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Announcement: This forum is accepting new registrations by emailing newmarsmember * gmail.com become a registered member. Read the Recruiting expertise for NewMars Forum topic in Meta New Mars for other information for this process.

#76 2021-01-17 14:55:38

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,190

Re: Recruiting expertise for NewMars Forum topics:

What I was talking about was the accounts of spammers not banned that still had a chance to request a new password as they are not locked out until banned or to use there existing ones to get in an cause trouble of which the example was from the other day since we can not camp out on the home page looking for them to use there login to close the barn door....
Currently I am in page 4 alphabetically banning to remove the back door...

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#77 2021-01-18 08:55:01

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut ... Daily report ... We have received new correspondence:

For (candidate),Thank you for your message!  It is kind of you to offer to help with our project.I will post your message in the Recruiting topic, and invite members to consider your application.
***
We have a Medical Doctor in the group ... Quaoar from Italy.... A medical practice will be essential in Mars settlement.  
***
The procedure to bring a new member into the group is still being worked out ... we have two new members admitted since the Administrator closed registration due to the thousands of spam ID's we have received.
***First I will wait for approval from the members. That will take a day or two.Then I will ask you for the name you would like to use for the account.I will modify one of the spam accounts for you to use.I will send an email from the new account to you at the address you provided above.This will confirm that I have entered the email correctly.You will not be able to login, because the spammer password is still stored for the account.
***
Just ask FluxBB (the forum) to send you a replacement password.If all goes well, you will receive the temporary password.
Log in, and immediately change the password to what you prefer.
Post a message so we can know you were successful!
Write me here if you do not receive the test email, or if any other problem occurs.***Thank you again for your message!(th)

On Mon, Jan 18, 2021 at 5:51 AM (candidate) wrote:
Hello there! I would want to join you in a nice conversation about Mars. I have been part of the talks and great conversations about space travel and making all the dreams of going to space to become a reality than just simply drawings. I have expertise in Medicine, and still studying at this point, but I already engaged myself to an even bigger conversation and planning about Mars with you guys.

All currently Registered Members are invited to comment upon this application.

I'll need approval from SpaceNut and kbd512 (for kbd512 .... I'll give you additional time due to your work schedule)

For kbd512 ... would you like for me to pose the same question for this candidate?

We can make that part of the standard procedure.

For SpaceNut ... would you like for me to pose the same question you asked CaptJT ???

We can make that part of the standard procedure.

This is our third new member application in the new By-Invitation Registration procedure.  We are still working out the kinks.

(th)

Last edited by NewMarsMember (2021-01-18 08:57:05)


Recruiting High Value members for NewMars.com/forums, in association with the Mars Society

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#78 2021-01-18 09:11:54

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,190

Re: Recruiting expertise for NewMars Forum topics:

Sure as it would continue to gather how to get interest. Since the checks and balance is in the promotion invite that I have posted in a place that requires registration as well indicated spammers are not welcome.

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#79 2021-01-18 09:57:43

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut re #78

Thanks for confirmation you'd like to have the question given to the new application as a routine part of the admission procedure.

SearchTerm:Checklist Draft of checklist for admitting new members

Here is a draft of a checklist for our new candidate (and by extension for all future candidates):

1) Receive application on NewMarsMember @ gmail.com
2) Reply confirming receipt - include standard procedure (this does not yet exist but is in development)
3) In the present instance, we have an application from a medical student who may be interested in a practice on Mars (yet to be confirmed)
4) Todo: send question from SpaceNut <<== Sent 2021/01/19 (about how found site)
5) Todo: send question from kbd512 <<== (about interest in Mars exploration)
6) Watch for reply from candidate

SearchTerm:Questions for candidates for admission to forum

SpaceNut:

kbd512:

(above to be filled in later after ID recovery)

Edit#1: It appears we may be evolving a (simple) essay form of candidate evaluation.

(th)

Last edited by tahanson43206 (2021-01-19 10:09:51)

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#80 2021-01-19 09:55:10

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut re New Members ... there was no new incoming correspondence...

