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I made my comments after hearing Jim Bell describe in detail what has to happen for success; I don't think NASA wants to gamble $$11 Billion on a less than 50% overall chance of success. I personally wouldn't take that chance with the diminishing budget of the space agency; given the odds stated for success, the economics argue against the funding. There are too many high risk operations that need to succeed 100% in order for a sample return.
I believe that in the future, all talks which are recorded will be available through the Yellowstone Valley Astronomy Association Facebook page.
I'm convinced that Elon Musk will play some role in Mars sample return; his approach will be significantly less complex than that proposed by NASA and ESA. No one should underestimate his resolve towards the Red Planet!
A rebirth of the Red Dragon program could occur with not too much fuss and bother if NASA threw some money towards it. There's already a Mars capable vehicle available in Falcon Heavy and Vulcan-Centaur is waiting in the wings...
Overall, the risk is similar to being an airline pilot who flies routinely around 36,000 feet approximately 300 days per year. The daily exposure would be far less on Callisto, as a regolith covered habitat needed for thermal protection, in addition to radiation, would be where most activity would take place. Figure maybe only 4-6 hours per day outside the habitat would reduce the radiation exposure by 75%.
GW-
Upon checking, I found a reference stating that the surface radiation on Callisto is 0.01 rem per day without any protective measures.
GW-
That is for the most part correct; there is one period during the orbit around Jupiter where there's a radiation "plume" which greatly increases the effects with concurrent radiation. I may be in error writing this in it's details, as I've loaned my copy of Entering Space to a friend and can't check this. I will check these details and update as needed.
In Minnesota they wear flip flops and shorts out in the snow!
I would like to express my deep appreciation that both GW Johnson and tahanson43206 virtually attended Dr. Bell's excellent presentation. The attendance was below normal--probably due to a PBR (Professional Bull Riders) event at the local arena and a gun show in town. Our core group of regulars was there, tho'. The weather was also the first shirt-sleeve warm day this Spring.
I will point out to our members that Robert Zubrin's book, "Entering Space" details out the radiation environment on Callisto and other Jovian moons. I would be interested in the views of others here about his assessment. The background cosmic rays are not an immediate threat to life and becomes problematic after a half human lifetime of exposure. IMHO, Callisto would be an admirable site for a large astronomical observatory and radio observatory. The human population there could maintain the systems more readily than we can "fix" Hubble and the JWST.
I will make an effort to have the "lady asking questions" become a newmars forum member, as she's the President of the YVAA, and is a PA specializing in family medicine. She could help a lot with some of the health subjects in Mars colonization.
GW & Tom--
Thanks for attending virtually!
I now routinely use headphones in order to hear anything at these online presentations. That takes care of the sound system issues.
Hey Thomas, GW, and others:
I will be introducing Jim Bell and moderating any questions from the audience.
Here is what I have from our IT guy for today's meeting with Dr. Jim Bell:
Topic: YVAA Zoom Talk -
Time: Apr 13, 2024 03:00 PM Mountain Time (US and Canada)
Join Zoom Meeting
https://us02web.zoom.us/j/85017538813?p … lvaDRSUT09
Meeting ID: 850 1753 8813
Passcode: 139105
---
One tap mobile
+17193594580,,85017538813#,,,,*139105# US
+12532050468,,85017538813#,,,,*139105# US
I too watched the Angry Astronaut interview with the PR guy from Lockheed Martin. The Nuclear Thermal vehicle is intended to go from LEO to a LMO and not itself be a lander. Instead, it's to provide a Mars Base in orbit and a return point from several short duration visits to the planetary surface.
To all interested parties: I'm currently in the process of developing a talk for the Yellowstone Valley Astronomy Association in Billings,Montana. The first key to figuring out how life "came to be" here on Earth is in the abiotic synthesis of biological molecules necessary for life. My talk will be based on the work of Harold C. Urey and Stanley Miller and the so-called Miller-Urey experiment of 1952 at the University of Chicago. In this experiment a glass vessel was charged with a "proteoatmosphere" of Methane, Ammonia, Hydrogen, and water vapor.A set of electrodes was used to simulate lighting, and after about a week of electrical discharges, a brown liquid resulted. After analysis by a very crude paper chromatography (by present standards), Ninhydrin spray (specific for amino acids) detected many spots corresponding to several known amino acids, notable glycine, alanine, a dipeptiede (glycylglycine), and several other organic compounds in various traces. I heard a talk by Dr. Urey whilst a graduate student at the University of Wyoming in 1970. This experiment founded a field known as COSMOCHEMISTRY. It was more than a good start, since subsequently Stanley Miller's original samples were found at UCSD by a graduate student and reanalyzed using HPLC (High Performance Liquid Chromatography) with amazing findings of 17 of the 20 naturally occurring amino acids found in almost all living organisms! Only the 3 sulfur bearing amino acids were absent, probably due to the absence of any Hydrogen Sulfide in the starting mixture.
