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~- Φiφteen reasons φor Φobos φirst -~
On my todo list is a paper: "Phiphteen reasons phor Phobos
phirst". It seems to be growing to "Phipfty reasons..."
Line 6: Line 3:
A too-long summary follows: On my todo list is writing a paper: "Phiphteen reasons phor Phobos
phirst". It seems to be growing to "Phipfty reasons..." A too-long "summary" follows:
Line 8: Line 6:
Mars life would have diverged radically as conditions
worsened, evolving towards biochemical "Life 2.0". Surviving
molecular traces will likely be rare, but if we find them,
they can add a long-baseline parallax view of molecular biology,
greatly expanding the range of artificial bioengineering.
Even if ''hypothetical'' Mars life  shared early ancestry with Earth, it would have diverged radically as conditions worsened, evolving towards biochemical "Life 2.0" compared to different-conditions Earth. Surviving molecular traces will likely be rare, but if we find them, they can add a long-baseline parallax view of molecular biology, greatly expanding the range of artificial bioengineering.
Line 14: Line 8:
The hunt for those rare molecules might take decades, processing
tonnes of candidate rock samples, but the long term economic
benefit of artificial life that is mutually indigestible
might be
worth quadrillions of dollars.
The hunt for those rare Martian molecules might take decades, processing tonnes of candidate rock samples, but the long term economic benefit of artificial life that is mutually indigestible with Earth Life 1.0 might be worth quadrillions of dollars.
Line 21: Line 12:
A manned lander crashing into Mars after a nine month
journey from Earth will carry many "human-poop-years" of
gut microbes; "kilo-Avogadros" of bio-molecules, dispersed
by impact and the Martian winds. Finding a few trace
Martian xeno-molecules with that overpowering
noise signal would be practically impossible.
A manned lander crashing into Mars after a nine month journey from Earth will carry many "human-poop-years" of gut microbes; "kilo-Avogadros" of bio-molecules, dispersed by impact and the Martian winds. Finding a few trace Martian xeno-molecules with that overpowering noise signal would be practically impossible.  
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Mars is a terrible place to live. A healthy habitat
requires thick radiation shielding and near-one-gee
centrifugal gravity. Ask Joan Vernikos, retired
NASA biology leader, about "gee".
Mars is a terrible place to live. A healthy habitat requires thick radiation shielding and near-one-gee centrifugal gravity. Ask [[https://www.joanvernikos.com | Dr. Joan Vernikos ]], retired NASA life sciences director, about "gee".
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Recent research suggests that most "Martian polar ice" may
actually be smectite clay with the same radar signature.
See the July 2021 Geophysical Research Letters "A Solid
Interpretation of Bright Radar Reflectors Under the Mars
South Polar Ice" https://doi.org/10.1029/2021GL093618
Recent research suggests that most "Martian polar ice" may actually be smectite clay with the same radar signature.   See the July 2021 Geophysical Research Letters "A Solid Interpretation of Bright Radar Reflectors Under the Mars South Polar Ice" https://doi.org/10.1029/2021GL093618
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------------------------------------------------------
Phiphteen reasons phor Phobos phirst:
------------------------------------------------------
A manned station on a ***Phobos pole***, controlling
robots on the surface via arrays of small relay
satellites, is a much better place for survival:
------------------------------------------------------
--------
=== Phiphteen reasons phor Phobos phirst ===
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*** 4 km/s less delta V between Earth and Phobos, compared
to the Mars surface, and 4 km/s less return delta V.
Vastly more mass can be delivered for the same Earth launch.
A manned station on a '''''Phobos pole''''', controlling robots on the surface via arrays of small LMO "low Mars orbit" relay satellites, is a much better place for survival:
------
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*** Direct Phobos landing by the interplanetary vehicle.
Phobos surface gravity is 600 microgees, and escape
velocity is 11 meters per second.
1) 4 km/s less delta V between Earth and Phobos, compared to the Mars surface, and 4 km/s less return delta V. Vastly more mass can be delivered for the same Earth launch.
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*** Robotic pre-manned-mission construction - launch crew
AFTER there is a safe and tested place for them to live.
2) Direct Phobos landing by the interplanetary vehicle. Phobos surface gravity is 600 microgees, and escape velocity is 11 meters per second.
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*** A 10 meter fractional wheel vertical axis centrifuge
(10 rpm, (1 gee) habitat. It can be dimensionally and
functionally identical to the interplanetary mission
spacecraft itself, so that in an emergency, the habitat
can be detached from Phobos and used to return to Earth.
3) Robotic pre-manned-mission construction - launch crew AFTER there is a safe and tested place for them to live.
Line 64: Line 30:
*** A nuclear power source at the other end of the arm,
shielded by the 10 meter plug of rock in the center.
Consumables and waste shifted across the arm for balance.
