domains, not merely information and media.
  • There's a lot of writing / discussion that's very implementation-specific to technology, craft, business or industry line, and the like. I like to look beyond that.
  • There's a great deal that's been written that I've not read. Of the works I have, Shanon's original paper on Inforation Theory, Jeremy Cambell's Grammatical Man, and James Gleick's Chaos have been invaluable. There are many, many other references, a few I've read though listing even those would be a stretch. Gleick and Campbell's own later works (The Lair's Tale and The Information) would be two I desperately want to read.
Identifying the abstract notions is very useful in finding patterns, and potential new developments. As an example, one idea that fell out of my information/signal/record symmetry notion was the realisation that channels and substrates (if you can think of a better single-word term for "recording medium" as distinct from "transmission medium", please do), was that each is characterised by a predictable ground state and a generally unconstrained state space that can be mapped to it.

Erwin Schroedinger came up with the notion of "aperiodic crystals" (I encountered this in Hofstadter's Goedel, Escher, Bach (1979)). Einstein pressaged the discovery of the maser and laser working with stimulated emissions of radiation. Lasers & masers are analogues of radio-frequency transmitters. Stone, clay, papyrus, paper, punch-cards, mag-tape, spinning rust, digital media (CD/DVD/BluRay) are all state-impressionalble media. Fourier transforms apply strongly to analogue signal encoding in signals.

Mind, I kind of half-grasp most of this, though could probably work my way through it given the initiative to do so and understanding of significance.

A prediction though is that matter states which are highly regular but arbitrarily modifiable will likely prove excellent storage media. I'm looking at you, graphene.
Adapted from a Mastodon thread with numerous corrections, expansions, and revisions: https://toot.cat/@dredmorbius/106388460596905072
Notes:#information #content #distribution #audience #eyeballs #time #space #records #signals #symmetry #performance #kfc
 

Moon habitat blueprint at Venice Biennale








A detailed concept for a lunar habitat, created by one of the world’s leading architectural firms with ESA technical support, is currently on show at the Biennale in Venice. Skidmore, Owings & Merrill, originator of many of the world’s tallest skyscrapers, worked with ESA on a semi-inflatable habitat design which could be part of a long-term vision for an international Moon settlement.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

Moon habitat blueprint at Venice Biennale








A detailed concept for a lunar habitat, created by one of the world’s leading architectural firms with ESA technical support, is currently on show at the Biennale in Venice. Skidmore, Owings & Merrill, originator of many of the world’s tallest skyscrapers, worked with ESA on a semi-inflatable habitat design which could be part of a long-term vision for an international Moon settlement.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

James Webb Space Telescope launch kit








Download this launch kit to learn more about the international James Webb Space Telescope and the science goals of the mission.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

James Webb Space Telescope launch kit








Download this launch kit to learn more about the international James Webb Space Telescope and the science goals of the mission.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 
Set the controls for the heart of the Sun...

Image/Photo

Gadget In Extremis: Parker Solar Probe becomes fastest human-made object


https://www.electronicsweekly.com/blogs/gadget-master/gadget-in-extremis/gadget-extremis-parker-solar-probe-becomes-fastest-human-made-object-2021-05/

Gadget In Extremis: Parker Solar Probe becomes fastest human-made object

Talk about setting the controls for the heart of the sun…NASA’s Parker Solar Probe is doing that, repeatedly, setting new records in the process.

Gadget In Extremis: Parker Solar Probe becomes fastest human-made object

The spacecraft is seeking to improve our understanding of the Sun and its changing conditions. It’s hot work, as the probe travels through the Sun’s atmosphere, closer to the surface than any spacecraft before it, “facing brutal heat and radiation conditions” in the words of NASA.

It represents the closest-ever observations of a star, and the craft has just made another science-gathering pass “across” its target. In the process it was moving faster than 330,000 miles per hour (532,000 kilometers per hour), beating its own previous record.

This is its eighth solar encounter, putting it one-third of the way through its planned journey of 24 progressively closer loops around the Sun, says NASA.

It’s trajectory can be seen below.

