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BS: Space program goals

14 Dec 16 - 02:14 PM (#3826507)
Subject: BS: Space program goals
From: beardedbruce

https://www.wired.com/2016/12/dear-president-trump-heres-make-space-great/

A fairly good piece on goals we should be pursuing in space. I agree with them generally. I have been trying to get the company I work for to start working on the infrastructure to support Lunar and Martian exploration ( supply ships and depots, communication and navigational satellites).

Can we have a reasonable discussion of this, please?


14 Dec 16 - 02:42 PM (#3826518)
Subject: RE: BS: Space program goals
From: Iains

If it gave the military industrial complex a series of essentially pacifist goals to strive for it would be no bad thing.

The US will build the first comprehensive system to defend Earth from hazardous asteroids and comets.
The risk of meteorite impacts has only recently had serious consideration from a few scientists and received little funding. Some argue the Younger Dryas cold period had it's genesis from an impact. Had the 1908 Tunguska event occurred over a major city the death toll would have been horrendous(700 sq miles of forest flattened by a bolide airburst.) The calculated size of tsunamis that could be generated by an oceanic impact is horrendous. Suffice it to say the destruction of coastal nuclear power stations would be one of the minor considerations in the aftermath.
Thus far it is a field of study seriously underfunded and suffering a lack of recognition. No doubt if a strike hit parliament it the funding issue would soon be solved.

For many it is a controversial subject and as yet is not mainstream.

https://en.wikipedia.org/wiki/Holocene_Impact_Working_Group


14 Dec 16 - 02:47 PM (#3826523)
Subject: RE: BS: Space program goals
From: Donuel

If we are going to use gravity tractors we should launch them now.

Not everything in space is profitable, some asteroid gold may be highly radioactive.

The top of the list should be mass deflection (more than magnetic)

After that, warp drive.

Right now some of the best new toys to come are specialized telescopes from the UK. I want one.


14 Dec 16 - 02:49 PM (#3826524)
Subject: RE: BS: Space program goals
From: beardedbruce

Iains,

Agreed on all points. One of the worthwhile goals we SHOULD have been working on from 1970 onward. SKYWATCH ( to identify threats) was never fully funded, and should have been. Nothing has been done to deal with any possible threats ( sort of like Climate Change).


14 Dec 16 - 03:01 PM (#3826530)
Subject: RE: BS: Space program goals
From: beardedbruce

Donuel,

Sorry, any radioactive isotopes of gold would have decayed away, if they are not being produced in the solar system. Where do you think transmutation is happening?

https://en.wikipedia.org/wiki/Isotopes_of_gold

Please note the half-lives- any trace amounts left after 4.5 to 5 billion years would not be a risk.

And we do not (yet) have gravity tractors of warp drives, in any deployable form. I have no problem working on them, but it would be nice to have some means of changing the orbits of bodies that would otherwise collide with the earth ASAP.


14 Dec 16 - 03:45 PM (#3826540)
Subject: RE: BS: Space program goals
From: Donuel

You misunderstand, Gravity tractors can delay or speed up asteroids to miss Earth. Pure research that is not profit driven may enable needed discoveries like deflectors.

You are right, only rogue 'rocks' from another star or system would be risky.

In the way people still don't believe Albert that space can move faster than light, there is a way for black holes to produce/expel elemental matter but while photographed, it is still hypothetical.

Not even mining the moon of isotopes of Helium is not yet cost effective. Making a buck off space is a Trump mindset that sounds good while pure research is one of the harder things to sell to Congress.


14 Dec 16 - 06:29 PM (#3826564)
Subject: RE: BS: Space program goals
From: Donuel

I have a mental picture of a dramatic day on Earth when a less than moon sized body struck the pacific area in a trajectory slightly east to west and up from the equator. BAM the collision sent more material up into orbit that the impact body. The heavier elements in the Earth came up as the molten crater filled in.

The ejecta made a bright fiery ring around the earth and settled down to several spherical bodies and finally into one called the moon. One side of the moon had heavier elements than the other which was subjected to less gravity. Only one size faces earth.

Back on Earth the heavier gold was sloshed up around the east side of the ring of fire. Some in shocked quartz and some all the way to the surface. The ring of fire may be a remnant of the smaller impact object. We have found the moon to be mostly light weight Earth stuff.

How long ago could this have happened? I dunno.

PS it also may have given the earth its seasonable wobble.


14 Dec 16 - 08:50 PM (#3826578)
Subject: RE: BS: Space program goals
From: Rapparee

I'd like to see all of it happen. Nobody ever lost a dime from pure research.


14 Dec 16 - 08:53 PM (#3826579)
Subject: RE: BS: Space program goals
From: Steve Shaw

Some people have been watching too many disaster movies.


15 Dec 16 - 03:56 AM (#3826601)
Subject: RE: BS: Space program goals
From: Iains

Steve the request was for a reasonable discussion. Are you having comprehension problems yet again?


15 Dec 16 - 04:31 AM (#3826606)
Subject: RE: BS: Space program goals
From: Mr Red

The effort to get to Mars with people is going to be a very expensive venture. The Newtonian reality is the energy needed to get peeps and supplies is never going away. And getting them back needs more energy.

Solving the problems of bone loss and muscle atrophy are not small projects. Once you get peeps to Mars could they stand up/walk and do anything useful? If the answer was yes it implies yet more bulk (and energy) to get it all there.

The profligacy here on Earth and global warming may make the will to expend that energy be very politically incorrect. Times and fashions will change when we can't feed the rise in population here.

I suspect that in our lifetime and that of our children, we will be sending machines only.

But if we did try to get people to Mars soon, can I nominate someone who will have little else to conquer when reality bites in 4 years time?


15 Dec 16 - 07:40 AM (#3826627)
Subject: RE: BS: Space program goals
From: Steve Shaw

You have a lot to learn, Iains. Neither you nor Bruce (one of the most unreasonable people you'll ever encounter on an internet forum, by the way) may dictate how a discussion goes. My post was a succinct way of my saying that I think the whole issue of meteorite crashes has been over-dramatised and that disaster movies don't help, over-firing the imaginations of the gullible as they do. I'm sorry if my opinion doesn't match yours. I didn't attack you, yet here you are yet again with your Teribusesque sideswipes at my alleged lack of comprehension. You should be very careful because I won't hesitate to take your rather unfocused and occasionally less-than-literate burblings to pieces and ridicule you in similar vein if you continue. Yours in comradely warmness.


15 Dec 16 - 08:06 AM (#3826628)
Subject: RE: BS: Space program goals
From: beardedbruce

Donuel,

"You misunderstand, Gravity tractors can delay or speed up asteroids to miss Earth. "

I do understand what you mean, but we do NOT have a deployable gravity tractor at this time, nor in the immediate future.


"Pure research that is not profit driven may enable needed discoveries like deflectors."

Agreed.

"Not even mining the moon of isotopes of Helium is not yet cost effective. Making a buck off space is a Trump mindset that sounds good while pure research is one of the harder things to sell to Congress."

Actually, the water found by a program I was on (Clementine/DSPSE) at the south pole of the moon would be cheaper than launching it from earth for lunar colonies/bases and deep-space missions. The potential yield of even a small asteroid in usable metals would be significant, and would be cheaper IN ORBIT than earth-produced by the launch costs ( hopefully going down, by for now a significant amount).


"I have a mental picture of a dramatic day on Earth when a less than moon sized body struck the pacific area in a trajectory slightly east to west and up from the equator. BAM the collision sent more material up into orbit that the impact body. The heavier elements in the Earth came up as the molten crater filled in."