4) A 10 meter fractional wheel vertical axis centrifuge, 10 rpm (1 gee) habitat. It can be dimensionally and functionally identical to the interplanetary mission spacecraft itself, so that in an emergency, the habitat can be detached from Phobos and used to return to Earth.
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*** A 20 Pascal-loaded cantilever tent supports 3 meters
of rock shielding. The habitat itself is cantilevered
off the rotating arm to circle in a trench under the tent.
5) A nuclear power source at the other end of the arm, shielded by the 10 meter plug of rock in the center. Consumables and waste shifted across the arm for balance.
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*** Crew ingress/egress up the arm to the pivot, then over
ziplines from the pivot to locations the outside surface.
6) A 20 Pascal-loaded cantilever tent supports 3 meters of rock shielding. The habitat itself is cantilevered off the rotating arm to circle in a trench under the tent.
Line 75: Line 36:
*** A crew of humanity's most clever and versatile
instrument builders on the spot, assembling new analytical
instruments from component stockpiles. Delivering
assembled probes to the Martian surface to follow up new
discoveries as they are made. Discovery-driven science
packages can be constructed and delivered anywhere on
the Martian surface in days, not decades.
7) Crew ingress/egress up the arm to the pivot, then over ziplines from the pivot to locations the outside surface.
Line 83: Line 38:
*** Or to repair the crew habitat or return vehicle ...
Imagine Apollo 13, but using local resources to build and
replenish a new LOX tank.
8) A crew of humanity's most clever and versatile instrument builders on the spot, assembling new analytical instruments from component stockpiles. Delivering assembled probes to the Martian surface to follow up new discoveries as they are made. Discovery-driven science packages can be constructed and delivered anywhere on the Martian surface in days, not decades.
Line 87: Line 40:
*** 85% sunlight to rotating sun-tracking photovoltaics.
Phobos axial tilt is 26 degrees to the ecliptic, "night"
is a one hour Mars eclipse every 7 hour 40 minute orbit.
9) Or to repair the crew habitat or return vehicle ... Imagine Apollo 13, but using local resources to build and replenish a new LOX tank.
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*** Base-local polar PV is good for half the Martian year.
After arrival, during Phobos-polar summer, build a high
voltage power line to the opposite pole of Phobos, 10 km
away, migrating most of the solar panels twice Mars-annually.
10) 85% sunlight to rotating sun-tracking photovoltaics. Phobos axial tilt is 26 degrees to the ecliptic, "night" is a one hour Mars eclipse every 7 hour 40 minute orbit.
Line 96: Line 44:
*** 90% of Mars surface is in direct view every 8 hours,
the rest via observation and relay satellites in polar orbit.
11) Base-local polar PV is good for half the Martian year. After arrival, during Phobos-polar summer, build a high voltage power line to the opposite pole of Phobos, 10 km away, migrating most of the solar panels twice Mars-annually.
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*** TINY and NUMEROUS Mars surface robots, just big enough
to carry a science package, and track and laser-link to
orbiting relay satellites overhead. Terabytes per day
collected on Phobos, then "big optics laser-linked" direct
to Earth, or relays at Earth-Sun L4-L5 during conjunction.
12) 90% of Mars surface is in direct view every 8 hours, the rest via observation and relay satellites in polar orbit.
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*** All the talent of Earth hours away to interpret data
and choose the next opportunities, while engineering teams
design and test the next instruments to be assembled and
landed from the mission's component stockpile.
13) TINY (sub-kilogram) and NUMEROUS Mars surface robots, just big enough to carry a science package, and track and laser-link to orbiting relay satellites overhead. Terabytes per day collected on Phobos, then "big optics laser-linked" direct to Earth, or relays at Earth-Sun L4-L5 during conjunction.
 13a) The laser uplink can be a Vertical Cavity Surface Emitting Laser, VCSEL mounted on an electrostatically steered micromirror, a few milligrams, observed with a tracking telescope on the relay satellite orbiting (WAG) 100 kilometers overhead and +- 200 km crossrange.
Line 110: Line 51:
*** WE DON'T KNOW WHAT WE WILL DISCOVER, and what we will
choose to focus on after we discover it. A versatile base
that can connect in milliseconds to small robots everywhere
on Mars will allow us to deploy situationally unique robots
in days to follow up new discoveries.
14) All the talent of Earth hours away to interpret data and choose the next opportunities, while engineering teams design and test the next instruments to be assembled and landed from the mission's component stockpile.
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... and MANY other advantages, too numerous for an email. 15) WE DON'T KNOW WHAT WE WILL DISCOVER, and what we will choose to focus on after we discover it. A versatile base that can connect in milliseconds to small robots everywhere on Mars will allow us to deploy situationally unique robots in days to follow up new discoveries.
Line 118: Line 55:
No more spam in a can. Send Homo Faber, return Earth-saving
discoveries soonest, while keeping Mars clean and sterile.
... and MANY other advantages, will be added soon.