I sent your question to the latest applicant:

Hi! Hoping all is well!
This is the question from SpaceNut:So how did the applicant hear about this out reach would be interesting to know?
I'll post your reply.As indicated recently, Please send the name you'd like to use on the forum.You can see our newest member's reply by searching for CaptJT*
The * at the end gives you all the accounts that begin with those letters.

I'm hoping you might be interested in thinking about setting up a medical practice on Mars.
If you want to get a sense of what teams are thinking about the future on Mars, you can watch three recent videos (near 40) which report results from last year's Mars Conference competition.
Look for Mars Conference 2020.

(th)

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#81 2021-01-20 08:04:08

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

In a recent post, RobertDyck has identified a specialization to add to the NewMars Recruiting effort:

http://newmars.com/forums/viewtopic.php … 48#p176048

In this topic, RobertDyck has opened the door for someone with knowledge of human nutrition to assist with planning menus for the Large Ship.

If you (a reader of this post not already a member of the forum) know of someone who might qualify for the position (on a pro bono basis) please let them know.

You (or they) can reach us at NewMarsMember * gmail.com

In a related concern, this is a good time to remind everyone that humans evolved on Earth to take in potable water loaded with minerals taken up by rain water as it meanders through rocky soil.  A volume of pure water is NOT good to drink, although (I'll admit) fresh rain water comes pretty close.

Pure water is a solvent.  An anecdote I remember (for some reason) is that when a wrench fell into a pool of pure water in a cosmic ray detection facility in Canada, it dissolved.

(th)

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#82 2021-01-20 10:13:25

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut re Daily report ... We have no new incoming correspondence.

We are standing by for inquiries or applications for membership.  We (for sure I) are/am looking for people who are likely to be among the folks who will be in the first major wave of explorer/settlers who follow the initial exploration phase.

The ideal candidates will be those who think they might be job creators/leaders .... The world is populated with billions of job holders. The number of job creators is small.  All those folks who are willing to hold jobs are waiting for job creators to come along, to take all the risks of starting new ventures.

My hope is that the NewMars forum will become a place for future job creators to meet and coordinate their efforts.

The My Hacienda topic in this forum provides a framework upon which to build.

(th)

Last edited by NewMarsMember (2021-01-20 10:14:09)


Recruiting High Value members for NewMars.com/forums, in association with the Mars Society

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#83 2021-01-20 11:12:45

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

Help Wanted ....

The recent suggestion by Void, to deliver selected payloads to Mars using ballistic delivery mechanisms, resulted in creation of a topic to develop the idea.

Given encouragement by members of the forum, and [Dayton Engineer], I am adding a new position to the Volunteer Recruiting lineup.

The assistance needed is to accumulate the knowledge needed to safely deliver ballistic payloads to Mars, to assemble the needed human players, and to organize activities leading to creation of a successful business.

Since costs of delivery of payloads to Mars using ballistic techniques will be less than delivery by any soft landing method, and since the speed of delivery is dramatically increased, this business model will be highly competitive with any other that might be imagined, short of a Startrek Transporter.

The downside expense arises from the fact the delivered payloads will be buried in the regolith where they came to rest, so a robust mining/recovery enterprise will be needed as part of the package.

In a previous post in this topic, Calliban has shown some possible designs for a receiving system on Mars that will dissipate kinetic energy safely in the regolith, without losing cargo or causing ejection of material into the atmosphere of Mars.

If someone is interested in this position, or in any related volunteer position, please write NewMarsMember * gmail.com.

Edit#1: Earlier in this topic [Dayton Engineer] has shown that electronics is capable of withstanding acceleration on the order of 20,000 G's, and that was before solid state devices became available.  It would be worth study to see if the deceleration forces of the proposed supplies delivery mechanism can be kept at or under 20,000 G's.

(th)

Last edited by tahanson43206 (2021-01-20 11:16:52)

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#84 2021-01-21 06:47:47

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut re New Members ... there was no new incoming correspondence...

