IPB

Welcome Guest ( Log In | Register )

6 Pages V   1 2 3 > »   
Closed TopicStart new topic
Gut feeling...
SFJCody
post May 22 2008, 08:15 PM
Post #1


Member
***

Group: Members
Posts: 771
Joined: 8-February 04
From: Arabia Terra
Member No.: 12



Something I have not posted online before...
Back in 2003, as four spacecraft approached Mars, I wrote down on a piece of paper my guess (based on nothing more than public information & gut feeling) at what each craft's chance of success (either at landing or orbital insertion) might be.
My guesses were:

Nozomi: 15%
Beagle 2: 20%
MER A: 60%
MER B: 60%
Mars Express: 85%

In 2005 I guessed that MRO had a 90% chance of success

Now, in 2008, I'm going to put a figure on Phoenix. That figure is:

55%


What do you think? Too low? Too high?
Go to the top of the page
 
+Quote Post
john_s
post May 22 2008, 08:23 PM
Post #2


Member
***

Group: Members
Posts: 527
Joined: 3-December 04
From: Boulder, Colorado, USA
Member No.: 117



Too low according to my gut, which reports in at about 82%...
Go to the top of the page
 
+Quote Post
SFJCody
post May 22 2008, 08:26 PM
Post #3


Member
***

Group: Members
Posts: 771
Joined: 8-February 04
From: Arabia Terra
Member No.: 12



QUOTE (john_s @ May 22 2008, 09:23 PM) *
Too low according to my gut, which reports in at about 82%...



Good to know that planetary pros are more optimistic! smile.gif
Go to the top of the page
 
+Quote Post
djellison
post May 22 2008, 08:54 PM
Post #4


Administrator
****

Group: Chairman
Posts: 13600
Joined: 8-February 04
Member No.: 1



I've been trying to figure this out for myself. I decided that Phoenix has a better chance than Lewis Hamilton has of not winning the Monaco Grand Prix.

67% is the figure I've come up with. 2/3rds - which, by chance, is the ratio of powered decent landings on Mars.

Doug
Go to the top of the page
 
+Quote Post
ElkGroveDan
post May 22 2008, 09:03 PM
Post #5


Senior Member
****

Group: Admin
Posts: 4636
Joined: 15-March 05
From: Sloughhouse, CA
Member No.: 197



I'll say 83% which is the ratio of successful U.S. Mars landing attempts (5 of 6).


--------------------
If Occam had heard my theory, things would be very different now.
Go to the top of the page
 
+Quote Post
tedstryk
post May 22 2008, 09:04 PM
Post #6


Interplanetary Dumpster Diver
****

Group: Moderator
Posts: 4159
Joined: 17-February 04
From: Powell, TN
Member No.: 33



With all the MPL discussion and the fact that we haven't found it, I am left wondering about something. MARDI on Phoenix was turned off because of fear that it would interfere with the EDL sequence and cause the mission to crash. I wonder if that is what did MPL in? If the generally accepted failure mode is wrong, this would be a favorite of mine (in terms of preference, not necessarily likelihood), because Phoenix has already worked around it.


--------------------
Go to the top of the page
 
+Quote Post
ugordan
post May 22 2008, 09:08 PM
Post #7


Senior Member
****

Group: Members
Posts: 3559
Joined: 1-October 05
From: Croatia
Member No.: 523



My greatest paranoia, when it comes to Mars landers, is landing on rocks, tipping over craters or other rough terrain features. It's the one thing you can't (just yet) control and it in the end depends upon luck. I can't really quantify my gut feeling of Phoenix' chance of successful landing, but I'm sure glad they picked a really flat target area.

Ted, my wondering about MPL led me to think it could have in fact been the terrain that got to MPL in the end. As opposed to Phoenix site, some of that terrain is dreadful (although low illumination angle brings this effect up).


--------------------
Go to the top of the page
 
+Quote Post
ustrax
post May 22 2008, 09:22 PM
Post #8


Special Cookie
****

Group: Members
Posts: 2168
Joined: 6-April 05
From: Sintra | Portugal
Member No.: 228



My gut feeling...having into account the previous uncharted abysses to be (not encouragin isn't it?)...:

100%!

Let us have faith...in what faith can help us... tongue.gif

I am really trustful about Phoenix...trustful about a mission marking a new ground...


--------------------
"Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe
Go to the top of the page
 
+Quote Post
centsworth_II
post May 22 2008, 09:23 PM
Post #9


Senior Member
****

Group: Members
Posts: 2024
Joined: 28-December 04
Member No.: 132



QUOTE (ElkGroveDan @ May 22 2008, 05:03 PM) *
I'll say 83% which is the ratio of successful U.S. Mars landing attempts (5 of 6).

I'd say 90%... I think they're getting better.
Go to the top of the page
 
+Quote Post
kwan3217
post May 22 2008, 09:30 PM
Post #10


Junior Member
**

Group: Members
Posts: 86
Joined: 27-August 05
From: Geosynchronous earth orbit
Member No.: 477



Around 90%. I have seen many movies and animations of this thing working, and none of it not, so I'm conditioned to think it will work.
Go to the top of the page
 
+Quote Post
SFJCody
post May 22 2008, 09:42 PM
Post #11


Member
***

Group: Members
Posts: 771
Joined: 8-February 04
From: Arabia Terra
Member No.: 12



QUOTE (ElkGroveDan @ May 22 2008, 10:03 PM) *
I'll say 83% which is the ratio of successful U.S. Mars landing attempts (5 of 6).


Unless you count the two DS2 probes as landers, which would make it 5/8
Go to the top of the page
 
+Quote Post
mcaplinger
post May 22 2008, 09:43 PM
Post #12


Senior Member
****

Group: Members
Posts: 1230
Joined: 13-September 05
Member No.: 497



QUOTE (tedstryk @ May 22 2008, 01:04 PM) *
With all the MPL discussion and the fact that we haven't found it, I am left wondering about something. MARDI on Phoenix was turned off because of fear that it would interfere with the EDL sequence and cause the mission to crash. I wonder if that is what did MPL in?

The probability that the software bug with the leg deployment on MPL caused its failure is something greater than 50%. The probability that the MARDI/PACI issue caused it is a very small number (1:100000 would be my off-the-cuff guess). So I'm going with the software bug (which has also already been addressed for PHX.)


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post
SpaceListener
post May 22 2008, 10:53 PM
Post #13


Member
***

Group: Members
Posts: 242
Joined: 19-August 07
Member No.: 3299



I have high trust about the Phoenix's EDL plan which is much better prepared than any previous Mars landing spacecraft.

However, there is one thing that cannot control the safe landing is the condition of the terrain which Phoenix will land on Green Valley in spite of the fact that the terrain is believed to be very smooth in "General Terms". After combining the three factors, I am puting that the success factor in landing safely on Mars is about 80%.
Go to the top of the page
 
+Quote Post
nprev
post May 23 2008, 02:20 AM
Post #14


Senior Member
****

Group: Moderator
Posts: 6828
Joined: 8-December 05
From: Los Angeles
Member No.: 602



Gotta go with 90% or greater. They've learned a LOAD of lessons, have the best weather recon in place ever, and hardware keeps getting more & more reliable. It's all evolutionary.


--------------------
A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
Go to the top of the page
 
+Quote Post
centsworth_II
post May 23 2008, 02:23 AM
Post #15


Senior Member
****

Group: Members
Posts: 2024
Joined: 28-December 04
Member No.: 132



QUOTE (nprev @ May 22 2008, 09:20 PM) *
Gotta go with 90% or greater. They've learned a LOAD of lessons...

Right. I don't see why you would use the overall average for success, which includes the steepest part of the learning curve.
Go to the top of the page
 
+Quote Post

6 Pages V   1 2 3 > » 
Closed TopicStart new topic

 



RSS Lo-Fi Version Time is now: 20th April 2014 - 03:12 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.