No more spam in a can. Send Homo Faber, return Earth-saving discoveries soonest, while keeping Mars clean and sterile.

 - We've spent 4 billion years evolving in and trillions of dollars (mostly for weapons development) to climb out of Earth's habitable gravity well (escaping those weapons).

 - Why spend more trillions to ruin another unique but life-hostile gravity well, when there are millions of asteroids and comets to convert from threats to economic bonanzas?

 - Why accept exo-planetary surface contamination and tiny Carnot efficiencies, when gossamer mirrors in interplanetary nano-gravity and vacuum offer a 5700 Kelvin heat source and a 3 Kelvin heat sink?

Paraphrasing Tsiolkovsky, why climb out of our cradle full of baby poop, only to drop into another inferior cradle and make more baby poop, obliterating the priceless scientific messages written on it?
 
ps: is "Φiφteen reasons φor Φobos φirst" indexable?
Line 123: Line 71:
 - We've spent 4 billion years evolving in and trillions of
dollars (mostly for weapons development) to climb out of
Earth's habitable gravity well (escaping those weapons).
== Addendum, More reasons: ==
Line 127: Line 73:
 - Why spend more trillions to ruin another unique but life-
hostile gravity well, when there are millions of asteroids
and comets to convert from threats to economic bonanzas?
16) If "footsteps on Mars" are required for geopolitical and funding and morale reasons, the landing should be a brief two-crew excursion from the capable (if under construction) base on Phobos. Two lander+return vehicles will be available, plus spare parts. Homo Faber technicians at the base will thoroughly test both vehicles after arrival but before deployment. They will land an uncrewed backup vehicle first, while monitoring telemetry from the lander, and from video from robots stationed nearby. If all goes well, a three day visit to make speeches, launch golf balls, etc. If the crewed lander is disabled, the astronauts can return in the spare ascent vehicle. If accident disables both astronauts, the robots should be able to carry them into the ascent vehicle and send them back to Phobos base. Worst case, the robots also remediate any bio-contamination an accident might cause, so that does not spread beyond the landing site.
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 - Why accept planetary surface contamination and tiny Carnot
efficiencies, when gossamer mirrors in interplanetary
nano-gravity and vacuum offer a 5700 Kelvin heat source
and a 3 Kelvin heat sink?
17) Partial space elevator: A surface-to-beyond-geostationary space elevator requires unobtanium for planets as large as Mars. However, using available engineering materials and 20x taper ratios, an orbiting space elevator hanging Marsward from Phobos can reach down close to the top of the Martian atmosphere, with enough pendulum action to subtract most of the angular velocity. Phobos average orbital velocity is 2138 m/s at 9376 km average radius. Projected to 200 km above the Martian equator (3396 + 200 → 3596 km radius) at Phobos periapsis (9236 km) yields a tether length of 5640 km, an average bottom radius of 3736 km, for an average tip speed of (3736/9376)*2138 m/s → 852 m/s, relative to a Mars equatorial rotation velocity of ( 2π * 3396000m / ( 24.6229 * 3600s ) ) → 241 m/s, for an average relative speed of 611 m/s. That is considerably slower than 5030 m/s escape velocity - a supersonic glider can use that velocity to provide considerable cross-range.
Line 136: Line 77:
Paraphrasing Tsiolkovsky, why climb out of a cradle full
of baby poop, only to drop into another inferior cradle
with more baby poop, obliterating the priceless scientific
messages written on it?
 