A theory that is making the rounds- but it would have been 3-5.5 billion years ago, when the earth was a lot hotter.

Mr. Shaw,

http://theweek.com/speedreads/667239/nasa-scientist-warns-earth-due-extinctionlevel-event

I will presume you don't bother with accident insurance, either.

Mr. Red,

"The effort to get to Mars with people is going to be a very expensive venture. The Newtonian reality is the energy needed to get peeps and supplies is never going away. And getting them back needs more energy."

It requires energy, but we have the technology today to do it.

"Solving the problems of bone loss and muscle atrophy are not small projects. Once you get peeps to Mars could they stand up/walk and do anything useful? If the answer was yes it implies yet more bulk (and energy) to get it all there."

Currently, a centripetal force base ( centrifuge , spinning spacecraft, or two linked spacecraft tethered together) is the best we can do- but it can be done. We would only need Mars normal gravity, about 1/3 g. ISS has proven that long duration zero gravity can be withstood by appropriate exercise routines.


15 Dec 16 - 08:18 AM (#3826631)
Subject: RE: BS: Space program goals
From: Mrrzy

I like the Star Trek and Known Space universes, but started worrying about the microbiome a while back. Now I worry that they'll get to Mars, but be blind.


15 Dec 16 - 08:26 AM (#3826634)
Subject: RE: BS: Space program goals
From: Steve Shaw

That's just a load of nonsense, Bruce, and you know it. "Overdue" my arse. You know very well that regularity isn't how these things work. Anyway, never mind, as yer man sez we can't do anything about it anyway, except for putting one's head 'twixt one's legs and kissing one's arse goodbye (my addition). I do have accident cover but you can bet your life there's a getout clause for earth-destroying meteorite impacts. "Your claim will be void in the event of everyone being dead."


15 Dec 16 - 08:38 AM (#3826637)
Subject: RE: BS: Space program goals
From: Iains

Steve,
the jury is still out on periodicity.


http://www.americanscientist.org/issues/pub/perturbing-the-oort-cloud


15 Dec 16 - 08:39 AM (#3826638)
Subject: RE: BS: Space program goals
From: beardedbruce

Wrong again, Mr. Shaw.

1. Comets and the Oort cloud are in ORBITS- they are by definition regular.

2. When near collisions in the Oort cloud change the orbits ( by small amounts) the period remains about the same- and many of the objects in the cloud have orbits of about the same period.

3. When a long-term orbit crosses the inner solar system, it is perturbed by the planets. EACH time it comes in, it has a different path
relative to the Earth- and sometimes it WILL collide.

As long as we sit with our heads up our asses, as you and I am sure GregtrF would prefer, you are right- we can't do anything about it anyway, except for putting one's head 'twixt one's legs and kissing one's arse goodbye.

But some of us are aware that we have the means to change the orbits of objects, IF we know what they are and have the desire or need to do so. THAT is why knowing about the possible impacts is important- If we know 15 years BEFORE IMPACT we can possibly avoid "the event of everyone being dead.

Seems like a worthwhile thing to me, but perhaps you would rather be dead.


15 Dec 16 - 08:53 AM (#3826641)
Subject: RE: BS: Space program goals
From: Iains

Steve
Much as I hate to take you out of your comfort zone, I would not want you to be under any illusions as to frequency of impacts. They do happen.

https://en.wikipedia.org/wiki/List_of_impact_craters_on_Earth

That list is not complete by any means.


15 Dec 16 - 09:51 AM (#3826660)
Subject: RE: BS: Space program goals
From: Rapparee

Orbits are predictable, usually needing only two points to compute (although more is better). Observation of two or more points also can give the velocity of the object.

Since the Earth/Moon pair has a known orbit and speed, a point of interaction with another orbit is easy to compute even without a computer program. It's been done using slide rules and even paper and pencil/quill/pen. It's a two dimensional problem, as observation and prediction should be able take into account deviations caused by the gravity of other planets, etc.


15 Dec 16 - 10:02 AM (#3826664)
Subject: RE: BS: Space program goals
From: beardedbruce

Rapparee,

Three points, actually- they are not circular orbits. The problem is in three dimensions: I will gladly take a miss above or below the plane of the planets.


15 Dec 16 - 10:20 AM (#3826666)
Subject: RE: BS: Space program goals
From: Steve Shaw

Not under any illusions, thanks. We have far more urgent matters to worry about. In any case, you never know: a well-aimed meteorite may well take out Trump. As with God, stop worrying about it and enjoy life.


15 Dec 16 - 02:35 PM (#3826720)
Subject: RE: BS: Space program goals
From: Donuel

From the Northern hemisphere look for Orion then draw the line that would follow the path of the sun then make that solar line pass through Orion, now while keeping the intersection with Orion turn the line to the right about 20 degrees.

This is the proposed path that planet X takes way out past part of the Ort cloud.


15 Dec 16 - 03:21 PM (#3826732)
Subject: RE: BS: Space program goals
From: Steve Shaw

Orion's quite big, Donuel...


15 Dec 16 - 05:42 PM (#3826753)
Subject: RE: BS: Space program goals
From: Mr Red

Getting to Mars is expensive. Getting peeps to Mars is way beyond expensive. Expensive in things we will worry about.

In theory we could solve all the problems (eventually), and find the money. In our current world view.

But when the bogeyman that is global warming affects the USA in their pockets, methinks the political climate will change dramatically. And a death or two in striving for an airless planet will nail it for a long, long time.

They fight wars over water now. When food is difficult to grow here on earth, the fight will get worse. Meanwhile the world will be too pre-occupied with defence to address the causes of the global warming/fighting. Going to Mars will be a luxury too far by then IMHO. Don't you think we should fix this planet before fucking up another?

Events in 2016 are only a taster. I make no apologies for playing the TRUMP card. U ain't seen nuffink yet - PAL !


16 Dec 16 - 10:04 AM (#3826870)
Subject: RE: BS: Space program goals
From: beardedbruce

Mr Red,

So, because there were problems in Europe, there should not have been colonists in the Americas?

The development of space-based industries will help deal with some of the problems we have today ( pollution, resources) while probably bringing up other concerns.


16 Dec 16 - 10:19 AM (#3826876)
Subject: RE: BS: Space program goals
From: Iains

unfortunately wars spur technological development, transferring these skills to space industries would create similar advances.


http://www.expertreviews.co.uk/technology/7907/top-inventions-and-technical-innovations-of-world-war-2


16 Dec 16 - 10:31 AM (#3826878)
Subject: RE: BS: Space program goals
From: beardedbruce

Iains,

IMO, the failure to develop technologies that provides more resources and reduces pollution here on Earth will lead to undesirable consequences- Either the living standards or the population will be reduced without them.

Probably by armed conflict.


16 Dec 16 - 11:02 AM (#3826885)
Subject: RE: BS: Space program goals
From: Iains

Bearded Bruce. I think resource wars are already occurring. I do not think the 1990 invasion of Iraq was purely a battle over sand dunes or ideology, or even because of the invasion of Kuwait. If there was no oil there would be no fighting over a bit of arid scrub and desert.
The same applies to the toppling of Gaddafi. The only surprise is that Saudi thus far is immune. This would be nothing to do with huge sales of weaponry to them of course.
   Prior to that Mohammad Mosaddegh was toppled in Iran in the 50's, and of coursepreviously nationalising the Anglo Iranian Oil Company(BP) had nothing to do with his fall either.


16 Dec 16 - 11:17 AM (#3826889)
Subject: RE: BS: Space program goals
From: beardedbruce

" I think resource wars are already occurring."