The agency writes:

“On May 2, 2021, at 3:00 a.m. EDT, mission controllers at the Johns Hopkins University Applied Physics Laboratory, in Laurel, Maryland, received a “tone one” beacon from Parker Solar Probe, indicating that all systems were healthy and operating normally after the spacecraft’s eighth close approach to the Sun on April 29.

During this close pass by the Sun — called perihelion — Parker Solar Probe broke its own records for spacecraft distance from the Sun and speed, coming to within about 6.5 million miles (10.4 million kilometers) of the Sun’s surface, while moving faster than 330,000 miles per hour (532,000 kilometers per hour).”

It was already the fastest-ever human-made object, thanks to its first solar encounter in October 2018. The spacecraft came within 15 million miles of the Sun’s surface and clocked a top speed of 213,200 miles per hour relative to the Sun (the top heliocentric speed by a spacecraft).

Amazing. You can read more about the probe on the NASA website.

Extreme Exploration



Using Venus’ gravity during the flybys, to gradually bring its orbit closer to the Sun, the probe is designed to unlock the mysteries of the Sun’s atmosphere.

“Parker Solar Probe performs its scientific investigations in a hazardous region of intense heat and solar radiation. The spacecraft will fly close enough to the Sun to watch the solar wind speed up from subsonic to supersonic, and it will fly though the birthplace of the highest-energy solar particles.

To perform these unprecedented investigations, the spacecraft and instruments are protected from the Sun’s heat by a 4.5-inch-thick (11.43 cm) carbon-composite shield, which needs to withstand temperatures outside the spacecraft that reach nearly 2,500 F (1,377 C).”

Launched back in August 2018, it’s named after the (living) physicist Eugene Newman Parker.

Cue, inevitably…

#Electronics #Space #Sun #ParkerSolarProbe
 
Set the controls for the heart of the Sun...

Image/Photo

Gadget In Extremis: Parker Solar Probe becomes fastest human-made object


https://www.electronicsweekly.com/blogs/gadget-master/gadget-in-extremis/gadget-extremis-parker-solar-probe-becomes-fastest-human-made-object-2021-05/

Gadget In Extremis: Parker Solar Probe becomes fastest human-made object

Talk about setting the controls for the heart of the sun…NASA’s Parker Solar Probe is doing that, repeatedly, setting new records in the process.

Gadget In Extremis: Parker Solar Probe becomes fastest human-made object

The spacecraft is seeking to improve our understanding of the Sun and its changing conditions. It’s hot work, as the probe travels through the Sun’s atmosphere, closer to the surface than any spacecraft before it, “facing brutal heat and radiation conditions” in the words of NASA.

It represents the closest-ever observations of a star, and the craft has just made another science-gathering pass “across” its target. In the process it was moving faster than 330,000 miles per hour (532,000 kilometers per hour), beating its own previous record.

This is its eighth solar encounter, putting it one-third of the way through its planned journey of 24 progressively closer loops around the Sun, says NASA.

It’s trajectory can be seen below.

The agency writes:

“On May 2, 2021, at 3:00 a.m. EDT, mission controllers at the Johns Hopkins University Applied Physics Laboratory, in Laurel, Maryland, received a “tone one” beacon from Parker Solar Probe, indicating that all systems were healthy and operating normally after the spacecraft’s eighth close approach to the Sun on April 29.

During this close pass by the Sun — called perihelion — Parker Solar Probe broke its own records for spacecraft distance from the Sun and speed, coming to within about 6.5 million miles (10.4 million kilometers) of the Sun’s surface, while moving faster than 330,000 miles per hour (532,000 kilometers per hour).”

It was already the fastest-ever human-made object, thanks to its first solar encounter in October 2018. The spacecraft came within 15 million miles of the Sun’s surface and clocked a top speed of 213,200 miles per hour relative to the Sun (the top heliocentric speed by a spacecraft).

Amazing. You can read more about the probe on the NASA website.

Extreme Exploration



Using Venus’ gravity during the flybys, to gradually bring its orbit closer to the Sun, the probe is designed to unlock the mysteries of the Sun’s atmosphere.

“Parker Solar Probe performs its scientific investigations in a hazardous region of intense heat and solar radiation. The spacecraft will fly close enough to the Sun to watch the solar wind speed up from subsonic to supersonic, and it will fly though the birthplace of the highest-energy solar particles.