ps: is "Φiφteen reasons φor Φobos φirst" indexable?
18) Pendulum space elevator: A stronger and cleverly tapered space elevator can be designed to oscillate like a pendulum, rotating at the bottom with additional velocity, actually landing on the Martian surface with zero relative velocity at Phobos periapsis. Martian landers can descend the tether synchronized to the swing, converting forward momentum into more swing, and reach a roll-on/roll-off platform at the bottom. This would obviate the need for rockets, though the descent mechanism must dissipate a lot of heat. A subsequent ascent would be slow and require too much energy.

 '''Space elevator note:''' Megastructure tethers are amusing to contemplete, and may be physically realizable, but they are slow, and cannot access all of Mars beyond a narrow band around the Martian equator. Tether systems may be useful for mature Martian civilization, but they are a time-wasting distraction for Martian mission design. Do the math, and be ready to educate and refocus time-wasting "visionaries", so they do not divide attention and delay deployment of the core mission.


-----

Acknowledgment: The brilliant Dr. Geoffrey Landis at NASA Glenn developed the core principles first, decades ago:

[[ Footsteps to Mars: An incremental approach to Mars exploration | http://www.geoffreylandis.com/Footsteps.pdf ]] Journal of the British Interplanetary Society, Vol. 48, pp. 367-342 (1995) Geoffrey A. Landis, NASA John Glenn Research Center 302-1, 21000 Brookpark Rd., Cleveland, OH 44135

[[ Teleoperation from Mars orbit: A proposal for human exploration☆| https://doi.org/10.1016/j.actaastro.2006.12.049 ]] Acta Astronautica Volume 62, Issue 1, January 2008, Pages 59-65

-----
Other References:
  
[[ NASA's Mars Fact Sheet | https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html ]]

Phifteen Reasons phor Phobos phirst

On my todo list is writing a paper: "Phiphteen reasons phor Phobos phirst". It seems to be growing to "Phipfty reasons..." A too-long "summary" follows:

Even if hypothetical Mars life shared early ancestry with Earth, it would have diverged radically as conditions worsened, evolving towards biochemical "Life 2.0" compared to different-conditions Earth. Surviving molecular traces will likely be rare, but if we find them, they can add a long-baseline parallax view of molecular biology, greatly expanding the range of artificial bioengineering.

The hunt for those rare Martian molecules might take decades, processing tonnes of candidate rock samples, but the long term economic benefit of artificial life that is mutually indigestible with Earth Life 1.0 might be worth quadrillions of dollars.

Direct human exploration could preclude this forever.

A manned lander crashing into Mars after a nine month journey from Earth will carry many "human-poop-years" of gut microbes; "kilo-Avogadros" of bio-molecules, dispersed by impact and the Martian winds. Finding a few trace Martian xeno-molecules with that overpowering noise signal would be practically impossible.