Agreed that most wars are fought over resources.


But we have yet to dive off the cliff and really start to reduce populations. A new influx of resources from space MIGHT slow this down.


16 Dec 16 - 12:11 PM (#3826902)
Subject: RE: BS:
From: punkfolkrocker

Space program goals... ???

like...errrmmm... Meat and potato pie 'sent into space' from Wigan


16 Dec 16 - 12:59 PM (#3826917)
Subject: RE: BS: Space program goals
From: beardedbruce

punkfolkrocker,

from your clickey:

"The aim is to see if its journey up to 100,000ft (30km) changes the molecular structure of the pie making it quicker to eat. "


"There is no firm boundary where outer space starts. However the Kármán line, at an altitude of 100 km (62 mi) above sea level,[7][8] is conventionally used as the start of outer space in space treaties and for aerospace records keeping. The framework for international space law was established by the Outer Space Treaty, which was passed by the United Nations in 1967. "

So the goal there was not quite space.


16 Dec 16 - 04:40 PM (#3826952)
Subject: RE: BS: Space program goals
From: Steve Shaw

Bollocks, Bruce. That's just pie in the sky and you know it.


16 Dec 16 - 05:12 PM (#3826953)
Subject: RE: BS: Space program goals
From: Greg F.

Not under any illusions, thanks. We have far more urgent matters to worry about.

Ah yes, Steve, but if we concentrated on matters of SUBSTANCE the Trumpists, CowFartBruce and Bubo would be at a serious disadvantage:

All this is further evidence of Trump's genius. He is master of the Art of Disorientation. He's turned Americans into cartoon characters whose heads are always spinning. How the president-elect must laugh at all the fact-based journalism (ghastly tautological phrase) dedicated to disproving things he never believed and can't remember anyway.

The disoriented are more inclined to seek saviors. Trump knows that. Before anyone else, he was onto the way that direct democracy through social media has buried representative democracy.


www.nytimes.com/2016/12/16/opinion/trumps-chinese-foreign-policy.html


17 Dec 16 - 06:01 AM (#3827036)
Subject: RE: BS: Space program goals
From: Mr Red

So, because there were problems in Europe, there should not have been colonists in the Americas?

Some of those problems were direct in causing the emigration. Religious intolerance. If privation was the only driver, then they found more privation in America. Many colonies failed. Death ensued.
And Scotland tried it, bet the farm(s) on it, which bankrupted a lot of people, and precipitated Union.
And America (I am told) has acceptable atmosphere. ;-)

The proverb about giving a starving man in the desert seems to be apt. (other genders are available)

It is not that it couldn't be done, given enough time and effort (and money let it not be forgotten). It is not that a few deaths would stop the project. But Mars has no immediate resources. All would have to be taken. Or machines to manufacture them. Water? at the poles, where the temperature is - er - colder than any part of America.

When the global warming becomes so pressing that we have to deal with it, which takes money. Mars will not be so appealing in that climate (whatever we have by then)...... Mars is not a back-up system for Earth.

Nero seems to spring to mind..................


17 Dec 16 - 06:21 AM (#3827038)
Subject: RE: BS: Space program goals
From: Iains

Mr Red. It is not until Global Warming/Climate Change is in your face(so to speak) that anything positive will be done about it.
But the old maxim "Better late than never" in this case will turn out to be too little, too late, tough S****t!


17 Dec 16 - 09:47 PM (#3827156)
Subject: RE: BS: Space program goals
From: Donuel

Big goals require many little but amazing advances in material science.

Some of the new advances in creating new materials will knock your socks off. I'll mention just one; hydro phobic metal.


17 Dec 16 - 10:54 PM (#3827163)
Subject: RE: BS: Space program goals
From: punkfolkrocker

Metal is supposed to be hard.. not a big soft jessy afraid of water... 😜


18 Dec 16 - 06:30 PM (#3827259)
Subject: RE: BS: Space program goals
From: Donuel

With Hydrophobic metal airplanes would never ice up again.


20 Dec 16 - 09:30 AM (#3827580)
Subject: RE: BS: Space program goals
From: beardedbruce

Mr. Shaw,

"Bollocks, Bruce. That's just pie in the sky and you know it. "


Please tell us how much experience in the space program you have, to make such an observation.

No, it is not bollocks.


We have had the technology since about 1985 to send men to Mars and return them safely. We have the knowledge now, from ISS, to know that this can be done safely, even in zero-gee traveling vehicles.

I can see no reason that the effort to send men to Mars would be a waste of resources- in fact, looking at the spinoffs from the space program, I think that it would be more effective to be going to Mars than any of the present efforts to stop climate change, in terms of efficiency of energy usage and pollution control.


Please tell us how much experience in the space program you have, to make such an observation.


21 Dec 16 - 12:11 PM (#3827794)
Subject: RE: BS: Space program goals
From: beardedbruce

Donual,

Not a lot of water in space. What is there, one would want to capture. Recycling is fine, but there are always some losses.

Cheapest way to terraform Mars would be to take chunks of ice from Saturn's rings and put them into collision orbits with Mars. That, plus an effort to break up the mineral oxcides to get free oxygen,, and we could have a number of good sites to live in (say, in canyons or depressions where the atmospheric density would get up to what people live at in the Andes or Himalayans)


21 Dec 16 - 03:14 PM (#3827829)
Subject: RE: BS: Space program goals
From: Jeri

You know, his name is spelt "DonuEl".

Regarding Mars, I have no doubt we'll end up going there eventually. The logistics of having people live there are mind-boggling to me.


21 Dec 16 - 03:18 PM (#3827830)
Subject: RE: BS: Space program goals
From: beardedbruce

Sorry, Donuel. mea culpa.


22 Dec 16 - 02:18 PM (#3828083)
Subject: RE: BS: Space program goals
From: beardedbruce

Jeri,

Hw different is it to live on the ISS than on Mars?

The ISS is in space, with no atmosphere at all around it, No natural shielding from cosmic rays or solar flares, not resources except what has been shipped up there.

Mars has an atmosphere to protect against cosmic rays, solar flares, and micro meteors. It has physical resources that can be utilized for both construction and supply.

Agreed, it does take a bit longer to get to. Months to Mars vs Hours to the ISS. This means that supplies should be sent first, so they are already in Mars orbit when needed. Not a major problem: Mars has a moon that would be more useful than the ISS for a supply dump (Deimos) and then the time to surface would be similar to the time to orbit for the ISS.


22 Dec 16 - 02:26 PM (#3828085)
Subject: RE: BS: Space program goals
From: beardedbruce

The problem was looked at for the moon

https://www.wired.com/2012/04/one-way-space-man-1962/

The trick is to put the supplies in place BEFORE they are needed- either in orbit or land them on Deimos, or on the martian surface.

They can even be launched is a series so that the manned capsules ( paired, and swinging round a common center to simulate gravity) can pick them up either in Mars orbit, or overtake them enroute.


22 Dec 16 - 02:42 PM (#3828092)
Subject: RE: BS: Space program goals
From: beardedbruce

"At the end of their IAS paper and their Aerospace Engineering article, Cord and Seale explained that the One-Way Space Man concept could be applied throughout the Solar System. When next the concept of a one-way manned space mission was proposed, it was aimed at Mars, and it was envisioned as a truly one-way mission.

