Category: Research

NASA: Six Facts About Recovering The Mars Opportunity Rover

NASA’s Opportunity rover has been silent since June 10, when a planet-encircling dust storm cut off solar power for the nearly-15-year-old rover. Now that scientists think the global dust storm is “decaying” — meaning more dust is falling out of the atmosphere than is being raised back into it — skies might soon clear enough for the solar-powered rover to recharge and attempt to “phone home.”

No one will know how the rover is doing until it speaks. But the team notes there’s reason to be optimistic: They’ve performed several studies on the state of its batteries before the storm, and temperatures at its location. Because the batteries were in relatively good health before the storm, there’s not likely to be too much degradation. And because dust storms tend to warm the environment — and the 2018 storm happened as Opportunity’s location on Mars entered summer — the rover should have stayed warm enough to survive.

What will engineers at NASA’s Jet Propulsion Laboratory in Pasadena, California, be looking for — and what will those signs mean for recovery efforts?

A tau below 2

Dust storms on Mars block sunlight from reaching the surface, raising the level of a measurement called “tau.” The higher the tau, the less sunlight is available; the last tau measured by Opportunity was 10.8 on June 10. To compare, an average tau for its location on Mars is usually 0.5.

JPL engineers predict that Opportunity will need a tau of less than 2.0 before the solar-powered rover will be able to recharge its batteries. A wide-angle camera on NASA’s Mars Reconnaissance Orbiter will watch for surface features to become visible as the skies clear. That will help scientists estimate the tau.

Updates on the dust storm and tau can be found here.

Two Ways to Listen for Opportunity

Several times a week, engineers use NASA’s Deep Space Network, which communicates between planetary probes and Earth, to attempt to talk with Opportunity. The massive DSN antennas ping the rover during scheduled “wake-up” times, and then search for signals sent from Opportunity in response.

In addition, JPL’s radio science group uses special equipment on DSN antennas that can detect a wider range of frequencies. Each day, they record any radio signal from Mars over most of the rover’s daylight hours, then search the recordings for Opportunity’s “voice.”

Rover faults out

When Opportunity experiences a problem, it can go into so-called “fault modes” where it automatically takes action to maintain its health. Engineers are preparing for three key fault modes if they do hear back from Opportunity.

  • Low-power fault: engineers assume the rover went into low-power fault shortly after it stopped communicating on June 10. This mode causes the rover to hibernate, assuming that it will wake up at a time when there’s more sunlight to let it recharge.
  • Clock fault: critical to operating while in hibernation is the rover’s onboard clock. If the rover doesn’t know what time it is, it doesn’t know when it should be attempting to communicate. The rover can use environmental clues, like an increase in sunlight, to make assumptions about the time.
  • Uploss fault: when the rover hasn’t heard from Earth in a long time, it can go into “uploss” fault — a warning that its communication equipment may not be functioning. When it experiences this, it begins to check the equipment and tries different ways to communicate with Earth.

What happens if they hear back?

After the first time engineers hear from Opportunity, there could be a lag of several weeks before a second time. It’s like a patient coming out of a coma: It takes time to fully recover. It may take several communication sessions before engineers have enough information to take action.

The first thing to do is learn more about the state of the rover. Opportunity’s team will ask for a history of the rover’s battery and solar cells and take its temperature. If the clock lost track of time, it will be reset. The rover would take pictures of itself to see whether dust might be caked on sensitive parts, and test actuators to see if dust slipped inside, affecting its joints.

Once they’ve gathered all this data, the team would take a poll about whether they’re ready to attempt a full recovery.

Not out of the woods

Even if engineers hear back from Opportunity, there’s a real possibility the rover won’t be the same.

The rover’s batteries could have discharged so much power — and stayed inactive so long — that their capacity is reduced. If those batteries can’t hold as much charge, it could affect the rover’s continued operations. It could also mean that energy-draining behavior, like running its heaters during winter, could cause the batteries to brown out.

Dust isn’t usually as much of a problem. Previous storms plastered dust on the camera lenses, but most of that was shed off over time. Any remaining dust can be calibrated out.

Send Opportunity a postcard

Do you miss Opportunity as much as the rover’s team? You can write a message sharing your thoughts here.

Read more about Opportunity at:

https://mars.nasa.gov/mer/highlights/

 

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Brighter Future For Us All: High-Fidelity Images of Sun’s Atmosphere Tell The Tale

A Southwest Research Institute-led team discovered never-before-detected, fine-grained structures in the Sun’s outer atmosphere, or corona. The team imaged this critical region in detail using sophisticated software techniques and longer exposures from the COR-2 camera onboard NASA’s Solar and Terrestrial Relations Observatory-A (STEREO-A).

The Sun’s outer corona is the source of the solar wind, the stream of charged particles that flow outward from the Sun in all directions. Measured near Earth, the magnetic fields embedded within the solar wind are intertwined and complex.