Mars is a terrible place to live. A healthy habitat requires thick radiation shielding and near-one-gee centrifugal gravity. Ask Dr. Joan Vernikos, retired NASA life sciences director, about "gee".

Recent research suggests that most "Martian polar ice" may actually be smectite clay with the same radar signature. See the July 2021 Geophysical Research Letters "A Solid Interpretation of Bright Radar Reflectors Under the Mars South Polar Ice" https://doi.org/10.1029/2021GL093618


Phiphteen reasons phor Phobos phirst

A manned station on a Phobos pole, controlling robots on the surface via arrays of small LMO "low Mars orbit" relay satellites, is a much better place for survival:


1) 4 km/s less delta V between Earth and Phobos, compared to the Mars surface, and 4 km/s less return delta V. Vastly more mass can be delivered for the same Earth launch.

2) Direct Phobos landing by the interplanetary vehicle. Phobos surface gravity is 600 microgees, and escape velocity is 11 meters per second.

3) Robotic pre-manned-mission construction - launch crew AFTER there is a safe and tested place for them to live.

4) A 10 meter fractional wheel vertical axis centrifuge, 10 rpm (1 gee) habitat. It can be dimensionally and functionally identical to the interplanetary mission spacecraft itself, so that in an emergency, the habitat can be detached from Phobos and used to return to Earth.

5) A nuclear power source at the other end of the arm, shielded by the 10 meter plug of rock in the center. Consumables and waste shifted across the arm for balance.

6) A 20 Pascal-loaded cantilever tent supports 3 meters of rock shielding. The habitat itself is cantilevered off the rotating arm to circle in a trench under the tent.

7) Crew ingress/egress up the arm to the pivot, then over ziplines from the pivot to locations the outside surface.

8) A crew of humanity's most clever and versatile instrument builders on the spot, assembling new analytical instruments from component stockpiles. Delivering assembled probes to the Martian surface to follow up new discoveries as they are made. Discovery-driven science packages can be constructed and delivered anywhere on the Martian surface in days, not decades.

9) Or to repair the crew habitat or return vehicle ... Imagine Apollo 13, but using local resources to build and replenish a new LOX tank.

10) 85% sunlight to rotating sun-tracking photovoltaics. Phobos axial tilt is 26 degrees to the ecliptic, "night" is a one hour Mars eclipse every 7 hour 40 minute orbit.

11) Base-local polar PV is good for half the Martian year. After arrival, during Phobos-polar summer, build a high voltage power line to the opposite pole of Phobos, 10 km away, migrating most of the solar panels twice Mars-annually.

12) 90% of Mars surface is in direct view every 8 hours, the rest via observation and relay satellites in polar orbit.

13) TINY (sub-kilogram) and NUMEROUS Mars surface robots, just big enough to carry a science package, and track and laser-link to orbiting relay satellites overhead. Terabytes per day collected on Phobos, then "big optics laser-linked" direct to Earth, or relays at Earth-Sun L4-L5 during conjunction.

  • 13a) The laser uplink can be a Vertical Cavity Surface Emitting Laser, VCSEL mounted on an electrostatically steered micromirror, a few milligrams, observed with a tracking telescope on the relay satellite orbiting (WAG) 100 kilometers overhead and +- 200 km crossrange.

14) All the talent of Earth hours away to interpret data and choose the next opportunities, while engineering teams design and test the next instruments to be assembled and landed from the mission's component stockpile.

15) WE DON'T KNOW WHAT WE WILL DISCOVER, and what we will choose to focus on after we discover it. A versatile base that can connect in milliseconds to small robots everywhere on Mars will allow us to deploy situationally unique robots in days to follow up new discoveries.

... and MANY other advantages, will be added soon.

No more spam in a can. Send Homo Faber, return Earth-saving discoveries soonest, while keeping Mars clean and sterile.