At the Case for Mars VI conference in July 1996, George William Herbert of Retro Aerospace proposed dispatching middle-aged scientists on a one-way journey to the Red Planet to cut costs and increase scientific payback. His scenario had the scientists living out their natural lives while exploring the planet to which they had dedicated their careers. Herbert's was a new kind of desperation mission. He and his fellow Mars enthusiasts were not desperate to beat another country to Mars; rather, they were desperate to see humans on Mars."


22 Dec 16 - 03:43 PM (#3828108)
Subject: RE: BS: Space program goals
From: Steve Shaw

Jaysus H. Christ, Bruce, when I said it was pie in the sky I was making a bloody JOKE! Read your own post then read mine of 0440 pm on the 16th immediately following it. Geddit? Pie in space? Pie in the sky?? 😂😂😂


22 Dec 16 - 03:53 PM (#3828110)
Subject: RE: BS: Space program goals
From: Iains

This is no place for levity Mr Shaw, even if it is all pie in the sky to you.


22 Dec 16 - 03:58 PM (#3828113)
Subject: RE: BS: Space program goals
From: Jeri

Bruce, how long does one spend on the ISS and how long would they stay on Mars? Lack of gravity and loss of bone density could be a problem. Also, does Mars get more radiation than Earth? I don't know these things, which is the primary source of the boggle: permanent residency vs a long visit.


22 Dec 16 - 04:00 PM (#3828114)
Subject: RE: BS: Space program goals
From: Steve Shaw

Get it right, Iains. Pie in the sky is levitation, not levity. Tsk.


22 Dec 16 - 04:54 PM (#3828129)
Subject: RE: BS: Space program goals
From: beardedbruce

Mr Shaw,

I was looking at your previous posts to determine your attitude. No humor noticed. Sorry if I missed the connection to punkfolkrocker's post.

Jeri,

ISS missions are on the order of a year. Zero gee the entire time, but regular exercise.

Mars is at 1/3 gee, so that is not a problem with bone loss. However, the transit time is 10-18 months, so some pseudo-gravity by rotation, or spinning two spacecraft around a central point is highly desireable.


22 Dec 16 - 05:20 PM (#3828133)
Subject: RE: BS: Space program goals
From: Steve Shaw

Give over, Bruce. I'm a born comedian. Even Teribus thinks so.


23 Dec 16 - 05:42 AM (#3828200)
Subject: RE: BS: Space program goals
From: Iains

Not levitation Mr Shaw, it was balloon assisted. Maybe hot air was the motive force.


23 Dec 16 - 08:28 AM (#3828239)
Subject: RE: BS: Space program goals
From: Mr Red

It is all a matter of scale. If you were Syrian living in Allepo, the focus is dodging the Russian bombs. Global warming, however concerning, is a minor consideration for them, it will wait.

I don't yet see what technology will come out of sending men or menesses to Mars will contribute to solving the privations of Global Warming.
Terra-forming is all very well on another planet when the only consequence of mistakes is a few human deaths but who is going to risk a different kind of tinkering with the air we breath? Trump maybe - he is stoopid enough to think of it.

I personally think mining asteroids has a better chance of pay-off, once we figure how to keep a lander glued to an irregular surface in virtually zero G.

It is all about profit. However that is measured.


23 Dec 16 - 08:49 AM (#3828242)
Subject: RE: BS: Space program goals
From: beardedbruce

Mr Red,

"It is all about profit. However that is measured. "

As was the exploration and colonization of the Americas, and all the European Empires expansions.




"I personally think mining asteroids has a better chance of pay-off, once we figure how to keep a lander glued to an irregular surface in virtually zero G."

Agreed, in the short term. A new source of resources, not in a gravity well.
Attachment is fairly easy- Magnetic to metallic asteroids, sunken in anchors ( by melting) to the ice and rocky ones.




"I don't yet see what technology will come out of sending men or menesses to Mars will contribute to solving the privations of Global Warming."

Closed loop resource recycling, non-carbon energy production, CO2 utilization for hydroponics... and all the ones we can't see until they are developed.



No need to terra-form Earth- we already have an atmosphere and lots of free water!

But remember, the difference between a self-contained space colony and a star-ship is only propulsion.


23 Dec 16 - 08:51 AM (#3828244)
Subject: RE: BS: Space program goals
From: beardedbruce

Actually, I should have said
"...and all the expansions of any human culture."

Just depends on what the leaders decide is "profit"


23 Dec 16 - 09:21 AM (#3828254)
Subject: RE: BS: Space program goals
From: beardedbruce

An interesting take on space is in Blish's "Cities in Flight" series.


https://en.wikipedia.org/wiki/Cities_in_Flight

Written 55-65 years ago.

"In the period in between the first and second parts, the Cold War ended with the peaceful merging of the East and West blocks into a single, planet-wide Soviet-ruled dictatorship, which hardly made any perceptible change, as the West's political system had already become virtually identical with the Soviet one. However, this dictatorial power was broken by the spindizzy drive which works for very large objects, so that dissidents and malcontents have an easy way of escaping and going off into space. First factories, then eventually whole cities migrate from the economically depressed Earth in search of work; these space-wandering cities are called Okies."


23 Dec 16 - 10:21 AM (#3828266)
Subject: RE: BS: Space program goals
From: beardedbruce

Jeri,

I lost a post

"Also, does Mars get more radiation than Earth? "

Mars gets less solar radiation, being farther from the sun. It has some atmosphere, which will reduce cosmic rays, but not as much as here on Earth. We have a noticable difference between sea-level cities and, say, Denver.

Another reason to land on Mars rather than stay in orbit- one can bury the habitat in that available Martian soil, to provide shielding.


23 Dec 16 - 10:29 AM (#3828269)
Subject: RE: BS: Space program goals
From: Greg F.

It is all about profit.

Its also about weaponization, Mr. Red.


23 Dec 16 - 11:01 AM (#3828276)
Subject: RE: BS: Space program goals
From: Jeri

Thanks Bruce.
Centrifugal force. I wonder why they didn't do that on the ISS. Probably money, engineering and...logistics. That, and they didn't expect people to stay longer than a year. So the rehab they got after returning was enough.

I accidentally watched part of a show on something like the Discovery channel. "Mars". It was a documentary ("mockumentary"?)about how the colony on Mars came to be. Have you seen it?


23 Dec 16 - 11:25 AM (#3828280)
Subject: RE: BS: Space program goals
From: beardedbruce

"Centrifugal force. I wonder why they didn't do that on the ISS. "

Well, the ISS was designed as an Earth Observation system- much of what it does is tied to looking at the Earth. Harder to do if it was spinning. In addition, the structural requirements of a spinning system would have made the solar arrays a LOT more difficult to install and use.

As it is, one can "park" something outside the ISS, and it stays in that relative position. If there were spin on the ISS, each approach would have to be to the central axis, and anything placed outside at any other point would go off at the spin velocity.



Not the Nat Geo special. I have seen the fictional "The Martian", which is not a bad film. Not always scientifically accurate, but that's Hollywood for you.


23 Dec 16 - 01:44 PM (#3828314)
Subject: RE: BS: Space program goals
From: Donuel

Von Braun was heavily invested in centrifugal stations.
The ISS crew is always poised and ready to bug out in the event of an enormous solar event.

Its interesting to point out that women's eyes are a bit more robust than men's eyes in space. There are other differences also.

Evolution in as little as a generation could occur when dormant genes wake up. That may indicate previous exposure to the rarified stress of space travel. Imagine a 50,000 year old adaptation we have no idea we already have. This is all far flung speculation but good filler for sci fi.

What other cool stuff do know Bruce?


23 Dec 16 - 02:10 PM (#3828323)
Subject: RE: BS: Space program goals
From: Greg F.

Vunce der rokets go up, who cares vere dey come down
Dat's not mein department, sez Verner VonBraun.