“Previous images showed the outer corona as a smooth structure, but in deep space, the solar wind is turbulent and gusty,” said SwRI’s Dr. Craig DeForest, a solar physicist and lead author of “The Highly Structured Outer Corona,” an article published by Astrophysical Journal July 18, 2018.

“Using new techniques to improve image fidelity, we realized that the corona is not smooth, but structured and dynamic. Every structure that we thought we understood turns out to be made of smaller ones and to be more dynamic than we thought.”

To understand the corona, DeForest and his colleagues started with extended exposures of STEREO-A’s coronagraph images – pictures of the Sun’s atmosphere produced by a special telescope that blocks out light from the bright solar disk.

The coronagraph is sensitive enough to image the corona in great detail, but in practice its measurements are polluted by noise both from the space environment and the instrument itself. The team’s key innovation was identifying and separating out that noise, boosting the signal-to-noise ratio and revealing the outer corona in unprecedented detail.

“We couldn’t tinker with the instrument itself, so we took a software approach, squeezing out the highest quality data possible by improving the data’s signal-to-noise ratio,” DeForest said. “We developed new filtering algorithms, designed and tested to delineate the true corona from the noisy measurements.”

The algorithms filtered out light and adjusted brightness. But the most challenging obstacle is inherent: blur due to the motion of the solar wind. “This technique adjusted images not just in space, not just in time, but in a moving coordinate system,” DeForest said.

“That allowed us to correct motion blur not just by the speed of the wind, but by how rapidly features changed in the wind.”

With the resulting unprecedented view of the corona, the team made several groundbreaking discoveries. For example, coronal streamers – magnetic loops that can erupt into coronal mass ejections that send blobs of solar material into space – are far more structured than previously thought.

“What we found is that there is no such thing as a single streamer,” DeForest said. “The streamers themselves are composed of myriad fine strands that, together, average to produce a brighter feature.”

Then there’s the theoretical Alfven surface – a proposed surface, or sheet-like layer where the gradually accelerating solar wind reaches a critical speed. But that’s not what DeForest’s team observed.

“What we found is that there isn’t a clean Alfven surface,” DeForest said. “There’s a wide ‘no-man’s land’ or `Alfven zone’ where the solar wind gradually disconnects from the Sun, rather than a single clear boundary.”

And the close look at the coronal structure also raised new questions. Techniques used to estimate the speed of the solar wind revealed that the wind suddenly changes its character at a distance of around 10 solar radii, well within the conventional boundary of the corona itself.

“Some interesting physics is happening around there,” DeForest said. “We don’t know what it is yet, but we do know that it is going to be interesting.”

These first observations will provide key insight for NASA’s upcoming Parker Solar Probe, the first-ever mission to gather measurements from within the outer solar corona.

Catching Them In The Act: Hyper Fast Camera Captures Atoms In Motion

An extremely fast “electron camera” at the Department of Energy’s SLAC National Accelerator Laboratory has produced the most detailed atomic movie of the decisive point where molecules hit by light can either stay intact or break apart.

The results could lead to a better understanding of how molecules respond to light in processes that are crucial for life, like photosynthesis and vision, or that are potentially harmful, such as DNA damage from ultraviolet light.

In the study, published in Science, researchers looked at a gas whose molecules have five atoms each. They watched in real time how light stretched the bond between two atoms in the molecules to a “point of no return,” sending the molecules on a path that either further separated the atoms and cleaved the bond or caused the atoms to vibrate while preserving the bond.

“The starting and end points of a chemical reaction are often obvious, but it’s much more challenging to take snapshots of the rapid reaction steps in between,” said postdoctoral researcher Jie Yang, the study’s lead author from SLAC’s Accelerator Directorate and the Stanford PULSE Institute.

“The crossroads where a molecule can do one thing or another are an important factor in determining the outcome of a reaction. Now we’ve been able to observe directly for the first time how the atomic nuclei of a molecule rearrange at such an intersection.”

Co-author Todd Martinez, a professor at SLAC and Stanford University and an investigator at PULSE, said, “The system we studied is a paradigm for the much more complex light-driven reactions in nature.” For example, the absorption of ultraviolet light can cause damage to DNA, but other mechanisms turn the light’s energy into molecular vibrations and minimize the harmful effect.

Ultra-High-Speed Snapshots of Atoms in Motion
The first steps in light-driven reactions are extremely fast. Molecules absorb light almost instantaneously, leading to a rapid rearrangement of their electrons and atomic nuclei. To see what happens in real time, researchers need ultra-high-speed cameras that can “freeze” motions occurring within femtoseconds, or millionths of a billionth of a second.

The camera used in the study was an instrument for ultrafast electron diffraction (UED), in which a high-energy beam of electrons probes the interior of a sample, generating snapshots of its atomic architecture at different points in time during a chemical reaction. Strung together, these snapshots turn into a movie of the speedy atomic motions.