  • - We've spent 4 billion years evolving in and trillions of dollars (mostly for weapons development) to climb out of Earth's habitable gravity well (escaping those weapons). - Why spend more trillions to ruin another unique but life-hostile gravity well, when there are millions of asteroids and comets to convert from threats to economic bonanzas? - Why accept exo-planetary surface contamination and tiny Carnot efficiencies, when gossamer mirrors in interplanetary nano-gravity and vacuum offer a 5700 Kelvin heat source and a 3 Kelvin heat sink?

Paraphrasing Tsiolkovsky, why climb out of our cradle full of baby poop, only to drop into another inferior cradle and make more baby poop, obliterating the priceless scientific messages written on it?

ps: is "Φiφteen reasons φor Φobos φirst" indexable?


Addendum, More reasons:

16) If "footsteps on Mars" are required for geopolitical and funding and morale reasons, the landing should be a brief two-crew excursion from the capable (if under construction) base on Phobos. Two lander+return vehicles will be available, plus spare parts. Homo Faber technicians at the base will thoroughly test both vehicles after arrival but before deployment. They will land an uncrewed backup vehicle first, while monitoring telemetry from the lander, and from video from robots stationed nearby. If all goes well, a three day visit to make speeches, launch golf balls, etc. If the crewed lander is disabled, the astronauts can return in the spare ascent vehicle. If accident disables both astronauts, the robots should be able to carry them into the ascent vehicle and send them back to Phobos base. Worst case, the robots also remediate any bio-contamination an accident might cause, so that does not spread beyond the landing site.

17) Partial space elevator: A surface-to-beyond-geostationary space elevator requires unobtanium for planets as large as Mars. However, using available engineering materials and 20x taper ratios, an orbiting space elevator hanging Marsward from Phobos can reach down close to the top of the Martian atmosphere, with enough pendulum action to subtract most of the angular velocity. Phobos average orbital velocity is 2138 m/s at 9376 km average radius. Projected to 200 km above the Martian equator (3396 + 200 → 3596 km radius) at Phobos periapsis (9236 km) yields a tether length of 5640 km, an average bottom radius of 3736 km, for an average tip speed of (3736/9376)*2138 m/s → 852 m/s, relative to a Mars equatorial rotation velocity of ( 2π * 3396000m / ( 24.6229 * 3600s ) ) → 241 m/s, for an average relative speed of 611 m/s. That is considerably slower than 5030 m/s escape velocity - a supersonic glider can use that velocity to provide considerable cross-range.

18) Pendulum space elevator: A stronger and cleverly tapered space elevator can be designed to oscillate like a pendulum, rotating at the bottom with additional velocity, actually landing on the Martian surface with zero relative velocity at Phobos periapsis. Martian landers can descend the tether synchronized to the swing, converting forward momentum into more swing, and reach a roll-on/roll-off platform at the bottom. This would obviate the need for rockets, though the descent mechanism must dissipate a lot of heat. A subsequent ascent would be slow and require too much energy.

  • Space elevator note: Megastructure tethers are amusing to contemplete, and may be physically realizable, but they are slow, and cannot access all of Mars beyond a narrow band around the Martian equator. Tether systems may be useful for mature Martian civilization, but they are a time-wasting distraction for Martian mission design. Do the math, and be ready to educate and refocus time-wasting "visionaries", so they do not divide attention and delay deployment of the core mission.


Acknowledgment: The brilliant Dr. Geoffrey Landis at NASA Glenn developed the core principles first, decades ago:

http://www.geoffreylandis.com/Footsteps.pdf Journal of the British Interplanetary Society, Vol. 48, pp. 367-342 (1995) Geoffrey A. Landis, NASA John Glenn Research Center 302-1, 21000 Brookpark Rd., Cleveland, OH 44135

https://doi.org/10.1016/j.actaastro.2006.12.049 Acta Astronautica Volume 62, Issue 1, January 2008, Pages 59-65


Other References:

https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html

PhobosPhirst (last edited 2023-09-10 18:13:53 by KeithLofstrom)