What's old is new again.


23 Dec 16 - 02:15 PM (#3828324)
Subject: RE: BS: Space program goals
From: beardedbruce

The new Emdrive looks promising, but still developmental- too low a thrust, and no idea how it scales. ion drives are in use now (DAWN)

http://www.space.com/28732-nasa-dawn-spacecraft-ion-propulsion.html
but still low thrust and requires material to eject.

Light sails have the most potential, longer term, IMO. Space based laser systems could provide a decent thrust, or be used for deacceleration.

Linear accelerators /mass drivers are also in development ( one man's railgun is another man's launcher.) Give me a way to impart a speed of 25,000 mph at 120 miles up, in the right direction, and I can put you on the moon.

SNAAP systems ( like the one shown in "The Martian") have been in use, but provide low levels of energy for extremely long periods of time- OK for a coasting spacecraft like Voyager, but not much use for an accelerating platform.


23 Dec 16 - 03:13 PM (#3828333)
Subject: RE: BS: Space program goals
From: beardedbruce

Should have been "SNAP"
System for Nuclear Auxillary Power.

I had the engineering unit of a NIMBUS SNAP power conditioner.

https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator


23 Dec 16 - 05:44 PM (#3828348)
Subject: RE: BS: Space program goals
From: Greg F.

Fascinating as Mr. Spock would say;

Post about the weaponazition of space es desaparacido.

And the Mudcat Junta knows....


27 Dec 16 - 10:39 AM (#3828984)
Subject: RE: BS: Space program goals
From: beardedbruce

Greg,

Weapons in Earth orbit are prohibited, like poison gas is. Did not keep China from testing one on one of their satellites.



On the several SDIO/BMDO programs I have been on, we were only allowed to have sensors in the space segment.


No limits on the moon or beyond, unfortunately. And a dumb rock, in the right trajectory, is a weapon (See Caveman 100).


29 Dec 16 - 12:18 PM (#3829362)
Subject: RE: BS: Space program goals
From: beardedbruce

But if the US does not work on space exploration, others will...


English is the language of international flight- Will Chinese be the one of interplanetary flight?


https://www.yahoo.com/news/china-wants-mars-2020-190121312.html


http://www.newsmax.com/TheWire/china-moon-mars-white/2016/12/28/id/765822/


https://www.yahoo.com/tech/china-going-beat-united-states-back-moon-010043116.html





https://en.wikipedia.org/wiki/Indian_human_spaceflight_programme


http://www.businessinsider.com/japan-is-launching-an-asteroid-mining-space-program-2014-9



http://motherboard.vice.com/read/irans-space-program-may-be-a-cover-for-developing-better-ballistic-missiles



http://spaceref.ca/space-quarterly/military-space-drives-israel-space-program-for-now.html


30 Dec 16 - 08:21 AM (#3829526)
Subject: RE: BS: Space program goals
From: beardedbruce

https://www.yahoo.com/news/nasa-neowise-mission-spies-two-072652143.html


Yet still no systematic effort to identify bodies that might impact the Earth.

6 inches of water rise and slow climactic change over decades- PANIC

2000 foot wave from impact and major climactic change in a few weeks- ho hum, no worries here


30 Dec 16 - 08:32 AM (#3829528)
Subject: RE: BS: Space program goals
From: beardedbruce

http://www.unz.org/Pub/AnalogSF-1966mar-00061

An excellent non-fiction analysis of the problem.


01 Jan 17 - 02:54 PM (#3829871)
Subject: RE: BS: Space program goals
From: David Carter (UK)

Sorry, I must challenge a couple of things that beardedbruce has said. First, there most definitely is a systematic effort to identify bodies which might impact earth, and details are given here and here. The primary discovery facility currently is Pan-STARRS. To date 90% of all NEOs bigger than 1km have been discovered, and they are now pushing to smaller sizes. The thing that will clean the statistics up will be the Large Synoptic Survey Telescope which will be operational from 2021.

Second, Bruce says that "the new Emdrive looks promising, but it doesn't because its complete baloney. This is a proposal by a British engineer, Roger Shawyer, for which he once succeeded in getting a government grant. Its been around for years, and has been debunked by both theory and experiment. Basically it is a tapered microwave resonant cavity, and Shawyer's claim is that thrust can be generated by from the electromagnetic field inside. But it can't, except in miniscule quantities. See articles from Greg Egan here, and from John C. Baez, Professor of Mathematical Physics at the University of California, Riverside, here, here and here.


03 Jan 17 - 08:32 AM (#3830141)
Subject: RE: BS: Space program goals
From: beardedbruce

"The new Emdrive looks promising, but still developmental- too low a thrust, and no idea how it scales."

The jury is still out.

90% is not goofd enough- Not that we are doing nothing, but are we doing ENOUGH?

And NEO misses most of the higher velocity objects.


03 Jan 17 - 10:32 AM (#3830154)
Subject: RE: BS: Space program goals
From: David Carter (UK)

Scales with what Bruce? The reason it has too low a thrust is nothing to do with development, its to do with basic physics as Baez and others explain. You say that the ion drive "requires material to eject", of course it does, anything does. Because of conservation of momentum, anything which generates momentum in a forward direction must also shoot stuff out of the back so that the total momentum is conserved. Stuff can be matter, as it is in any conventional rocket and an ion drive. Or it can be radiation. Photons (including microwaves) carry momentum, and when I heard Shawyer talk about this about a decade ago, photons were carrying the reaction momentum. Photons have a momentum p=E/c, where E is the energy of a photon, and c is the speed of light. But as we know, c is a very big number.

I came away from Shawyer's talk not knowing whether the device wouldn't work at all, or whether it would work, but in order to get an emdrive rocket to take off you would need to put out enough microwaves to cook every living thing for hundreds of miles around.

Fortunately, having subsequently read Egan's and Baez's analyses, its the first.

Don't be fooled by Harold White of Eagleworks either, he has a paper which is claimed to be peer-reviewed, but who peer-reviewed it I don't know because others have subsequently pointed out large holes in the analysis. See here.


03 Jan 17 - 10:41 AM (#3830155)
Subject: RE: BS: Space program goals
From: David Carter (UK)

And no, the searches don't "miss most of the high velocity objects". These things are in elliptical orbits around the sun, and their velocity is determined by Kepler's laws. If they have really high velocity they are on hyperbolic orbits, and nothing to worry about because they are not bound to the solar system. The 10% which havn't been found are either small, or far away. If they are far away it while be a while before they get any closer. But LSST, which has 16 times the collecting area of a single Pan-STARRS telescope, and a survey of much higher cadence, will be good at detecting these. But if you can build an 8 metre wide field telescope plus associated CCD or other detectors and have it ready before 2021, then go right ahead.


03 Jan 17 - 11:16 AM (#3830163)
Subject: RE: BS: Space program goals
From: beardedbruce

High velocity as in coming in from the Oort cloud- Those would not be caught as NEO until they come in- and the first pass might be a collision. IMO a "standing watch" for such objects should be put in place.

As for Emdrive, the amazing thing is not how much thrust it produces, but that it DOES produce ANY thrust ( according to the recent articles in peer reviewed journals.

ANY analysis is only as good as the validity of the assumptions. IF ( and it IS a big if) it produces thrust that cannot be explained by errors, then it should be looked at even if it violates some "law"- after all, when analyzed as a fixed wing design, the bumblebee cannot fly. Perhaps there is something we are not aware of- quantum effects, tunneling, etc.