To perform these unprecedented investigations, the spacecraft and instruments are protected from the Sun’s heat by a 4.5-inch-thick (11.43 cm) carbon-composite shield, which needs to withstand temperatures outside the spacecraft that reach nearly 2,500 F (1,377 C).”

Launched back in August 2018, it’s named after the (living) physicist Eugene Newman Parker.

Cue, inevitably…

#Electronics #Space #Sun #ParkerSolarProbe
 
Now the little chopper is REALLY moving!



See amazing video of Mars helicopter Ingenuity's boundary-stretching 3rd flight | Space


https://www.space.com/mars-helicopter-ingenuity-third-flight-video

See amazing video of Mars helicopter Ingenuity's boundary-stretching 3rd flight

By Mike Wall 5 hours ago

Ingenuity does some exploring on this hop.

NASA's Mars helicopter Ingenuity broke new ground during its latest Red Planet flight, as video of the sortie shows.

Ingenuity took off early Sunday morning (April 25) on its third and most ambitious Martian mission yet. The 4-lb. (1.8 kilograms) chopper traveled a total of 330 feet (100 meters) laterally, stayed aloft for 80 seconds and reached a maximum speed of about 4.5 mph (7.2 kph), smashing the marks set on its previous two flights.

"Today’s flight was what we planned for, and yet it was nothing short of amazing," Dave Lavery, the Ingenuity program executive at NASA Headquarters in Washington, said in a statement Sunday. "With this flight, we are demonstrating critical capabilities that will enable the addition of an aerial dimension to future Mars missions."

Video: Zoom in on Ingenuity helicopter's 1st flight on Mars

NASA's Mars helicopter Ingenuity takes its third flight on the Red Planet in this photo from the Perseverance rover taken on April 25, 2021.

NASA's Perseverance rover watched the action from about 210 feet (64 m) away on Sunday morning, capturing high-resolution video with its powerful Mastcam-Z camera system as it did on the previous flights. Ingenuity stayed in frame during those first two sorties, but it leaves the scene in the new footage, staying off-camera for about 24 seconds as it explores Wright Brothers Field, the name team members gave to its designated flying zone.

Perseverance and Ingenuity landed together on the floor of Jezero Crater on Feb. 18. The technology-demonstrating rotorcraft deployed from the rover's belly on April 3, starting the clock on Ingenuity's month-long flight campaign.

That campaign will include two more flights, if all goes according to plan. And flight number three could be just a warm-up act for what's to come: Ingenuity team members have said they intend to really push the helicopter's limits on the final two hops.
See more

Perseverance is a crucial part of this work, which is designed to show that aerial exploration is possible on Mars. In addition to serving as mission photographer, the car-sized rover is a relay station for Ingenuity, transmitting all communications to and from the little chopper.

But Perseverance needs to start focusing on its own mission soon, which is why Ingenuity gets just one month to fly on Mars. The rover has two main tasks: hunting for signs of ancient Mars life on Jezero's floor, and collecting and caching several dozen samples. A joint NASA-European Space Agency campaign will haul that pristine Red Planet material to Earth, perhaps as early as 2031.
#Space #Mars #Helicopter #Ingenuity #Aviation
 
Now the little chopper is REALLY moving!



See amazing video of Mars helicopter Ingenuity's boundary-stretching 3rd flight | Space


https://www.space.com/mars-helicopter-ingenuity-third-flight-video

See amazing video of Mars helicopter Ingenuity's boundary-stretching 3rd flight

By Mike Wall 5 hours ago

Ingenuity does some exploring on this hop.

NASA's Mars helicopter Ingenuity broke new ground during its latest Red Planet flight, as video of the sortie shows.

Ingenuity took off early Sunday morning (April 25) on its third and most ambitious Martian mission yet. The 4-lb. (1.8 kilograms) chopper traveled a total of 330 feet (100 meters) laterally, stayed aloft for 80 seconds and reached a maximum speed of about 4.5 mph (7.2 kph), smashing the marks set on its previous two flights.

"Today’s flight was what we planned for, and yet it was nothing short of amazing," Dave Lavery, the Ingenuity program executive at NASA Headquarters in Washington, said in a statement Sunday. "With this flight, we are demonstrating critical capabilities that will enable the addition of an aerial dimension to future Mars missions."

