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Mars Opportunity Rover Is In Danger of Dying From a Dust Storm (engadget.com)
According to NASA, the Mars Opportunity rover is currently trying to survive an intensifying dust storm on the red planet. "The storm's atmospheric opacity -- the veil of dust blowing around, which can blot out sunlight -- is now much worse than a 2007 storm that Opportunity weathered," reports NASA. "The previous storm had an opacity level, or tau, somewhere above 5.5; this new storm had an estimated tau of 10.8 as of Sunday morning." Engadget reports: The storm was first detected on Friday June 1st by the Mars Reconnaissance Orbiter, at which point the rover's team was notified because of the weather event's proximity to Opportunity. The rover uses solar panels, so a dust storm could have an extremely negative impact on Opportunity's power levels and its batteries. By Wednesday June 6th, Opportunity was in minimal operations mode because of sharply decreasing power levels. The brave little rover is continuing to weather the storm; it sent a transmission back to Earth Sunday morning, which is a good sign. It means there's still enough charge left in the batteries to communicate with home, despite the fact that the storm is continuing to worsen.
"The brave little rover": https://xkcd.com/695/
The more pressing problem isn't that it can't reboot, it's that it won't be able to clean its panels after the storm, and that's assuming it can even do that. Not to mention the drop in efficiency from getting the panels scarred up by abrasive dust.
Godspeed little rover, keep up the fight!
It needs battery to keep the internal components at safe temperature levels. It is not about calling home; it is about not freezing.
Since this article doesn't explain it, an optical depth tau value of 10.8 means approximately 0.002% of the sunlight is reaching the rover, compared to 0.4% for the last storm. It's really, really dark out there.
...someone needs to loose their engineering degree.
Someone needs to remember this hardware was originally expected to last 90 days. It's been running for over fourteen fucking years.
This would probably be one of those times where you should STFU about failures in engineering and design, as the statistics tend to speak for themselves.
Opportunity and Spirit are not fitted with any mechanism to clear their solar panels. Originally, it was assumed that dust on the panels would be what would end the mission. But winds and whirlwinds were found on the planet, these occasionally blew dust from the panels, and the mission was extended.
The pressing problem is that there won't be enough energy to keep the heaters running, the electronics will cool down to -50C, and either the heaters won't turn back on when the sun returns, or, if they do, the electronics won't work when they defrost.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
0.4% of the sunlight wouldn't have be enough to make the solar panels work. So a greater darkness than that doesn't really make any difference. It might as well be pitch black if the intensity is below 1%.
What is important, then, is how long this dust storm will last.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
That's 14 earth years, not 14 fucking years.
That being said, I didn't know that fucking was a planet, we should let more people know, it would really help build interest in space exploration.
On one hand, I think those engineers need a discussion about underestimating capabilities.
On the other, I think they need to be given god damm medals for making a project beat its lifespan estimates, not by 10%, not by 100%, not by 1000%, but by 5500%.
The decay of Pu-238 will not be what limits the Curiosity mission. It has a half-life of 87.7 years. The RTG that uses that decay to produce electricity (and, perhaps more importantly at the moment, heat to keep the electronics happy) decays more quickly than that. But the Voyager probes still have enough electricity to communicate with earth forty years after launch.
The limiting factor for Curiosity will probably be its moving parts. Specifically, its drive motors and wheels. The wheels have taken quite a beating, and may eventually be so damaged that they can no longer provide adequate traction. The JPL guys are really clever, and can probably drive Curiosity even with the complete loss of one wheel.
But even if Curiosity stopped moving tomorrow, it would almost certainly still be useful for stationary science. It can continue to gather weather data (including measuring atmospheric methane, which hit the news recently), take pictures, shoot lasers, and sample rocks, probably for years. One of the Viking landers lasted 6 years on the surface, and that mission ended only after a bad software update.
You know how I can tell that neither of you actually read the article?
The main concern here isn't the dust storm itself. It's the need to keep the rover's heaters operational while maintaining a minimal power level in the batteries.
No sig today...
Seriously, you have to take those claims of "designed for 90 days of operation" with some big grains of salt.... There's no way they'd spend all the money, time and energy on R&D to get something like this put on Mars, when they REALLY only expected it would be used for a few months.
That might be the length of time they NEEDED to complete the original planned research project, so in a worst-case scenario, NASA doesn't have to say they failed. But I'm quite certain this thing was engineered with the hopes it would run for years and years -- as it has done.
someone needs to loose their engineering degree.
I don't know about that but somebody definitely needs to learn to spell "lose".
It's only four letters, FFS.
No sig today...
At the moment the problem is not how much dust will be on the solar panels after the storm. It is that it will lose all power during the storm, the heaters will stop working, and will then be unable to reactivate afterward.
The story reports an optical depth of the dust storm of tau=10.8. This is astoundingly dark. The transmittance of light through the atmosphere is 1/e^tau so that only 1/50,000 (0.002%) of the sunlight is getting through! It is effectively perpetual night there right now. This is probably darker than even the heaviest storm clouds on Earth (which only go up to blocking 1/20,000 of the sun light). Thus far the storm has cut off power for six days.
Although the storm also moderates temperature, since it prevents radiation cooling at night, it also means that the day time high temperatures are not reached either, so that the heaters have to be cranked up constantly (though not to the level of coldest night chill), with no power replacing what is being drained from the batteries.
It the batteries drain to the level that they can no longer supply the heaters then whether there is dust on the panels after the storm ends will be moot. Opportunity will be dead.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj