I was the MER Spirit Mission Manager, and I was on Mars time for three months in 2004. I adapted to it and liked it. I got to sleep in an extra 40 minutes a day. I had blackout curtains in my bedroom, so that I could sleep in the dark. However I was one of only a few who voted to stay on Mars time after the end of the primary mission. Most of the people on the operations team didn't like Mars time.
This stars whizzing by us are going fast. While the distance may be short, the energy required to rendezvous with a "nearby" star will be far greater than the energy required to travel to a more distant star that has a low relative velocity with ours.
There are plenty of ways to lambaste scientologists (with all of the ways graciously provided directly by them), but this? Yeah sure, the divorce of a Hollywood couple is so unusual, I can see how that would reflect negatively on any group associated with it.
... is rolling his eyes in his grave. The guy who built the very first nuclear reactor on Earth (at least in the last two billion years or so) was an Italian-American physicist.
People in the ISS staring back at Earth while a huge asteroid wipes off the planet killing off all mammals would probably say "yup... that's some nice ROI.. good investing".
And then they realize that they have all men up there on the current rotation...
I'm not saying we expected the rovers to drop dead at the stroke of midnight on sol 91, but even the wildest optimists on the project did not openly dare to hope that we'd even double that 90-sol lifetime.
Actually I was one of the wild optimists on the project, and before landing I predicted that (if they successfully landed and deployed, which was not a given), that they would survive up to solar conjunction in September 2004, or about eight months. More than double the warranty lifetime. I said "Opportunity might make it through conjunction a go a little longer, but I doubt it."
I recall that Jake Matijevic agreed with my calculation -- it was based on his "minimum watt-hours per sol" survival numbers at the time, which he has since improved on by a factor of two or more. But no one on the project predicted survival beyond conunction.
If someone told us five years, we would have laughed. "Impossible", we would have confidently replied...
Absolutely, yes, this rover is a spacecraft. For one thing, it has most of the typical subsystems of a spacecraft, including the computer and data storage, deep space communications gear, solar and battery power systems, attitude sensing, scientific instruments including cameras, etc. It is simply a spacecraft that happens to be sitting on a planetary surface, and that has wheels.
Second, the rover *was* the spacecraft that flew to Mars and landed there. It was not a passenger. The folded up rover inside the aeroshell contained most of the subsystems for the cruise to Mars and entry, descent, and landing. That rover was the heart and brains for the trip to Mars and the landing, and controlled all of those events.
Outside of the rover on the "cruise stage" was the attitude control rockets and propellant, and the star and Sun trackers for attitude sensing, and some more solar panels. Those burned up in the Martian atmosphere when Spirit entered inside its aeroshell. The rover doesn't need those on the surface, since gravity and the ground provide attitude stability, it uses its cameras and an inertial measurement unit for attitude sensing, and uses the wheels for attitude and translational control.
Just make a submersible with flip-out jet engines. If the jet engines are big enough, it will fly. See previous comment about F-4, also referred to as "a triumph of thrust over aerodynamics".
You would have to bring a man back home,... Says who?
I nominate George Bush, with a second flight (to prove it wasn't just a fluke success) carrying Dick Cheney.
I say, point them at each other and let them try to meet up. I've done that calculation. It would take about 300 years, for two rovers with all six wheels working. (Spirit is currently operating with only five working wheels.) We landed them about as far apart as you can on Mars, almost on exactly opposite sides of the planet.
Let's hear it for some other inventors of an enabling technology used on CD's: the Reed-Solomon code! It was invented by mathematicians Irving Reed and Gus Solomon. I happened to know Gus Solomon when he was alive, and he often quipped (in a humorous way), that they never gave him a goddamn dime for using Reed-Solomon codes on CD's. (Nor as I understand did Reed, nor Elwyn Berlekamp, who came up with an efficient decoding algorithm which made R-S codes practical.)
Blown away? Um, no. The Martian atmosphere density is less than 1/100th of Earth's, and so the dynamic pressure of even high winds is not sufficient to so much as nudge a landed probe.
Having read the reports of Mars 3, my theory is that they were off by 20 seconds on when it was supposed to land, and the telemetry actually ended at the moment of impact.
In any case, the Soviets landed many things on Mars before the US did, just not in one piece.
I responded to the problem with a patch in about a day while on vacation in Greece (paying for telephone line use to get a whopping 24 kbps). I just got back from Greece yesterday. I do this for free, yet I plan to get a new version out within about a week for this vulnerability with no extant exploit, of course after adequate testing by our development group which itself will take a day or two. I hope this satisfies our paying customers like yourself.
I would venture to guess that this response time exceeds that of most commercial ventures.