At SLAC, the researchers flashed laser light into a gas of trifluoroiodomethane molecules and observed over the course of hundreds of femtoseconds how bonds between carbon and iodine atoms elongated to a point at which the bond either broke, splitting off iodine from the molecules, or contracted, setting off vibrations of the atoms along the bond.

“UED was absolutely crucial to seeing that point during the reaction,” said physicist Xijie Wang, head of SLAC’s UED program and the study’s principal investigator. “Other methods either don’t detect nuclear motions directly or haven’t reached the resolution necessary to make this kind of observation in gases.”

Mapping Energy Landscapes of Chemical Reactions
The observation is in agreement with calculations that provide a deeper understanding of what happens during the reaction.

The laser light “energizes” the molecules, elevating them from a low-energy ground state to a higher-energy excited state (see image below). Molecular states like these can be described by energy landscapes, with mountains of more energy and valleys of less energy. Like a golf ball rolling on a curved putting green, the molecules can follow reaction paths on these surfaces.

When the landscapes of different molecular states intersect, the reaction can proceed in several directions. Chemists call this point a conical intersection.

In fact, molecules at conical intersections exist in several states at once – an oddity rooted in the fact that molecules are tiny quantum systems, said co-author Xiaolei Zhu, a postdoctoral researcher at PULSE and Stanford. “We can predict this behavior in computer simulations,” he said. “Now we’ve also directly seen that the molecules behave exactly that way in the experiment.”

The team is now planning the next steps. “We’re continuing to develop the UED method so that we can look at similar processes in liquids,” Wang said. “This will bring us even closer to understanding light-driven chemical reactions in biological environments.”

The TED Conference On Big Ideas Is Putting Its Money Where Its Mouth IsIs

The big-idea Technology, Entertainment and Design (TED) Conference is now backing up its talk on world-changing innovations with big money.

The organizers of the conference known for deep thinking discussions announced Wednesday it has raised $400 million for projects with “the potential to create massive, global change.”

The new initiative known as the Audacious Project will replace the annual $1 million TED prize awards which have been allocated since 2005, with a hefty bump in funding.

TED organizers say the project will fund “collaborative philanthropy for bold ideas” and announced the first awards to organizations working on innovative ideas for health care, justice, agriculture and the environment.

“In some ways, it’s the most ambitious thing TED has ever been involved with,” TED curator Chris Anderson said before taking to the stage to announce the project in Vancouver.

“It’s like trying to recreate what an IPO does, but instead of investing in shares to make money we are investing in dreams to make change.”

Inside TED, they coined the acronym “APO,” for Audacious Project Offering.

Anderson has encouraged TED’s influential community to act on big ideas that win their hearts or minds at annual conferences.

Each year, the project will identify up to five ideas that stand out as “thrillingly bold” with a credible path to execution.

Laurene Powell Jobs, the widow of legendary Apple co-founder Steve Jobs, took to the TED stage to help unveil the project, saying it could change millions of lives for the better by turning bold ideas for good into action.

“We must dream alongside and amplify those voices,” she told the TED audience.

TED said pledges for the project came from Skoll Foundation, Virgin Unite, Dalio Foundation, The Bridgespan Group and others.

– Oceans to Heavens –

The slate of those being backed by the project consisted of The Environmental Defense Fund; The Bail Project; GirlTrek; Sightsavers, and Woods Hole Oceanographic Institution.

US-based Bail Project will manage a nationwide fund to help people post bond to get out of jail while their guilt or innocence is determined.

The Environmental Defense Fund wants to track methane pollution from space with a network of satellites.

“Cutting methane emissions from the global oil and gas industry is the fastest thing we can do right now to put the brakes on climate change,” said EDF president Fred Krupp.

The Woods Hole institution plans to uncover the secrets of a mysterious layer of ocean some 200 to 1,000 meters (600 to 3,000 feet) deep considered integral to the marine food ecosystem and the earth’s climate.

GirlTrek in the US will train activists to improve the health of black women by getting them walking more.

Sightsavers aims to eliminate trachoma, a treatable disease that can blind people and remains a bane in low-income communities.

“We are in a moment where humans more than ever what to change the future,” Anderson said.

“The money is out there; people want to spend it on good ideas.”

– Daring to dream –

Anyone in the world is free to pitch their dreams online at an audaciousproject.org website with a handful picked annually, according to TED.

“We are looking for projects that are capable of impacting at least millions of lives in some way, or at a planetary scale,” Anderson said.

“Almost the single biggest hope is that this process unlocks dreams that entrepreneurs never dared put forward before.”

Since starting as an intimate gathering on the California coast 34 years ago, TED has grown into a global media platform with a stated devotion to “ideas worth spreading.”

TED has a massive following for its trademark presentations in which speakers strive to give “the talk of their lives” in 18 minutes.

The theme of the annual TED conference this week in Vancouver is “Age of Amazement,” but with a keen eye on unintended consequences.