Video: Zoom in on Ingenuity helicopter's 1st flight on Mars

NASA's Mars helicopter Ingenuity takes its third flight on the Red Planet in this photo from the Perseverance rover taken on April 25, 2021.

NASA's Perseverance rover watched the action from about 210 feet (64 m) away on Sunday morning, capturing high-resolution video with its powerful Mastcam-Z camera system as it did on the previous flights. Ingenuity stayed in frame during those first two sorties, but it leaves the scene in the new footage, staying off-camera for about 24 seconds as it explores Wright Brothers Field, the name team members gave to its designated flying zone.

Perseverance and Ingenuity landed together on the floor of Jezero Crater on Feb. 18. The technology-demonstrating rotorcraft deployed from the rover's belly on April 3, starting the clock on Ingenuity's month-long flight campaign.

That campaign will include two more flights, if all goes according to plan. And flight number three could be just a warm-up act for what's to come: Ingenuity team members have said they intend to really push the helicopter's limits on the final two hops.
See more

Perseverance is a crucial part of this work, which is designed to show that aerial exploration is possible on Mars. In addition to serving as mission photographer, the car-sized rover is a relay station for Ingenuity, transmitting all communications to and from the little chopper.

But Perseverance needs to start focusing on its own mission soon, which is why Ingenuity gets just one month to fly on Mars. The rover has two main tasks: hunting for signs of ancient Mars life on Jezero's floor, and collecting and caching several dozen samples. A joint NASA-European Space Agency campaign will haul that pristine Red Planet material to Earth, perhaps as early as 2031.
#Space #Mars #Helicopter #Ingenuity #Aviation
 
An ISRU first - refining O2 and CO on Mars.

https://mars.nasa.gov/news/8926/nasas-perseverance-mars-rover-extracts-first-oxygen-from-red-planet/

Obviously, generating oxygen is very useful. Less obvious is that carbon monoxide can be a useful fuel. The specific impulse of a CO-LOX rocket could be over 300s, and realistically a specific impulse of 290s may be reasonable. This is good enough for an SSTO from Mars. It's also good enough for interplanetary missions from Mars.

Carbon dioxide could be harvested without landing on Mars or Venus, via orbital atmospheric scooping. This would allow mining satellites to generate fuel without dealing with various losses and operational difficulties of landing and launching.

#Space #SpaceExploration #SpaceTechnology
 
How #USA tried to derail #India's #space program https://in.yahoo.com/news/had-dream-dream-finished-nambi-103254308.html | #science #capitalism
 

Scanning Electron Telescopes vs Hard UV Lidar vs RADAR


So, I'm working on my Space Carrier VARUHARA setting, and have decided the ships and fighters and such will use stealth after all.

The Valhalla looks like a trapezoid slab, with a mirror sun shield on the shortest side and the catapult along the longest side. This side is also mirrored. The other four sides are black to absorb light from a nearby planet/moon.

The main thrusters use helium propellant when operating in contested space, which is really hard to see, but also hydrogen at periapsis where the planet/moon makes it hard to see.

Nevertheless, it's possible to sporadically detect the Valhalla when a sensor is in its reflected sunlight beam, or due to occultations.

But sporadic detections aren't good enough to directly hit a target with weapons.

What could they use for tracking? Here are a few candidates I've thought of:

1) Radar Radar stealth is good, but is it ever going to be perfect? Maybe just amp up the power enough, and radar's still the best option?

2) Hard UV Lidar Mirrors might defeat optical lidar, but hard UV or soft X-rays will produce backscatter no matter what. Is this a better option than radar?

3) Scanning Electron beam I'm not sure precisely how this would work, but basically the idea is to shine an electron beam at the target, and use telescopes to detect photons produced when it hits. Even if self repulsion might make an electron beam unsuitable for use as a high power weapon, it may be good enough to use in a sensor system?

Any ideas how these would compare? Any other good ideas?

Thanks!

#SpaceWarfare #SpaceTechnology #SpaceCombat #gizmo #Space #Astronomy
 

Stealth in Space - Helium propellant instead of LH2 propellant?