What we don't know we don't know.


" but in order to get an emdrive rocket to take off you would need to put out enough microwaves to cook every living thing for hundreds of miles around."

From what I presently see, this is correct. but if we want to launch
nanotechnology to another star, the total mass may be reasonable (drive plus payload)

I prefer the idea of a Bussard Ramjet (collect interstellar dust and heat it through a fusion reaction)- but the radiation problem is still there, for a living payload And it seems to work only with LARGE masses- the functional fusion units we have now are called "stars". Makes a nice idea for a trans-galactic trip, though.


03 Jan 17 - 12:49 PM (#3830181)
Subject: RE: BS: Space program goals
From: David Carter (UK)

As for the Emdrive, the amazing thing is that anybody takes it seriously at all. The thrust produced is entirely consistent with a number of sources of systematic error, such as radiation from some component of the experimental apparatus. See here.

It has been true in the past that new physics has resulted from an unexpected experimental result, notably the Michelson-Morley experiment. But far, far more often experimental error is the explanation. As with faster than light neutrinos recently.


04 Jan 17 - 03:24 PM (#3830465)
Subject: RE: BS: Space program goals
From: beardedbruce

But brute force works, too...



http://www.bizjournals.com/losangeles/news/2016/12/30/spacex-unveils-photo-of-falcon-heavy-rocket.html?ana=yahoo&yptr=yahoo

"The rocket's first stage is composed of three Falcon 9 nine-engine cores whose 27 Merlin engines together generate more than 5 million pounds of thrust at liftoff, equal to about 18 747 aircraft. Only the Saturn V moon rocket, last flown in 1973, delivered more payload to orbit.

SpaceX founder Elon Musk has been aiming to build a rocket that will eventually carry people to Mars to form a colony. In September, the billionaire/business mogul said he plans to design a rocket that will take up to 100 people per launch to Mars, with the first flights happening as early as 2023.

"Falcon Heavy was designed from the outset to carry humans into space and restores the possibility of flying missions with crew to the Moon or Mars," SpaceX said on its website."


09 Jan 17 - 06:00 AM (#3831351)
Subject: RE: BS: Space program goals
From: Mr Red

Here's another thing to factor in: space debris.

BBC TV prog "the Trouble with Space Junk" last night (available for 30 days).

Yea Yea, they are cataloging billions (literally) of things down to quite small pieces. & the probability of strikes will be low. But when you are talking human life, the repercussions are such that the stakes are sooooo much higher. Your Marsonauts will pass through this debris field.

And it was clearly stated that the logistics are way beyond current computers to predict all of the relevant bits. (It took 12 months to process 14 months data for the bigger items on several supercomputers around the world). then there is all of the bit on bit strikes that will occur over the years, generating ever smaller, more numerous debris that is still significant. Clean-up is not a viable option yet, by a long chalk.

We better get to Mars within a decade, because by 2100 the debris field will be denser. Smaller bits maybe, but kinetic energy rules!


09 Jan 17 - 07:24 AM (#3831377)
Subject: RE: BS: Space program goals
From: beardedbruce

There are plans in place to send up garbage sweepers to clear out debris from NEO.


http://www.space.com/24895-space-junk-wild-clean-up-concepts.html


09 Jan 17 - 07:29 AM (#3831379)
Subject: RE: BS: Space program goals
From: beardedbruce

and , until recently ( but still under Obama, so no Trump comments please):


https://www.nasa.gov/directorates/spacetech/niac/gregory_space_debris_elimination.html


09 Jan 17 - 07:32 AM (#3831380)
Subject: RE: BS: Space program goals
From: beardedbruce

Space debris is not ignored, but again, are we doing enough?



https://nasasearch.nasa.gov/search?query=space+debris&affiliate=nasa&utf8=%E2%9C%93


09 Jan 17 - 09:41 AM (#3831405)
Subject: RE: BS: Space program goals
From: David Carter (UK)

ESA have a programme on Space Debris, you can read about it here. Their programme includes Analysis and prediction, Scanning & observing, Re-entry and collision avoidance, Mitigating space debris generation, Debris removal, Hypervelocity impacts and protecting spacecraft and International cooperation. And international cooperation certainly includes with NASA. So although it is reasonable to ask "are we doing enough", the professionals at the space agencies who are best placed to answer this are certainly doing a lot of things.


09 Jan 17 - 02:37 PM (#3831505)
Subject: RE: BS: Space program goals
From: beardedbruce

http://www.businessinsider.com/asteroid-flyby-nearer-than-moon-2017-1

"The asteroid, dubbed 2017 AG13, was discovered only Saturday by the University of Arizona's Catalina Sky Survey, according to an email from Slooh, a company that broadcasts live views of space.

It's between 50 and 111 feet (15 to 34 meters) long, and when it swung by Earth, 2017 AG3 was moving at 9.9 miles per second (16 kilometers per second). The near-Earth object, or NEO, came within about half the distance that the moon is from Earth, according to Slooh.

....
Had a porous rock asteroid of 111 feet (34 meters) long hit Earth at a 45-degree angle, the simulator found, it would have exploded as an air burst. The blast would have released about 700 kilotons' worth of energy — dozens of times more powerful than the atomic bomb detonated over Hiroshima."


BTW, the Hiroshima bomb had a yield of 12-18 KT...


09 Jan 17 - 02:49 PM (#3831510)
Subject: RE: BS: Space program goals
From: Steve Shaw

Maybe it would have exploded much higher up. Fireworks rather than firestorm.


09 Jan 17 - 02:54 PM (#3831512)
Subject: RE: BS: Space program goals
From: David Carter (UK)

700 kilotons is a factor 20 less than Castle Bravo though.


09 Jan 17 - 02:58 PM (#3831514)
Subject: RE: BS: Space program goals
From: David Carter (UK)

Plus what Steve said. Tunguska was approximately the same yield equivalent as Castle Bravo, and a third that of Tsar Bomba.


09 Jan 17 - 03:01 PM (#3831516)
Subject: RE: BS: Space program goals
From: David Carter (UK)

And 700 kilotons is marginally more than Chelyabinsk, which was estimated to be 20 metres in diameter. So that is pretty much what we would be looking at if that had hit.


09 Jan 17 - 03:37 PM (#3831522)
Subject: RE: BS: Space program goals
From: Steve Shaw

Not a nuke either. We worry far too much.


09 Jan 17 - 04:07 PM (#3831528)
Subject: RE: BS: Space program goals
From: Iains

The evidence for previous impacts is strong, even if there is a little uncertainty as to exact chronology. These previous impacts occurred in a far less populated and urbanised world. Today increasingly mega cities are situated in the littoral zone and the resulting tsunamis from oceanic impacts would be globally catastrophic. To ignore the very real risk, even if it is low, would be the height of stupidity.

http://elib.sfu-kras.ru/bitstream/handle/2311/1636/03_.pdf;jsessionid=CBA11409F1A8B01C8ADE7E38FDE6754E?sequence=1


09 Jan 17 - 04:49 PM (#3831538)
Subject: RE: BS: Space program goals
From: Steve Shaw

Well thank God my house is half a mile inland and a hundred feet above sea level. I promise to dash down and help the dudes in Widemouth Bay should the Big One arrive. I'll start at the Bay View Inn and progress to the Widemouth Manor. Priorities, Stevieboy!


09 Jan 17 - 05:05 PM (#3831544)
Subject: RE: BS: Space program goals
From: beardedbruce

The wave expected from a major sea impact is many hundreds of feet, and will go tens to hundreds of miles inland.


