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This pre-dust storm panaromic mosaic view was
taken by NASA’s Opportunity rover showing the spectacular view from her
approximate current position in June 2018 after traveling halfway down the
fluid carved slope of Perseverance Valley - while peeing into the interior of vast
Endeavour Crater. This navcam camera photo mosaic was assembled by Ken
Kremer and Marco Di Lorenzo from raw images taken on Sol 5074 (3 May 2018) and colorized. Credit:
NASA/JPL/Cornell/Ken Kremer/kenkremer.com/Marco Di Lorenzo
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CAPE CANAVERAL, FL – An intensifying massive global Martian dust storm blotting out virtually all life-giving sunlight has effectively turned day into night on Mars, thus imperiling the survival of NASA’s long lived Opportunity rover and forcing her to shut down all subsystems and go into sleep mode in a bid to hang on for dear life – at a spot coincidentally called ‘Perseverance Valley.’
“A severe dust storm on Mars threatens Opportunity. We are concerned because there is no signal,” said John Callas, Opportunity project manager at NASA’s Jet Propulsion Laboratory, Pasadena, California, at a hastily arranged NASA briefing for reporters on June 13.
“I declared a spacecraft emergency on June 10 when solar energy production was only 22 watt-hours. Everything was turned off except the master clock.”
By comparison only two weeks ago it was over 645 watt-hours before the dust storm hit. Two days later power dropped to 345 as the storm intensified and then 133 watt-hours after another day.
Will the 14.5 year old Opportunity rover persevere at ‘Perseverance Valley?’
That was the question of the day at a ‘Mars Dust Storm’ media briefing held today, June 13, by NASA and Mars team members representing the rover and the agency’s Red Planet fleet of orbiters and spacecraft monitoring and impacted by the rapidly spreading storm.
“All rover subsystems are off, except a mission clock, programmed to wake the computer to check power levels,” said NASA officials.
“Our expectation at this point is that the rover has gone to sleep, it’s in this low-power mode and it will remain in that low power mode until there’s sufficient energy to charge the batteries back above a certain threshold,” Callas explained at the briefing.
"At that point, the rover will autonomously try to wake up and communicate with us. So at this point, we’re in a waiting mode. We’re listening every day for possible signals from the rover and we'll be prepared to respond to that."
No signals were received during the last attempt on Tuesday, June 12.
The saving grace says the team, may be because its beginning Summertime on Mars and thus the overnight temperatures don’t plunge as much.
Frigid overnight temperatures are the ultimate enemy because they will destroy the delicate electronics and kill the rover.
Callas explained that the rover electronic components are designed to survive temperatures as low as minus 55 degrees C (minus 67 degrees F). Based on calculations from the team its expected that Opportunity wont see temperatures below minus 36 degrees C (minus 33 degrees F).
“The rover also has 8 plutonium RHU’s that generate about 1 watt apiece. So even with no solar energy there is also 8 watts of thermal energy inside the rovers insulated electronics box.”
In a strange twist, the dust storm particles have actually warmed the Red
Planet.
“The good news there is the dust storm has warmed temperatures on
Mars. We’re also going into the summer season, and so the rover will not get as
cold as it would normally.”
“We’ve done an estimate that
shows the rover should stay above its minimum allowable operating temperatures
for the long term, so we should be able to ride out the storm. When the skies
clear and the rover begins to power up, it should begin to communicate with
us.”
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This series of images
shows simulated views of a darkening Martian sky blotting out the Sun from
NASA’s Opportunity rover’s point of view, with the right side simulating
Opportunity’s current view in the global dust storm (June 2018). The
left starts with a blindingly bright mid-afternoon sky, with the sun appearing
bigger because of brightness. The right shows the Sun so obscured by dust it
looks like a pinprick. Each frame corresponds to a tau value, or measure of
opacity: 1, 3, 5, 7, 9, 11. Credits: NASA/JPL-Caltech/TAMU
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But no one really knows because there has been no communication from Opportunity since June 10 because the golf cart sized robot has gone to sleep to conserve power until sufficient daylight returns to charge herself up.
In a nutshell, only time will tell if Opportunity is revived and phones home.
In fact it has gotten so dark over Opportunity that atmospheric opacity has rocketed - as measured by tau that reached a record high of 10.8 on June 10, causing energy production to plummet, said Callas.
“It’s completely black on Mars!”
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This graphic shows how
the energy available to NASA’s Opportunity rover on Mars (in watt-hours)
depends on how clear or opaque the atmosphere is (measured in a value called
tau). When the tau value (blue) is high, the rover’s power levels (yellow)
drop. Credits: NASA/JPL-Caltech/New Mexico Museum of
Natural History
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Furthermore, the storm is still growing in intensity with ever more
dust being levitated and thrown up to higher levels in the atmosphere – meaning
it will take more time for the dust to settle and daylight to return and the solar
panels to collect solar rays.