Hey, question for @Luke Campbell or @Rhysy or anyone who knows astronomy and stuff ... how visible would cold helium or cold molecular hydrogen exhaust be?

I know interstellar molecular hydrogen is notoriously difficult to detect; would that apply to hydrogen lit by sunlight from 1AU away? I'm guessing helium would be practically impossible to detect. Is that right? Or is it actually easier to detect due to its spectral lines?

Assume we're in interplanetary space vaguely near Earth. Would the exhaust get warmed up by sunlight, or scatter sunlight enough to be visible? I figure hydrolox exhaust would be visible due to the ice particles reflecting/refracting sunlight.

The stealth missile has a helium cooled mirror sunshade to reflect sunlight away in a narrow cone. There's also a side port to receive a laser which warms a heating element. The hot element does radiate light back toward the power laser, but it's unlikely enemy sensors will be lined up with that. OTOH, the laser path might be visible thanks to zodiacal dust? (I'm not sure.)

Anyway, small pulses of helium go through the helium element to produce thrust with a large expansion ratio. I think helium exhaust will be cool without an excessively bulky thruster, whereas that may be difficult with hydrogen due to the multi-atomic molecule. Specific impulse is perhaps 600s, which is more than enough for interplanetary missions.

Of course, liquid helium is going to be a lot more expensive than liquid hydrogen, and logistically challenging due to the increased boiloff. Liquid helium doesn't have much heat of vaporization, and of course its boiling temperature is colder.

If helium exhaust is practically invisible, then there may be no defense against these stealth missiles other than foiling enemy detection and/or tracking.

#SpaceWarfare #SpaceTechnology #SpaceCombat #gizmo #Space #Astronomy
 
Never knew #ISRO of #India offers the cheapest of launches even with expendable vehicles | #space #technology #science #rockets
 

Sharks on a Spacecraft?


Silly space movie idea - sharks in zero gee. But would they be able to breathe? Assume the air is very humid because all the water from the broken shark tanks have overwhelmed the air conditioning system. Thus, the gills don't dry out. In zero gee, would the gills be fine? Would they collapse?

Assuming the sharks can survive, their fins still won't be very effective so they'd be springing around and such in weird ways. Let's assume the sharks learn how to move around in zero gee air, snaking their way effectively through dense aeroponic gardens at least.

How would these sharks move, though? Obviously they can't use hand/foot bars effectively. Any ideas?

#Space
 
Image/Photo

Solid Rocket Space Missile Guidance Reconsidered ...


Most current space missiles use four liquid/gas divert thrusters arranged up/down/left/right.

But the old ASM-135 ASAT used a bunch of solid rocket thrusters with nozzles arranged around its waist.

https://airandspace.si.edu/sites/default/files/images/collection-objects/record-images/T20140036000cp01.jpg

You can see that the 64 solid rocket tubes are actually parallel to the body, but their nozzles are pointed outward sideways from the center of each tube. 56 of the thrusters are high thrust, while 8 of them are lower thrust for more fine adjustments. The entire MHV rotates at 30 revolutions per second, so continued thrust in a single direction is possible.

The Strix anti-tank mortar round uses a similar divert thruster system, with 12 solid rocket waist thrusters.

Well, for future space combat missiles, why not return to this style of solid rocket guidance? Compared to liquid/gas thrusters, I think solid rocket units could have better acceleration, and the delta-v is not necessarily much worse when you consider the 45 degree penalty of thrusting "between" the four cardinal directions.

Instead of a single layer of somewhat flattened nozzles, I imagine two staggered layers of bell nozzles, one slightly angled forward and the other slightly angled rearward so they all point through the center of mass. And each solid rocket chamber could be partitioned into 4 charge pulses. That way, you could have 64 efficiently large nozzles and 256 charges - some bigger and some smaller.

Compared to a liquid/gas thruster system, this is perhaps cheaper to mass produce and less maintenance. It might also be more compact. But I think the really interesting advantage is that it could be used for a gun launched projectile rather than boosted by a rocket. The projectile might have a stealthy flat face. Note that a gun would typically need to lead the target by a lot in space, so this face will not reflect radar/lidar beams directly back to the target. The face might be pointed, say, 30 degrees away from the target.