Temperature at the beach in Naples is 52 degrees Fahrenheit
There are several bundled up people on the pier and a couple on the beach. It is 7:42 AM there.
The sea is calm. The sunrise is reflected in reddish tinges in the clouds in the distance over the Gulf of Mexico.

Live feeds of scenes like these might be welcome for residents living on Mars. 

(th)


Recruiting High Value members for NewMars.com/forums, in association with the Mars Society

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#85 2021-01-21 10:06:19

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

This post is intended to serve as a reference point for candidates for admission to the NewMars forum, and for those working the email entry portal.

SpaceNut provided this question: So how did the applicant hear about this out reach would be interesting to know?

kbd512 provided this question: Yes, I'd like the candidate to briefly explain his personal interest in Mars exploration.

The procedure that seems to be evolving is for the candidate to provide a short essay answer to both questions.

The response will be posted on the site in the Recruiting topic.  After a suitable period of time for evaluation, the candidate will be admitted or provided feedback on how to prepare for another try.

SearchTerm:Procedure for admission of new members
SearchTerm:Questions for essay response by new member candidates

Regarding the rate of admission .... the rate of admission of new members is likely to be modest, and comparable to the rate of hires of new employees at a small business.  The forum has a large population of members already, so new members can be brought in with personal attention.  An application process may take several days or a week or more.  The kind of person who is needed right now is someone who is interested in a lengthy engagement, and achievement of one or more personal goals, or assistance to an existing member who has an ambitious goal that needs specific skills to advance.

For those still interested in starting the process, the entry portal is NewMarsMember * gmail.com

The portal is opened once per Earth day.

(th)

Last edited by tahanson43206 (2021-01-21 10:13:11)

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#86 2021-01-21 18:42:15

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,190

Re: Recruiting expertise for NewMars Forum topics:

NewMarsMember wrote:

For SpaceNut re New Members ... there was no new incoming correspondence...

Temperature at the beach in Naples is 52 degrees Fahrenheit
There are several bundled up people on the pier and a couple on the beach. It is 7:42 AM there.
The sea is calm. The sunrise is reflected in reddish tinges in the clouds in the distance over the Gulf of Mexico.

Live feeds of scenes like these might be welcome for residents living on Mars. 

(th)

Yes the slow glass topic....

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#87 2021-01-22 06:43:43

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut re #86

Thanks for the reminder of the Slow Glass topic!

We may have a lot of days with no activity on the NewMarsForum * gmail.com portal.  Activity there is likely to be directly related to the amount of outreach we attempt, and if you and I are the only ones working, then the amount of outreach is going to be limited to the amount of time we have, and the ideas we come up with for placing the message of opportunity where it might be read.

The Naples Pier webcam is as good a resource as any to provide a substitute report where there is no new activity at the portal.

Today, January 22nd, the air temperature is 52 degrees at 7:41 AM.  The sea is calm.  Workmen are tending to the pier.  A few guests are meandering about on the pier and the beach below.  The sky over the Gulf of Mexico has a sunrise glow.

***
Speaking of recruiting ... I watched Video 42 yesterday ... it is a one hour report on the Mars Rover challenge competition, which has been an annual event since 2007 (if I recall the starting year correctly).  There were 93 entries for the event this past year, but it was called off due to COVID.

The young people (and their advisors) come from all over the world, and the teams have progressed in their designs from a simple little four wheeled go-cart like rover to something that could show up in a NASA video.  Teams have experimented with numbers of wheels, from three to six.

The judges and the planning committee have ** really ** taken advantage of the Mars Desert Research Station site to provide Mars Analogue challenges.

The test that (apparently) has not yet been successfully passed is the Lander test.  This is a mockup of a lander that the team must deal with despite it having been designed for access by a human.  Teams have struggled with the tasks required.  My guess is that they will succeed in coming years.