“The current
storm is just 2 or 3 days away from becoming a planet encircling event,” said Rich Zurek, chief scientist for the Mars Program Office at
NASA's Jet Propulsion Laboratory in Pasadena, California, at the briefing.
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This set of images from
NASA’s Mars Reconnaissance Orbiter shows a fierce dust storm is kicking up on
Mars in June 2018, with NASA’s Opportunity and Curiosity rovers on the surface
indicated as icons. Credits:
NASA/JPL-Caltech/MSSS
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I asked Zurek and Calles to comment about how long the storm will continue to intensify ?
And how long can the rover survive in the very low power mode - weeks/months?
“In some sense the storm won’t get too much worse. What is changing is the storm is producing a dust haze that is spreading over the planet and getting raised higher into the atmosphere. That can lengthen depending on how long it takes for the storm to clear,” Zurek told me.
“We aren’t expecting the opacity over Opportunity to get alot worse - but it doesn’t matter because there is almost no sunlight reaching the ground anyway. It’s a very dusty sky right now.”
“How long the storm will last? Well we are not certain of that. That is one of the issues that we are trying to understand.”
“We want to learn what initiates that so-called decay phase where the dust areas stop being raised into the atmosphere and everything begins to fall out. The winds are part of that and will eventually die down. And when that happens – next week or two weeks from now – we don’t know,” Zurek explained to Space UpClose.
“As long as the rover stays warm enough, and our predictions are that it will, then we can go any number of days,” Callas told me.
“We are approaching summer and have not even hit the warmest part of the year yet for the rover at this site.”
“In terms of the low power mode, well the rover actually goes into that every day. We have a process we call deep sleep in which once we are done with our activities for the day, we disconnect the batteries from the rover and only the mission clock is connected. And so we have been deep sleeping now for thousands of Sols.”
“And so this is like deep sleeping- except we are doing it throughout the entire day, not just at night,” Callas replied to Space UpClose.
Science operations for NASA's Opportunity rover "have been temporarily suspended as it waits out a growing dust storm on Mars,” NASA said in an earlier statement.
“A dark, perpetual night has settled over the rover's location in Mars' Perseverance Valley,” NASA reported on June 10.
The 2018 storm is now far worse than the prior global dust storm that afflicted Opportunity back in 2007 and is centered over the rover – and covers about a quarter of the planet!
“The storm is one of the most intense ever observed on the Red Planet.”
The long lived robot was launched in 2003, landed in 2004 and has been making breakthrough science and exploration discoveries ever since during its utterly remarkable 14.5-year-long overland trek across the 4th planet from the sun.
“As of June 10, it covered more than 15.8 million square miles (41 million square kilometers) – about the area of North America and Russia combined. It has blocked out so much sunlight, it has effectively turned day into night for Opportunity, which is located near the center of the storm, inside Mars' Perseverance Valley.”
See herein our exclusive Opportunity rover mosaics showing the view from Perseverance Valley and our route map – created by the imaging team of Ken Kremer and Marco Di Lorenzo.
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Historic 1st descent down Martian
gully. Panoramic view looking down Perseverance Valley after entry at top was
acquired by NASA’s Opportunity rover scanning from north to south. It shows
numerous wheel tracks at left, center and right as rover conducted walkabout
tour prior to starting historic first decent down a Martian gully – possibly
carved by water – and looks into the interior of Endeavour crater. Perseverance
Valley terminates down near the crater floor in the center of the panorama. The
far rim of Endeavour crater is seen in the distance, beyond the dark floor.
Rover mast shadow at center and deck at left. This
navcam camera photo mosaic was assembled by Ken Kremer and Marco Di Lorenzo
from raw images taken on Sol 4780 (5 July 2017) and colorized. Credit:
NASA/JPL/Cornell/Ken Kremer/kenkremer.com/Marco Di Lorenzo
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As a
result of the ever thicker swirling dust, Opportunity's power levels had dropped significantly thus requiring
the rover to shift to minimal operations with only limited communications every
few days to conserve power - initially. Contact was lost on June 10.
Power is also needed to run the heaters that keep the vital electronic boxes warm and protect them from deadly sub-freezing temperatures.
Opportunity’s twin sister rover Spirit died in 2011 when the robots solar panels produced insufficient power to the electronics box heaters because it was stuck in a sand trap with the solar panels facing away from the sun during a bone chilling Martian winter.