Some recent studies at the Scripps Institute of Oceanography while investigating oceanic thermal vents have also found strong evidence of Methionine and Cystiene in isolated samples.
There is a lot of good science being done across the world, but not nearly enough to satisfy me--and probably the late professor Urey!
Background: Harold Clayton Urey received the 1933 Nobel Prize in Chemistry for his discovery of Deuterium, was responsible for the purification and mass production of enough U-235 to destroy Nagasaki. After the war, he was a principal founder of the US Atomic Energy Commission.
Added as an edit I had the great honor to meet Dr. Urey and shake his hand at University of Wyoming.
I'm hoping that this is a successful flight--primarily for the crew onboard. This may be the ONLY flight of this troubled vehicle....
I'd be OK with un-sticky-ing all of them, other than those needed for stating rules for posters.
Regarding "sticky topics," I suggest we do a little housekeeping and reduce the numbers about 90%. Jes sayin'.
I recall reading that both Callisto and Ganymede have very tenuous atmospheres of Carbon Dioxide, the density correlated to the very low gravitational constants. I can't recall the source of this information--possibly in Robert Zubrin's book "Entering Space."
I envision Callisto as strictly a research station and possibly a safe haven from longer deep space missions to the Saturn system. Allow a crew to have some new social activities and not be worried about the systems on the space vessel
I'm initiating this thread in response to a suggestion by moderator tahanson43206. A repository point for all suggestions regarding missions, research proposals, and wild comments involving Callisto.
I'm gonna set up a new Callisto thread for updates on the most distant from the host planet of the 4 Galilean satellites. It's the only practical place from a radiation survivability standpoint.
Our meeting is 13 April at 3:00 PM MDT. We meet at the Community Room in Billings Public Library. I need to contact our Sec-Treas., as he's the IT expert.
I'm gonna contact our IT specialist about being able to have other guests attend via Zoom to the Jim Bell talk. I met Jim about 20 years ago in Casper, Wyoming when he was there as a NASA roving ambassador and gave the Central Wyoming Astronomical Society a great presentation about Mars and showed a short video he put together from the Opportunity rover with a visual circumnavigation tour of Victoria Crater on Mars.
The term "Cosmochemistry" was first used by Dr. Harold C. Urey, and was used to describe the work he was pursuing late in his distinguished career (Nobel Prize in 1933 for his discovery of Deuterium), and after his work with Oak Ridge National Laboratory to isolate U-235 for the bomb. His coworker was Stanley Miller, and together they published the work on the origin of building block molecules of life from conditions on primordial Earth. They isolated several amino acids and other essential molecules upon which life is based from the Miller-Urey apparatus at University of Chicago and later at UCSD. This was a spark-discharge system they built to mimic lightning in an atmosphere of methane, ammonia, hydrogen and saturated with water vapor.
Dr. Urey was a guest lecturer and seminar presenter at the University of Wyoming whilst I was still a graduate student in Physical Chemistry. I had the privilege of meeting him before he gave his presentation entitled "Cosmochemistry." My talk will be primarily to honor his legacy and talk about ongoing developments based on his work.
As a side note, his original experimental samples were found just a few years ago at UCSD, and subsequently re-analyzed using HPLC instead of crude paper chromatography. I believe that something like 17 of the essential amino acids were isolated and identified some 60 years after the original samples were created. So...pulling together a talk from the available information and putting into understandable terms for the general public seems daunting.
In the meantime, I've been elected as vice president of the Yellowstone Valley Astronomy Association in Billings, MT, which means I am in charge of arranging speakers for our wintertime monthly meetings. We do public star parties during the summer months.
I've arranged for Dr. Jim Bell of ASU to give us a Zoom presentation about the rovers on Mars this coming month of April. I'm doing a presentation for the club on Cosmochemistry in May, so I'm still active and not out of it yet!