All legal, of course. Some from CDs, some, actually quite a few purchased on iTunes Music Store. All personally bought by team members. I brought in my own speakers--NASA doesn't supply those either. The songs are not broadcast, but simply played in the mission control area.
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I was the MER Spirit Mission Manager, and I was on Mars time for three months in 2004. I adapted to it and liked it. I got to sleep in an extra 40 minutes a day. I had blackout curtains in my bedroom, so that I could sleep in the dark. However I was one of only a few who voted to stay on Mars time after the end of the primary mission. Most of the people on the operations team didn't like Mars time.
This stars whizzing by us are going fast. While the distance may be short, the energy required to rendezvous with a "nearby" star will be far greater than the energy required to travel to a more distant star that has a low relative velocity with ours.
News flash: Combine Harvesters destroy more jobs than they create. Good thing too.
Like everything here ...
You can be trained to hear the lossy compression artifacts. But trust me, you don't want to be. Once you can hear them, you can't unhear them.
RTFA. The mutation was ~85 kya. The popular article also gets this wrong in their title.
There are plenty of ways to lambaste scientologists (with all of the ways graciously provided directly by them), but this? Yeah sure, the divorce of a Hollywood couple is so unusual, I can see how that would reflect negatively on any group associated with it.
Awesome. I still have my Heathkit Vacuum Tube Voltmeter. I need to dig it out and see if it still works ...
Actually MSL is about six times the mass of an MER rover.
... is rolling his eyes in his grave. The guy who built the very first nuclear reactor on Earth (at least in the last two billion years or so) was an Italian-American physicist.
People in the ISS staring back at Earth while a huge asteroid wipes off the planet killing off all mammals would probably say "yup... that's some nice ROI.. good investing".
And then they realize that they have all men up there on the current rotation ...
-- Steven Wright
I'm not saying we expected the rovers to drop dead at the stroke of midnight on sol 91, but even the wildest optimists on the project did not openly dare to hope that we'd even double that 90-sol lifetime.
Actually I was one of the wild optimists on the project, and before landing I predicted that (if they successfully landed and deployed, which was not a given), that they would survive up to solar conjunction in September 2004, or about eight months. More than double the warranty lifetime. I said "Opportunity might make it through conjunction a go a little longer, but I doubt it."
I recall that Jake Matijevic agreed with my calculation -- it was based on his "minimum watt-hours per sol" survival numbers at the time, which he has since improved on by a factor of two or more. But no one on the project predicted survival beyond conunction.
If someone told us five years, we would have laughed. "Impossible", we would have confidently replied ...
The author should have counted. Only seven were listed in the article. He/she left out Asteroid Rover/Sample Return (on page 7 of the announcement).
Second, the rover *was* the spacecraft that flew to Mars and landed there. It was not a passenger. The folded up rover inside the aeroshell contained most of the subsystems for the cruise to Mars and entry, descent, and landing. That rover was the heart and brains for the trip to Mars and the landing, and controlled all of those events.
Outside of the rover on the "cruise stage" was the attitude control rockets and propellant, and the star and Sun trackers for attitude sensing, and some more solar panels. Those burned up in the Martian atmosphere when Spirit entered inside its aeroshell. The rover doesn't need those on the surface, since gravity and the ground provide attitude stability, it uses its cameras and an inertial measurement unit for attitude sensing, and uses the wheels for attitude and translational control.
Just make a submersible with flip-out jet engines. If the jet engines are big enough, it will fly. See previous comment about F-4, also referred to as "a triumph of thrust over aerodynamics".
Let's hear it for some other inventors of an enabling technology used on CD's: the Reed-Solomon code! It was invented by mathematicians Irving Reed and Gus Solomon. I happened to know Gus Solomon when he was alive, and he often quipped (in a humorous way), that they never gave him a goddamn dime for using Reed-Solomon codes on CD's. (Nor as I understand did Reed, nor Elwyn Berlekamp, who came up with an efficient decoding algorithm which made R-S codes practical.)
Blown away? Um, no. The Martian atmosphere density is less than 1/100th of Earth's, and so the dynamic pressure of even high winds is not sufficient to so much as nudge a landed probe.
Having read the reports of Mars 3, my theory is that they were off by 20 seconds on when it was supposed to land, and the telemetry actually ended at the moment of impact.
In any case, the Soviets landed many things on Mars before the US did, just not in one piece.
C+=2 ?
I would venture to guess that this response time exceeds that of most commercial ventures.
Mark Adler
Oops. Forgot to divide by 9.8. It was 500 G's.
Using 193 mph as the impact speed and 30 inches (half the capsule diameter) as the stopping distance, I calculate about 5000 Gs.
Mark Adler
Spirit Mission Manager