(th)

Last edited by tahanson43206 (2021-01-22 06:51:11)

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#88 2021-01-27 08:27:49

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

The Knowledge Forum was created by Dr. Lewis Dartnell some years ago.  I have been a member there for some time, and Terraformer recently gained admission through personal intervention by Dr. Dartnell.  It was Terraformer who invited me to try out here at the NewMars forum.

I wrote a post asking for permission from Dr. Dartnell, and (hoping permission will be granted) I posted the following announcement on the Knowledge Forum.

The Knowledge Forum, like this one, is regularly visited by search engines, so perhaps someone in the (very small) population of interest will see it.

The NewMars forum is a project of the Mars Society.

A member of the NewMars forum is a long time Mars Society member from Canada.  He has undertaken design of a large rotating space vessel, capable of holding 1000 passengers and 60 crew for flights between Earth and Mars. 

There are currently two openings for volunteer support of the Large Ship venture ...

The first is a request for an experienced chef, to assist in planning supplies, menus,  equipment, staffing and management of an operation supporting 1000 passengers and 60 crew for up to two years.

A flight to Mars is planned to take under six months, but in case of a problem the ship can return to Earth on a well designed elliptical trajectory in a total elapsed time of two years.  The launch from Earth must be assumed to last for two years without resupply.  If all goes well, the ship will "dock" near Mars in under six months, and then return to Earth at a later time.

The second opportunity is for a mission trajectory planner ... One of the PhD level members of the forum is an experienced aerospace engineer, but he is a master of computing tools that were state-of-the-art in the 1970's. It would be helpful if someone with experience in planning missions for spacecraft travelling to Mars or other Solar System destinations, and with the appropriate software tools at hand, were to assist with planning flights of the Large Ship. 

One of many challenges before the mission trajectory planning team is trying to find a solution that allows the Large Ship to "dock" (go into orbit) at Mars without a large expenditure of mass and energy, or without having to take the enormously risky path of trying to fly a passenger ship through the thin atmosphere of Mars to slow down.

While the project architect is willing to take that risk, there may be a trajectory solution that provides for meeting all the other objectives of the flight plan without a pass through the atmosphere.

(th)

Last edited by tahanson43206 (2021-01-27 08:41:59)

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#89 2021-01-27 21:02:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,190

Re: Recruiting expertise for NewMars Forum topics:

Posted to the Mars society members area in Mission design :
With any mission to Mars it will take more than a fancy ship and engineers when we get a ship built on orbit that can loop from LEO to LMO with more than just a few hundred making the trip. Newmars has been working on a large rotating ship to carry 1000 passengers and 60 crew to Mars. So we are going to need Cooks and Chefs to make the meals for the masses to eat along with nutritionist and dieticians.
We are looking for real life experience to aid this project on its way towards a reality.

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#90 2021-01-27 21:54:44

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut re #89

Thanks very much for this outreach effort! 

Changing the subject slightly ... you may easily have missed seeing the video by Dr. Geoffrey Landis on the precursor to MoXiE.  There isn't time enough in the day or even the week to do more than a fraction of the things we might find interesting.

Never-the-less ... I'm hoping you can squeeze it in ... it's not the talk I'm pointing out, although that is worth while for engineers or scientists who might be interested in the subject ... instead, I'm pointing out the remarkable circumstances of the home based presentation, which are only possible due to the pandemic.

Dr. Landis is a favorite with a great number of people, for his science work of course, but also for his willingness to appear as a panelist in countless conventions, and for his science fiction in addition to his scientific writing, some of which is intended for the general public.

I'd appreciate your considering the question of whether Dr. Landis might be willing to think about the needs of cats in a habitat on Mars, or on a Large Ship going to Mars.

(th)

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#91 2021-02-03 08:46:16

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut and GW Johnson ...

The NewMarsMember * gmail.com account had a message this morning!

GW Johnson
Feb 2, 2021, 11:23 PM (10 hours ago)
to NewMarsMember

This is a test intended for someone I know as "Tahanson43206".  I am the one he knows as "GW".  If it gets through,  please reply so that I know I have the right address.  Then I can send the promised files.