At 1300 ft above sea level and many hundreds of miles inland, I'll be hunkering down and hoping my shelter will survive. ( underground basement)


09 Jan 17 - 05:48 PM (#3831557)
Subject: RE: BS: Space program goals
From: Iains

The link is quite an old paper and there is, I believe, still dispute as to the height of tsunamis generated by an oceanic impact, and the degree of continental penetration. However the most pessimistic calculations give rise to huge waves so complacency really has no place in the consideration.


http://users.tpg.com.au/users/tps-seti/spacegd7.html#tsunamiimpact


09 Jan 17 - 06:28 PM (#3831568)
Subject: RE: BS: Space program goals
From: Steve Shaw

Yebbut the anatomy of tsunamis does not fit your predictions. The water piles up in narrow confines, not along open coastlines. My house at Widemouth will be fine. I wouldn't be so confident about places in the narrow bits further up the Bristol Channel though. Anyway, I shall continue to enjoy life and worry about far more likely events, such as being run over by a Blackpool tram on my next visit to the Golden Mile, which could be some years off. I think a sea view a hundred feet above sea level in a wide bit is a pretty good compromise.


09 Jan 17 - 07:10 PM (#3831576)
Subject: RE: BS: Space program goals
From: Joe Offer

My understanding about the threat Trump poses to NASA, is that he threatens NASA's authority to study earth science. Earth science has always been a major part of NASA's research, and it has provided much of what we know about greenhouse gases and global warming and other matters that are anathema to some conservatives. The Conquest of Space is one of those "make America great again" things that are so popular with Trump's supporters, but Earth science isn't sexy to them. So, there may be some trouble on that front.

http://www.motherjones.com/environment/2016/12/grinspoon-trump-nasa-inquiring-minds


10 Jan 17 - 03:28 AM (#3831613)
Subject: RE: BS: Space program goals
From: SPB-Cooperator

Pity the goals do not say anything about protecting the well being of the planet we actually live on, its biosphere and humanity? I would not be surprised if Trump already has a business plan to be first in the queue to profit from the commercial opportunities of his proposals.


10 Jan 17 - 04:36 AM (#3831625)
Subject: RE: BS: Space program goals
From: Mr Red

"are we doing enough"

NO

but then the logistics of removing space junk are obvious to paint in broad brush strokes, even if hazy. Big items - you can get at. Not easy but imaginable. Paper thin shards of aluminium and their number cannot be measured currently, and finding them needs a satellite, which itself would become junk if it got it wrong. The concepts are easy, the logistics are not.

That's GPS in the garbage some day. But think laterally, and Electronic Engineers have had this vision for 40 years (trust me I am one, I read the publications): LED street lights - their light can carry data. Adverts & location data. It would pay for itself in urban areas. Rural - always lose out IME. Maybe phone masts will cover that, approximately!


10 Jan 17 - 04:44 AM (#3831627)
Subject: RE: BS: Space program goals
From: David Carter (UK)

Regarding the first link given by iains, what on earth are a group of people at Australian, Welsh and German universities doing publishing in the journal of the Siberian Federal University? My guess is that they couldn't get it published anywhere that we have heard of. That paper proposes that there was an impact of a 1.6km diameter object in 300m of water, in AD1500, just south of New Zealand. Sorry but I think that there would be other evidence for that. A later paper by James Goff et al. dismisses that hypothesis. Unfortunately you can't read any more than the abstract of that paper without paying Elsevier loads of money.

Don't get me wrong, impacts are a threat, and NASA, ESA and others are right to take the measures they are to catalogue the threats, predict possible impacts, and develop mitigation strategies. But in my view the geological hazards are greater, and if I lived on the east coast of Australia it would be Taupo and related volcanos which I would worry about more. Not to mention Toba on Sumatra.


10 Jan 17 - 05:18 AM (#3831633)
Subject: RE: BS: Space program goals
From: Iains

David Carter. What you state is entirely correct. The group do not carry the support of their peers, but that is a lonely furrow ploughed by many others in the past, who have subsequently had their theories accepted. I would not necessarily accept all they say but would certainly keep an open mind and not discount the possibilities outright.
There is a major problem trying to establish any sort of accurate chronology or frequency because oceanic impacts are hard to find and evidence of terrestrial impacts tend to be weathered out in time, also making them hard to find. Just because we have not managed to construct an accurate data base does not give us the confidence to be complacent and say it does not happen. Shoemaker levy's multiple impacts on Jupiter demonstrated very clearly that impacts do occur.
Our problem today is that we have no idea as to frequency, or intensity of possible impacts and as a result of this many do not accept we may have a problem.


10 Jan 17 - 09:11 AM (#3831678)
Subject: RE: BS: Space program goals
From: David Carter (UK)

Its really the frequency of future impacts we need to worry about, not past ones. These may be different for a few reasons, including depletion of the stock of NEOs, the changing character of the atmosphere, and also maybe the increasing distance between earth and moon. The last really large impact (with potential global consequences) appears to have been the Eltanin impact about 2.5 million years ago. So the efforts of NASA, ESA and others to calatlogue potential threats is in my view more important than determining the frequency of past events. Which is as you say hard, because even when you find a circular structure, you are hard pushed to pin down the cause.


10 Jan 17 - 10:43 AM (#3831692)
Subject: RE: BS: Space program goals
From: Iains

The silverpit structure in the north sea is a prime example. Pull apart structure or impact crater? I would agree that the future possibility of impacts is the major consideration - past impacts are merely an academic consideration, although may give some understanding of future events. It would appear that until recent times the possibility of impacts was largely discounted. That is no longer the case, but our knowledge base leaves much to be desired.


10 Jan 17 - 11:48 AM (#3831703)
Subject: RE: BS: Space program goals
From: Iains

Steve you are getting confused between tidal bores and tsunamis. Very different beasts.


https://en.wikipedia.org/wiki/1755_Lisbon_earthquake

The tsunami was widespread and did not restrict itself to narrow channels.


10 Jan 17 - 05:59 PM (#3831782)
Subject: RE: BS: Space program goals
From: Acme

Let's see if this goes through this time:

David Carter (UK) I was able to download the full text of the paper you cited above. If you'll send your email via PM I'll send it to you.


10 Jan 17 - 06:50 PM (#3831788)
Subject: RE: BS: Space program goals
From: Steve Shaw

No confusion this end. Even big tsunamis have very small amplitudes in the open ocean and are generally unnoticed by ships. The wave amplitude and frequency both increase in shallower waters and the effects are far worse still in bays, harbours and in the upper reaches of estuaries where the water piles up. That happened in Lisbon and also in the 1607 Bristol Channel flood. Whether that was a storm surge (the tide was high but the weather was very nice), or, more likely, a tsunami, the effect is just as I described, as you'll see if you look at a map of the areas inundated. Cornwall's north coast (which is where I live) was virtually unaffected, being in the widest part of the Bristol Channel. Upstream, 2000 people drowned. We like to think of ourselves here as being on the ocean's edge, actually. Good surfing but, even miles out, not enough water to submerge Nelson's Column.


11 Jan 17 - 07:38 AM (#3831884)
Subject: RE: BS: Space program goals
From: beardedbruce

Mr Shaw,

So you do not consider the continental shelf to be "shallower water" in relation to the rest of the ocean? The wave hitting the shore would be a LOT larger than you think.


An ocean impact ( 75% probabilty) would be more destructive, and have a larger impact, than a land impact. Great analysis back in the 60s-70's (science fact article in Analog).


11 Jan 17 - 08:53 AM (#3831894)
Subject: RE: BS: Space program goals
From: beardedbruce

Larger impact as in greater effect on climate and more widespread damage.


