Mars' Opportunity rover continues to be stuck in the heart of a weeks-long dust storm that has grown massive enough to encircle the entire planet.

Even worse, almost a month since it began, the storm shows no signs of clearing anytime soon.

Opportunity Stays Silent As Dust Storm Intensifies

The dust storm was first detected on Wednesday, May 30, but it soon swelled to be bigger than the North America continent.

Now, Bruce Cantor of the Malin Space Science Systems says that the storm has progressed to a "planet-encircling" or global dust event, NASA reports.

The 15-year-old Opportunity rover, which is hunkered down in Mars' Perseverance Valley, have been silent despite scientists keeping an ear out for a signal. While the rover is not expected to communicate until the Martian skies have cleared up, the team continues to monitor and listen for a signal daily.

Last June 12, NASA engineers tried to communicate with the Opportunity rover but did not receive a response. It is assumed that the rover's batteries have a charge that's under 24 volts, which puts the spacecraft in low power fault mode. In this state, all the subsystems except the mission clock are shut down.

The mission clock wakes the computer periodically to monitor power levels. If there's not enough charge in the batteries, it goes back into sleep mode.

The Challenges For Opportunity

The Opportunity rover has survived in Mars for nearly 15 years despite being designed for a 90-day period, so it's safe to say that this is a spacecraft that's tough and resilient. However, this powerful storm is challenging the rover, as it blots out the sun and keeps the solar-powered batteries of the Opportunity from charging.

So far, scientists are hopeful that it will survive. An analysis of Opportunity's survivability came back positive, with the team determining that the electronics and batteries can keep warm enough to continue its functions.

Once the dust settles from the atmosphere, another potential threat is too much of the particles coating the rover and damaging some of its equipment.

Mars' Dust Storms

Massive storms are quite rare in Mars, but dust storms happen roughly the same time every year during early spring to summer. Heat, after all, is what propels these storms in the Red Planet.

"If you have sunlight that reaches the surface and heats it up, that creates an instability where warm air rises up. On Mars, there's so much of this loose dust lying on the surface that when you have these upward winds, they take a lot of the dust with it," Tanya Harrison, a planetary scientist at the Arizona State University, explains to Popular Science.

Sand in Mars are considerably finer and smaller than the ones on Earth, so it can hang in the air for a very long time.

This isn't the first massive dust storm that's been closely observed on Mars, but NASA says this current one is patchier and more diffused instead of obscuring the Red Planet's surface completely. This makes the storm's development unpredictable, and it doesn't seem to be clearing out soon.