GW


TaHanson43206
9:34 AM (0 minutes ago)
to Gary

Yes, you got it right. Hi Dr. Johnson! Thanks for sending this test message!
I'm looking forward to seeing the spreadsheet.
I hope to be able to explore it in detail.
Calliban in particular seems to be receptive to moving from conceptual outlines of activity to something with a bit more substance.
(th)

Since we are in the Recruiting topic, I'd like to take this opportunity to remind all current, active, Registered members that they can help by publishing our Help Wanted Volunteer Opportunities in the local newspaper or other media that might be able to reach folks who are among the thousands alive today who will be in the first waves of Mars settlers.

(th)


Recruiting High Value members for NewMars.com/forums, in association with the Mars Society

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#92 2021-02-04 11:34:44

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut ... this is the report for NewMarsMember * gmail.com

A pair of emails and a pair of files arrived from GW Johnson.  I'd like to invite you to start thinking about how we can turn this gift into a tutorial that will have lasting value.  Ideally we would have a permanent repository managed by Mars Society, but in the absence of any indication that is possible, we can/should look at other options.

To begin with, we can make a topic dedicated as a tutorial, and connected to the primary Orbital Mechanics topic.

Here is my reply to Dr. Johnson:

Hi Dr. Johnson,
The files arrived and appear to be intact!  I only check this email box once a day, around Noon.
I'm looking forward to (hopefully) following through this time. Thanks for including the documentation!
(th)
On Wed, Feb 3, 2021 at 11:38 PM GW Johnson wrote:
Just wondering if you successfully got the files I sent.
GW

(th)

Last edited by NewMarsMember (2021-02-04 11:36:12)


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#93 2021-02-04 18:00:43

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,190

Re: Recruiting expertise for NewMars Forum topics:

Have sent an email to James with regards to our interest which was also earlier request along the same lines last year with regards to a repository for knowledge to be saved in other than this forum.

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#94 2021-02-06 10:02:57

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

This is for SpaceNut (primarily) and certainly for those who may be interested ...

The NewMarsMember * gmail.com account received another gift package from GW Johnson.

This one included additional spreadsheets and documentation, selected in expectation they will be useful to NewMars members.

Here is part of my reply ...

Hi Dr. Johnson,The four new files arrived safely.I sent them on to my personal email account immediately. <snip> I define success (in this case) as creating a tutorial that can be taken in a step-by-step fashion, using your spreadsheet, and now (multiple spreadsheets) as the framework.<snip> Your work can be represented in advanced technology, if we can enlist volunteers to cause that to happen.***What I would ask you to do is to join me in the forum, in conversation with SpaceNut about how we can build the kind of tutorial repository of knowledge I'm trying to describe.(th)

For SpaceNut ... if I understand your correspondence with Mr. Burk correctly, he is trusting you (and your support team) to manage the forum as well as he would do if he had time to spend on it, which he clearly does not. 

In the initiative with Dr. Johnson, we have an opportunity to develop an educational component to the forum, while retaining all the creative thinking that has become a major value of the forum over 20+ years.

I am proposing that we create two new topics in association with the existing Orbital Mechanics topic ... One would be a tutorial, and the other would be a freeform topic next to it, which i am currently describing as a Peanut Gallery.  Another term would be fine if you prefer one.

(th)

Last edited by NewMarsMember (2021-02-06 10:04:33)


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#95 2021-02-07 10:52:44

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut ... report for NewMarsMember * gmail.com

One message arrived... this was in reply to an inquiry about programming Chrome to perform POST commands as well as GET.

Re: 20210206 Inquiry Marc Rochkind Programming Chrome Apps follow up POST
Inbox

OReilly Media <noreply@oreilly.com>
Sat, Feb 6, 1:13 PM (22 hours ago)
to me

Thank you for reaching out!

We have received your message and will respond soon. Meanwhile, we have created case number 01308073 for your reference. If you need to follow up with us on the same issue, please click here to email us.