11 Jan 17 - 09:14 AM (#3831901)
Subject: RE: BS: Space program goals
From: David Carter (UK)

Maybe, Bruce, or maybe not. There is a paper by James Goff et al. on the possible effect of the Eltanin impact on the climate, but its equivocal. As with all of these things, even Chicxulub, there are other factors such as volcanism which need to be taken account of. Its very hard to attribute climate change effects to a single source.


11 Jan 17 - 09:23 AM (#3831904)
Subject: RE: BS: Space program goals
From: beardedbruce

Agreed ( but being done at this time by many here) )

You seem to be looking at trying to account for effects of past impacts- I am concerned with the possible effects of a future impact. If the earthquakes that follow said impact kills off the survivors of the impact, that does not mean we should not be looking at ways of preventing the impact itself.

The effects I am discussing are those that WOULD happen in the event of a major impact. The particulate dispersion into the atmosphere, the tsunami effects, the shock wave, the transfer of heat from the c9ollision can all be calculated and modeled- THEY would have a major effect. There would be other effects not now well modeled- volcanoes, crustal motion, etc, but what we KNOW would happen is enough to worry about


11 Jan 17 - 09:29 AM (#3831906)
Subject: RE: BS: Space program goals
From: Iains

Steve there may be an amplification effect in Bays, but a lot depends on the point of origin of the wave and cause. Recent work below suggests Cornwall would be most vulnerable from a Lisbon type event.
My view is that a lot more theorising and modelling needs to be done to quantify risk - but in the real world there are probably higher priorities that need funding for research.


http://nora.nerc.ac.uk/2767/1/Tsunamis_assessing_the_hazards.pdf


11 Jan 17 - 08:54 PM (#3831996)
Subject: RE: BS: Space program goals
From: Steve Shaw

Well I did a quick shuftie through that lot and found references to one or two-metre waves in western Cornwall. Cor, deadly. Not! Nothing much about our end or further up the Bristol Channel. Mind you, I'm knackered, it's late and I don't feel like wading through the whole of a huge great scientific paper just now and I can't deny I may have missed something. Point me to the relevant bits and we'll get back to it tomorrow.


12 Jan 17 - 08:10 AM (#3832041)
Subject: RE: BS: Space program goals
From: Iains

Steve this will be a bit of a wander unfortunately but I have reduced it as much as I can.
The paper I referred to gave a maximum wave height at the lizard, diminishing as it went towards the Severn Estuary. There would seem to be no records of casualties from the Gwent Levels or Somerset Levels from the Lisbon Tsunami, which would comprise the most vulnerable area especially if surging occurred as you suggested. According to Wiki: " Although there is no record of the overall death toll, the 19th century French writer, Arnold Boscowitz, claimed that "great loss of life and property occurred upon the coasts of Cornwall" I do not see that reported anywhere else. Perhaps the surges occurred during the neap tides. I cannot find a way of reconstructing tide tables that far back, sadly.
There are reports that say the waves were seen as far as Galway and the Thames estuary, as well as damage to the south of Portugal and the other side of the Med.
Conversely the meteorological event of On 30 January 1607, around noon, the coasts of Bristol Channel suffered from unexpectedly high floodings that broke the coastal defences in several places. Low-lying places in Devon, Somerset, Gloucestershire, and South Wales were flooded. The devastation was particularly severe on the Welsh side, extending from Laugharne in Carmarthenshire to above Chepstow in Monmouthshire. Cardiff was the most badly affected town, with the foundations of St Mary's Church destroyed.[1]

Floods resulted in the drowning of an estimated 2,000 or more people, with houses and villages swept away, an estimated 200 square miles (51,800 ha) of farmland inundated and livestock destroyed,] wrecking the local economy along the coasts of the Bristol Channel and Severn Estuary.

The coast of Devon and the Somerset Levels as far inland as Glastonbury Tor, 14 miles (23 km) from the coast, were also affected. The sea wall at Burnham-on-Sea gave way, and the water flowed over the low lying levels and moors. Thirty villages in Somerset were affected, including Brean which was "swallowed up" and where seven out of the nine houses were destroyed with 26 of the inhabitants dying. For ten days the Church of All Saints at Kingston Seymour, near Weston-super-Mare, was filled with water to a depth of 5 feet (1.5 m). A chiselled mark remains showing that the maximum height of the water was 7.74 metres above sea level.(courtesy Wiki)

To give this additional perspective:The Severn Estuary is dominated by tidal processes. It has the second highest tides in the world, with an average mean tidal range of 6.5m at neaps and 12.3m on springs. . Tidal range increases further up the estuary, and high spring tides reach as far as Tewkesbury when river flows are low . The Estuary's high tidal range is caused by a combination of factors: an uninterrupted tidal setting for North Atlantic tidal wave propagation, amplification of the wave as it is constrained and converges in the Estuary, and a resonance effect due to its distance from the Atlantic amphidrome . The tidal curve is complicated by geomorphological constrictions and the partial impoundment of the ebb spring tide by the flood spring tide.
Severn bore
Large spring tides commonly lead to the formation of a tidal bore The Severn Estuary is particularly vulnerable to surges because of its orientation and due to its topography and coastal configuration. There is debate over where on the Estuary is most exposed to surges. It may be that the surge level builds as it travels up the estuary and thus threatens the upper reaches more, or that the surge amplitude reduces as water spills out onto the floodplain as it travels, thus affecting the lower reaches more. Thanks to the Severn Estuary's massive tidal range, only extremely large surges or those that occur near high tide have the potential to cause flooding. For example, even a 3m surge would not exceed the mean high water level if it occurred at low or mid tide. The largest recorded surge event on the Severn Estuary was a positive surge of 3.54m, recorded in March 1947 at Avonmouth, but fortunately it occurred at low water on a neap tide,so large scale flooding did not occur .. This was a far larger surge than the 1.45m surge of 1981, which occurred closer to high tide and caused extensive flooding along the north Somerset coast.
Storms
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The Severn Estuary is particularly vulnerable to Atlantic storms because of its topography and coastal configuration, orientation with respect to prevailing winds, and tidal setting, which together enhance surge heights from storms tracking east and north eastward .

If the event of 1607 was a Tsunami rather than a meteorolgical event several things do not make sense.
The effect was very localised. This surely rules out Tsunami. The reported casualty rate was very high but there are no reports of damage elsewhere, or casualties. This strongly suggests a storm surge.
The Lisbon earthquake created damage on a continental scale(at least)
yet the effects were far more subdued than the event of 1607, that was both localised and of far greater severity.
   My conclusion is that as it stands there are too many assumptions and a woeful inadaquacy of hard data. I would say in conclusion that since the Storegga Slide storm surges have presented the UK with a far greater risk than tsunamis.


17 Jan 17 - 04:42 PM (#3833232)
Subject: RE: BS: Space program goals
From: beardedbruce

http://www.sfgate.com/news/science-environment/article/NASA-to-explore-asteroid-made-of-10-000-10860219.php?ipid=articlerecirc&c

"Death Star in NASA image

Enticingly, the mission's lead scientist has put a price tag of $10,000 quadrillion on the asteroid, known as "16 Psyche.""


World GDP is about $74 trillion. This rock represents 135,000 years of GDP


18 Jan 17 - 04:33 PM (#3833430)
Subject: RE: BS: Space program goals
From: beardedbruce

http://www.cnn.com/2017/01/18/health/space-junk-2017-cassini/index.html


More on the topic of dealing with space debris.