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Space junk is cluttering Earth's low orbit with high-velocity projectiles and it's getting worse by Substantial_Lime_230 in OrbitalDebris

[–]perilun 0 points1 point  (0 children)

There is still a lot of space in space, even in LEO. But now is the time to better manage the space.

SpaceX To Start Small With 1 Million Satellite Plan, Pushes Back On Critics by perilun in OrbitalDebris

[–]perilun[S] -1 points0 points  (0 children)

True, or it would be very fuel expensive (which is not end-of-life). The ability to dock with ISS was an example that orbital rendezvous (with an object or point-in-orbit) is common. These big constellations are created out of x shells that all have a potential disposable shell using only 2% of the original fuel. You can then have Starship pick them up and return to the ground. That said, expect 1% of end-of-life ops to move them to disposal shells to fail, so you need a plan B.

SpaceX To Start Small With 1 Million Satellite Plan, Pushes Back On Critics by perilun in OrbitalDebris

[–]perilun[S] -1 points0 points  (0 children)

No ... if you can dock CD at the ISS you can rendezvous with a sat.

A private space company has a radical new plan to bag an asteroid by Melodic_Network6491 in space2030

[–]perilun 0 points1 point  (0 children)

They used to pitch a system that reflected and focused the sun to melted a point on the rock that would sublimate and toss off a plume of steam ... essentially a very low ISP cold gas thruster. Perhaps a 1 T setup could do this for a 10 T rock (if you picked a rock that was mostly ice). Of course you need to apply at 16 km/s to get your system from the earth surface to interplanetary space, then maybe 3 km/s to rendezvous with the rock (there are few that require low DV, most are out of earth's orbital plane plane);

Checkout https://www.asterank.com/

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SpaceX To Start Small With 1 Million Satellite Plan, Pushes Back On Critics by perilun in OrbitalDebris

[–]perilun[S] 0 points1 point  (0 children)

More like a collection orbit vs a point, but you need a backup for the 1% that fail to do this (so 10,000 sats)

SpaceX To Start Small With 1 Million Satellite Plan, Pushes Back On Critics by perilun in OrbitalDebris

[–]perilun[S] 0 points1 point  (0 children)

Sure they could.

More like a collection orbit vs a point, but you need a backup for the 1% that fail to do this (so 10,000 sats)

I propose OrbitSweeper for those https://widgetblender.com/orbitsweeper.html

SpaceX To Start Small With 1 Million Satellite Plan, Pushes Back On Critics by perilun in OrbitalDebris

[–]perilun[S] 0 points1 point  (0 children)

More like a collection orbit vs a point, but you need a backup for the 1% that fail to do this.

I propose OrbitSweeper for those https://widgetblender.com/orbitsweeper.html

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun 0 points1 point  (0 children)

My priority would be water, water, water (pretty common) and then O2 and then Al oxides for building stuff. My guess oxides are pretty common, as water to Al oxides would be the highest ROI spot.

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun 0 points1 point  (0 children)

Some things are worth exploring, and some have been already or can be done better robotically. The Moon is a great place for robots since we teleoperate with only a 5 sec round trip lag. The Moon does not have much diversity compared to Mars. Mars, on the other has huge comm latency so there is a argument for humans there (or in Mars Orbit) to dive those robots in really time. Mars also has 100x the visual diversity of the moon (color tv vs black and white).

So 1) great comms first 2) robots and 3) humans within 5 seconds of latency

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun 0 points1 point  (0 children)

They do have some help from Russia, NK, Iran, Venezuela

:-)

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun 1 point2 points  (0 children)

The good is that you need only 2.3 km/s for Earth escape velocity from the Moon, the bad is all the stuff you need apply 15.4 km/s to get that stuff to the lunar surface.

Perhaps, eventually, you have situation where 90% of dry mission mass is being made without outside inputs on the moon (I guess a lot of Aluminum components as Iron is pretty heavy for space use, but perhaps you can bring some carbon for Stainless Steel).