Thank you again for reaching out and we look forward to working with you to resolve the issue or request.

Best regards,
Your O'Reilly Media Customer Support Team

This email has been sent from an unmonitored account. Please do not reply.

(th)


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#96 2021-02-08 11:36:55

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut .... another spreadsheet arrived from GW Johnson!

This one is self-documented.  It includes the capability of setting up three burns:

1) Launch (I would assume (but don't know yet)) the "launch" is from LEO.
2) Mid-course correction
3) Landing (this could (I presume)) be a burn to achieve orbit around a destination body

SpaceNut ... at some point, I'm hoping members of this forum will be interested in the idea of converting this body of work into a tutorial for a young person with the appropriate abilities and a basic education to achieve the ability to plan a mission.

It has been demonstrated that a combination of college level studies and on-the-job training (at NASA for example) can deliver a person able to perform mission planning.

In the Internet age, we have the opportunity to develop a currculum that allows a student anywhere in the world to achieve the skills necessary to successfully plan a mission.  In just a few years, it will be possible for individuals to find employment navigating vessels between Earth and Mars (and no doubt other destination).

(th)


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#97 2021-02-08 17:05:24

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,548
Website

Re: Recruiting expertise for NewMars Forum topics:

TH:

Of course you can use the rocket vehicle performance spreadsheet for any stage doing any sequence of burns,  up to 3 burns!  If you have less than 3,  input the dV into the burn or burns that you do make,  as dV values for burns 1 (and 2 as appropriate).  Input a zero dV and any dummy engine values for burn 3 (and for 2 if that dV is also 0).

For vertical launch from Earth with a clean slender vehicle,  I usually factor the first stage burn by 1 plus .05 for drag loss plus .05 for gravity loss.  The second stage of a two-stage vehicle is usually exoatmospheric and very nearly horizontal,  so its portion need not be factored,  or at most only about 1.02 for gravity loss.

For those analyses that don't suffer from being a tad cruder,  I usually apply the 1+.05+.05 factors to the surface circular orbit velocity,  for launch from Earth,  and unfactored (factor = 1.000) for departure from orbit.  The surface circular velocity is higher than circular at orbit altitude,  by precisely the potential energy of going to that altitude. 

For Mars,  I reduce the gravity factor with Mars surface gee:  .05*.384,  and the drag factor with Mars's relative surface density:  .05*.007. Similarly,  for launch from the moon,  I reduce the gravity factor by the moon's surface gee:  .05*.165,  and zero-out the drag factor.

For propulsive landing burns,  the ideal dV is just the speed at which you finally approach the surface.  It needs a whopping factor applied to it,  to reflect any hover or divert or other maneuvering you need to do in order to avoid landing obstacles,  or to correct being off-course.  I have been using factor 1.5,  but factor 2 is not unreasonable. 

I took a closer look at the two demo Starship examples in the spreadsheet,  and increased them to four examples.  I "upped" the required vertical gee capability at landing from 0.5 to 0.7 gees net,  just because Spacex has been having landing problems with SN-8 and SN-9. 

For the average Hohmann transfer,  I'm showing 353 metric tons of payload deliverable to Mars,  with nearly-dry tanks at landing,  and a full-capacity 1200 metric ton propellant load aboard at departure from low Earth orbit.  That's an 8.6 month trip,  one-way. 

If you go to the faster 2-year abort trajectory,  you get there in 4.3 months one way.  Under the same dry-tanks landing and full-capacity propellant load conditions,  you can deliver 248 metric tons of payload to Mars. 

Those require something like 6-8,  maybe 9 tankers to refill to full capacity in LEO.  Spacex has never shown that many tankers on its website presentations,  so I looked at a nominal 150 metric ton payload to Mars,  and the min propellant loadout in LEO to deliver it. 

For the 8.6 month average Hohmann trip,  150 tons payload required only 686 tons of propellant out of a 1200 ton capacity.  For the 4.3 month trip on the fast trajectory,  that same 150 ton payload delivery required 879 metric tons of propellant be aboard at LEO departure.  Bear in mind that the ship is supposed to arrive in LEO with the allowance for deorbit and landing still aboard.  Something on the order of 50 tons.  Maybe less.