This could be an extreme challenge to defend against. It might be impossible to target an incoming guided projectile until it lights up a divert thruster. You might be compelled to perform an occasional evasive maneuver simply to force incoming projectiles to divert.

For guidance, a rear facing receiver could be used for command guidance and/or receive navigation beam data. For example, a beam spiral scanning around the target could implicitly guide multiple projectiles by informing of their relative location compared to the target.

More thoughts on implications for space combat maneuvering and engine/weapon layout to come...

#SpaceWarfare #SpaceTechnology #SpaceCombat #gizmo #Space
 
I'm trying to figure out what are all the basic real life space missile designs so far.

AFAIK, the main design is used by SM-3, THAAD, EKV, etc ... a fixed forward facing sensor and four waist divert thrusters (up/down/left/right). This seems to be the most common design, and it's pretty intuitive. The kill vehicle doesn't rotate, it just stares forward and uses divert thrusters to try and zero out any angular velocity of the target image across the sensor. This is similar to the
"windscreen" principle. If you're flying an aircraft and the enemy is shooting AAA, any tracers that look like a dot on the windscreen are ones headed toward you.

Then there's the Israeli Arrow-3. I'm not 100% clear on what type of rocket thruster is used, but it's fixed to the body. The sensor can point sideways. So, it can't instantly divert in any direction. It must "turn and burn". But a single main thruster weighs less than four thrusters, and it can maneuver "diagonally" more efficiently. Also, it's okay for the center of mass to shift as fuel is consumed.

The ASM-135 ASAT used clusters of single shot thrusters around the cylindrical body, similar to the Dragon missile. I think this style of missile guidance has not endured the test of time. Like the Dragon, it revolved so it would be possible to repeatedly thrust in one direction even though the thruster units are distributed all around.

I don't know if there are any others. There are a number of ASAT and exoatmospheric ABM missiles I know nothing about.

Oh, there's also Deep Impact's Impactor. I think it had one main thruster, pointed sideways, and a few small maneuvering thrusters. I'm not sure whether it used "turn and burn" or if it just rotated and timed its main thruster thrusts according to when it was rotated in the desired direction.

Anyone know?

Thanks!

#Space #SpaceTechnology
 

Giant iceberg breaks off Brunt Ice Shelf in Antarctica






Image: New Copernicus Sentinel-1 radar images show a giant iceberg breaking off from the northern section of Antarctica’s Brunt Ice Shelf

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

Giant iceberg breaks off Brunt Ice Shelf in Antarctica






Image: New Copernicus Sentinel-1 radar images show a giant iceberg breaking off from the northern section of Antarctica’s Brunt Ice Shelf

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 

A Look at The “Risky” Tech in NASA’s Martian Helicopter





#science #space #helicopter #mars #marsrover #opensource #perseverance #hackaday
posted by pod_feeder_v2
A Look at The “Risky” Tech in NASA’s Martian Helicopter
 

A Look at The “Risky” Tech in NASA’s Martian Helicopter





#science #space #helicopter #mars #marsrover #opensource #perseverance #hackaday
posted by pod_feeder_v2
A Look at The “Risky” Tech in NASA’s Martian Helicopter
 

Satellite radar interferometry effective for mapping crops








Traditionally, optical, or ‘camera-like’, satellite images are used to map different crops from space, but a recent study shows that Copernicus Sentinel-1 radar data along with interferometric processing can make crop-type mapping even better. This, in turn, will help improve crop-yield forecasts, production statistics, drought and storm damage assessments, and more.

#earth #science #space #esa #europeanspaceagency
posted by pod_feeder_v2
 
Can't believe #UAE sent a probe to Mars. I thought they always stuck to #Quran which said Earth was flat and Sun goes around us. Isn't death the punishment of disobeying #Islam? | #religion #science #space #technology #mars
 

Watch live: ESA outlines its search for astronauts








For the first time in over a decade, the European Space Agency (ESA) is seeking new astronauts. Tune in to ESA Web TV on Tuesday 16 February from 13:00 CET (12:00 GMT) for briefings in six languages and all you need to know.

#news #space #science #esa #europeanspaceagency
posted by pod_feeder_v2
 
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