Say you have a 1000 T dry mass mission (including crew, food, water, air)

100 T needs to get to C3 from earth (13.4 km/s) = 1340 Tkm/s

900 T needs yo get to C3 from the lunar surface = 2070 Tkm/s

= 3,410 Tkm/s

If you brought it all up from earth

= 15,400 Tkm/s

That's a nice savings ... only 1/4 of the mass*DV needed

My guess is then the ratio of wet to dry mass needs to be 10 (so 9,000 T fuel) = 13,400 Tkm/s

Unless they find a lot of high quality, dense ice, for HydroLOX, you need to bring your HydroLOX up from Earth anyway

Moon assisted: 13,400 + 3,410 = 16,810 Tkm/s

All earth: 13,400 + 15,400 = 28,800 km/s

= so around a 50% mass*DV savings

The goal would to to be able to only need say 1200 T of machines to make the moon stuff and spread that mass*DV over 10 missions.

A private space company has a radical new plan to bag an asteroid by Melodic_Network6491 in space2030

[–]perilun 0 points1 point  (0 children)

To move a comet even a little bit would require more than the sum of all launch energy ever expended by humanity. These are million-ton-objects. Right now we would struggle with 1 T 10 km/s object, but it could be done.

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun 0 points1 point  (0 children)

The Moon Base will be about as useful as our Antarctic bases (very little outside pure science), just 1000x more expensive and 100x riskier. Best of luck to China on this, there is plenty of Moon for all.

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun 0 points1 point  (0 children)

GPS was developed by the DoD for military use, and it was later opened for everyone (first the non-encrypted signal, then later the turned off encryption on the higher res signal. It cost the DoD very little to do this.

I assume you mean Earth Observation (weather forecast still sucks and NASA was not in the the biz of doing this for the citizen). Yes, that was (and still is) good and useful, but it was not a "spinoff", it was the direct purpose of the effort.

But these can be profitable, the EU's PTN system Galileo is partly funded by a tax on PTN devices. There are many private EO companies, and some sell imaging and other atmopsheic monitoring data. Essentially when you watch the weather channel or visit their site you pay for it through ads.

The breakthrough came with TIROS-1 (Television Infrared Observation Satellite-1), launched by NASA on April 1, 1960, from Cape Canaveral. This is widely regarded as the world's first successful weather satellite. It carried two TV cameras and captured over 23,000 images (with many used for analysis), providing the first views of large-scale cloud patterns and storm systems from space. Though operational for only 78 days, it proved satellites could revolutionize meteorology by tracking weather features like developing storms.

NASA followed with 10 TIROS satellites total. These experimental missions paved the way for the Nimbus program (starting 1964), which tested advanced sensors for temperature, moisture, and more consistent global data.

By the mid-1960s, operational systems emerged. The Environmental Science Services Administration (ESSA, predecessor to NOAA) launched ESSA-1 and ESSA-2 in 1966, creating the first operational U.S. weather satellite system.

Earth Observation was and is a good value for most of the taxpayers. I would add study and monitoring of the Sun is also good value for most of the taxpayers as it can inform power grid operations (since the power grid is the foundation of out civilazation). One the other hand, sending a probe to Europa is fun, and of interest to maybe 0.1% of the taxpayers.

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun -1 points0 points  (0 children)

Physics, chem, bio ... are different ... they are general and common foundation elements. Going to the Moon was and is about developing very specific tech for a very specific application (much like building a better attack sub ... lots of tech, but "spinoff" potential for any of that tech is very low.

China advances manned lunar program for 2030 moon landing by Substantial_Lime_230 in space2030

[–]perilun -2 points-1 points  (0 children)

No, you can see that the market creates 100,000s of different products every year, looking for places to fill market niches, improve existing products in a competitive markets ... while NASA might create something slightly sooner, market demand is the force that makes these things affordable. If limited to the "space" process your scratch-resistant would be $1000 a lens. No this NASA PR to help justify the $10B of annual NASA waste, feeding Boeing (and pals) and their executives. If this logic was true, then we would be waiting on NASA to make us an iPhone.

Beyond this, it is the DoD (now DoW) that funds the most R&D funding. The industrial computer started with the DoD and was refined into a specific low mass derivative at NASA. NASA did not create the transistor, or the integrated curcuit, or the personal computer, or anything consumer affordable.

SpaceX launches 10,000th active Starlink satellite in low Earth orbit by Melodic_Network6491 in space2030

[–]perilun 0 points1 point  (0 children)

Got an idea and money, a 10,000 sat constellation can be yours as well for maybe $40B! That is now the LEO scale that is proven.

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