I was surprised and pleased by those greatly-reduced propellant loadout numbers.  Instead of 6-8,  maybe 9 tankers,  we are looking at 3-4,  maybe 5 tankers.  That is remarkable,  and I believe it is why Spacex has been showing the on-orbit refilling representations that it has.

This kind of reverse-engineering is not new to me.  Decades ago,  I did some pretty similar analyses reverse-engineering the Russian SA-6 surface-to-air missile.  I and 3 propellant chemists also reverse-engineered their ramjet fuel propellant,  right down to the level of their quality control on the process.

If Moshe Gill is still alive in Israel,  he and I are the only two westerners left alive who know how to make that stuff at production readiness. The other 2 chemists died many years ago.

GW

Last edited by GW Johnson (2021-02-08 17:06:57)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#98 2021-02-13 10:16:56

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,872

Re: Recruiting expertise for NewMars Forum topics:

In a post in Ballistic Delivery, Calliban recently noted the opportunity for a Mechanical Engineer, or a student aiming for a degree in the field, to assist with details of working out a business for the Earth-to-Mars trade.  The concept arises from an idea of Void, to see if ballistic delivery of supplies to Mars makes sense.

With advice and counsel from GW Johnson and others, Calliban has identified a window of opportunity for delivery of selected high value supplies to future Mars settlers by employing only the deceleration capability of the thin Mars atmosphere, and the properties of the Regolith to accept a well designed package.

All current NewMars forum members are welcome to nominate candidates in this topic.

In addition, current NewMars forum members are welcome to identify candidates in their circle of acquaintances, and invite them to write to NewMarsMember * gmail.com to inquire about admission to the forum.

As a reminder (since the forum architecture has no permanent storage at present) the procedure for admission to the forum is now By-Invitation-Only.

Applications are requested to provide two short essay-like responses to the questions:

From SpaceNut: How did you find out about the forum?
From kbd512: How would you like to help the forum?

Responses will be posted here (in this topic) for evaluation by the Administrators, Moderators and members.

Upon acceptance, the candidate will be offered one of the Recovered ID's previously created by spammers, and re-purposed for ** real ** persons.

(th)

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#99 2021-02-14 07:36:44

NewMarsMember
Member
Registered: 2019-02-17
Posts: 1,303

Re: Recruiting expertise for NewMars Forum topics:

For SpaceNut ... there is no new correspondence at NewMarsMember * gmail.com this morning.

Open requisitions for assistance include:

Master Chef to advise RobertDyck in design of Large Ship ... will be experienced in large vessel food service planning and supervision

Mechanical Engineer (or student working on engineering degree) to help with design of Ballistic Cargo delivery system for Mars (Calliban)

Other needs include:

Assistance with planning development of the work of GW Johnson into an educational curriculum to carry a student from beginner to able to navigate a spacecraft between Earth and Mars and back safely.

Assistance with computational fluid dynamics to find optimum configuration of regolith on Mars to receive Ballistic delivery packages

Assistance with design of flight model of RobertDyck's Large Ship.  Model to be flown to confirm or falsify theory of operation of design.

Assistance in filling out positions for My Hacienda project ... 7800 households who collectively support each other on Mars at a level of civilization comparable to First World cultures on Earth.

Assistance with connection to and use of Marspedia service on Mars Society web site.  See Video 54 of 2020 Mars Conference for details.

(th)


Recruiting High Value members for NewMars.com/forums, in association with the Mars Society

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#100 2021-02-14 09:55:42

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,190

Re: Recruiting expertise for NewMars Forum topics:

I am being reminded of how to utilize mars university for creation of course material.
https://en.wikipedia.org/wiki/Mars_Society
https://www.facebook.com/marsu.space/
https://www.marsu.space/

Mars Summer Program 2022
July 5 - August 9

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