“Engineers will monitor the rover's power levels closely in the week to come. The rover needs to balance low levels of charge in its battery with sub-freezing temperatures. Its heaters are vitally important to keeping it alive, but also draw more power from the battery.”
The giant dust storm began May 30 and has been growing even
since in intensity and area.
By June 6 it had ballooned to more than 7 million square miles (18
million square kilometers).
The dust storm was first detected by the Mars Reconnaissance Orbiter (MRO) - another NASA spacecraft currently orbiting the
Red Planet and which relays a portion of
the science data back to scientists on Earth.
An impressive global map of Mars showing the growing dust storm (as a GIF) was taken over a series of days in early June 2018 by
the Mars Color Imager (MARCI) camera onboard the MRO spacecraft. See herein.
The approximate locations of NASA’s Opportunity rover at Endeavour Crater and Curiosity at Gale Crater (on the other side of the planet) are marked with icons.
The approximate locations of NASA’s Opportunity rover at Endeavour Crater and Curiosity at Gale Crater (on the other side of the planet) are marked with icons.
Curiosity is unaffected by the dust storm because it is nuclear
powered and not dependent on the sun in any way with solar panels. It has taken images that show
the daytime skies darkening and haziness growing significantly.
Opportunity is currently descending down and exploring Perseverance Valley located along the eroded western rim of the gigantic 22-km (14-mi) diameter impact crater named Endeavour.
Although Opportunity was only warrantied for “90 Sols” of operation, it is now enjoying its 15th year of continuous operations on the frigid alien world.
“Perseverance Valley” is an ancient fluid-carved valley “possibly water-cut” that could hold groundbreaking clues to the potential origin and evolution of life on Mars – if it ever existed.
Opportunity is currently descending down and exploring Perseverance Valley located along the eroded western rim of the gigantic 22-km (14-mi) diameter impact crater named Endeavour.
Although Opportunity was only warrantied for “90 Sols” of operation, it is now enjoying its 15th year of continuous operations on the frigid alien world.
“Perseverance Valley” is an ancient fluid-carved valley “possibly water-cut” that could hold groundbreaking clues to the potential origin and evolution of life on Mars – if it ever existed.
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Opportunity rover looks south
from the top of Perseverance Valley along the rim of Endeavour Crater on Mars
in this partial self portrait including the rover deck and solar panels.
Perseverance Valley descends from the right and terminates down near the crater
floor. This navcam camera photo mosaic was assembled from raw images taken on
Sol 4736 (20 May 2017) and colorized. Credit: NASA/JPL/Cornell/Marco Di
Lorenzo/Ken Kremer/kenkremer.com
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As of today, June 13,
2018, long lived Opportunity has survived over 5114 Sols (or Martian days)
roving the harsh environment of the Red Planet.
Opportunity has taken over
228,771 images and traversed over 28.06 miles (45.16 kilometers) - more than a marathon.
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NASA’s Opportunity rover acquired
this Martian panoramic view from a promontory that overlooks Perseverance
Valley below – scanning from north to south. It is centered on due East and
into the interior of Endeavour crater. Perseverance Valley descends from the
right and terminates down near the crater floor in the center of the panorama.
The far rim of Endeavour crater is seen in the distance, beyond the dark floor.
Rover deck and wheel tracks at right. This navcam camera photo mosaic was
assembled from raw images taken on Sol 4730 (14 May 2017) and colorized.
Credit: NASA/JPL/Cornell/Ken Kremer/kenkremer.com/Marco Di Lorenzo
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Stay tuned here for Ken's continuing Earth and Planetary science and human spaceflight news: www.kenkremer.com –www.spaceupclose.com – twitter @ken_kremer – email: ken at kenkremer.com
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14 Year Traverse Map for NASA’s Opportunity rover from 2004 to
2018. This map shows the entire 45 kilometer (28 mi) path the rover has driven
on the Red Planet during over 14.5 Earth years (7.5 Mars years) and more than a
marathon runners distance for over 5115 Sols, or Martian days, since landing
inside Eagle Crater on Jan 24, 2004 – to current location at Perseverance
Valley at the western rim of Endeavour Crater. The rover reached Perseverance
Valley in May 2017 and descended about halfway by June 2018. Its likely a water carved Martian gully.
Opportunity surpassed Marathon distance on Sol 3968 after reaching 11th Martian
anniversary on Sol 3911. Opportunity discovered clay minerals at Esperance –
indicative of a habitable zone – and searched for more at Marathon Valley.
Credit: NASA/JPL/Cornell/ASU/Marco Di Lorenzo/Ken Kremer/kenkremer.com
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