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Paul Knightly
June 28, 2018
This image set of NASA's Mars Reconnaissance Orbiter shows a fierce dust storm that rises on Mars, with rovers on the surface indicated as icons.
Image and Caption Credit: NASA / JPL-Caltech / MSSS
While a global dust storm is jeopardizing the rover Opportunity and encircles March, scientists are beginning to s & # 39; 39, interest in the rare phenomenon. The data gathered from this rare atmospheric event could also help provide important clues as NASA develops crew landing plans on the surface of the red planet
. When Mariner 9 arrived in 1971 as the first spacecraft to orbit around the planet, he was treated to an already-ongoing global dust storm that delayed imaging operations and science of nearly two months. The dust storms were monitored by the landing gear and the orbiter Viking however the nuclear powered undercarriages were not affected by the reduction of the sunlight as Opportunity knows. A global dust storm in 2001 was closely monitored by Mars Global Surveyor from the orbit and provided scientists with their best appearance on the date of formation and evolution of the storms of dust
. Spirit Spirit and Opportunity rovers to the test. However, the conditions of the sky have never been bad enough to force either rover to enter protection mode as Opportunity suggests. Almost 6 years have pbaded since the last event. a year has pbaded since scientists published a forecast 2016 that a global dust storm could occur in early 2017. Although this is not a terrible prediction for a planet without the vast network of weather stations and satellites. Earth, it raises the question of what causes these events and makes them difficult to predict?
WHAT CAUSES WORLD DUST STORMS?
World dust storms were probably observed by astronomers in the 1870s, but very few could be verified before the beginning of the space age. Since the dust storm of Mariner 9 in 1971, large dust storms have often been observed during the summer of the southern hemisphere, but they do not occur all the years of March. On average, Mars experiences a global storm every 5 1/2 Earth years (or about every 3rd March). The most recent confirmed global storms occurred in 1977, 1982, 1994, 2001 and 2007, although orbital coverage was limited from the early 1980s to the mid-1990s and the total number of storms could have been higher. . Mars Orbiter Camera on Mars Global Surveyor orbiter of NASA shows a dramatic change in the appearance of the planet when the haze raised by dust storm activity in the south has become globally distributed. The images were taken about a month apart. Credit: NASA / JPL-Caltech / MSSS "width =" 1280 "height =" 682 "/>
Two 2001 images from the Mars Orbiter camera on NASA's Mars Global Surveyor orbiter show dramatic change in the appearance of the planet when the haze raised by the activity of dust storms in the south is globally distributed.The images were taken about a month apart.Secret photo: NASA / JPL-Caltech / MSSS
Regional dust storms are much more common and global storms usually start with a single regional storm or a series of several regional storms.While the precise trigger that causes the storms to expand in a global event is not clear, scientists have a pretty good understanding of the processes that form smaller storms .
It is believed that dust is in the atmosphere Martian weather sunlight warms the air near the surface, causing it to rise in the cooler air above. These updrafts work the same way as their cousins on Earth, but if a current on Mars is strong enough, it can also drop fine dust in the air with it. This is sometimes manifested in the form of dust devils that have been observed by the rovers.
As on Earth, winds on the surface of Mars can be driven by large differences in temperature gradients. Over much of the surface, daytime to nighttime temperatures can range from 100 degrees Celsius or higher. Although in the low pressure atmosphere of Mars (only about 1 percent of the Earth), these result in relatively weak winds that occur in the evening and in the morning. For stronger winds, a larger temperature gradient during daytime heating is required, and this effect is increased in areas where the lower and upper altitudes are close.
The time generated by mountain ranges on Earth is a common phenomenon. summer thunderstorms and generating large amounts of snowfall during the winter. A similar effect was noted on Mars because some areas are more susceptible to recurring dust storms than others because of the relief or proximity of the polar ice caps. These storms usually occur at regular intervals under favorable conditions, especially during the local summer.
For example, the largest variety of topographic relief on Mars is found in the southern hemisphere and includes the lowest point on the planet in the Hellas Basin. At more than 26,000 feet (7,924 meters) below the reference level (or "sea level") for Mars, the deepest parts of Hellas experience some of the highest atmospheric pressures on Mars. This allows to increase temperatures during daytime heating and higher temperature gradients with nearby mountains than is possible elsewhere. As a result, dust storms often originate from the Hellas Basin.
Higher temperature gradients between cooler uplands and warmer lowlands result in stronger winds that can blow dust into the atmosphere. If multiple storms occur simultaneously, the volume of collective dust in the atmosphere may be sufficient to cause a generalized regional storm. What causes the evolution of regional storms in world events is a source of continuing investigation for scientists
IMPACT OF THUNDERSTORMS ON ASTRONAUTS
The opening scene of The film adaptation of Andy Weir's novel involves a dust storm forcing the evacuation of a surface crew and blocking one of their teammates, Mark Watney, on Mars in the process. The scene portrays a dust storm with what appears to be hurricane force winds that threaten to upset the lander and impinge Mark Watney with an antenna that is freeing themselves from their habitat. Although the storm plays a crucial role in the rest of the story, the severity of the storm has not been observed on Mars so far.
Because of the lower air pressure on Mars, a wind of 60 miles (96 km / h) exerts far less force than it would on Earth, perhaps just enough to wave a flag. Even during the strongest winds that Mars can generate, the overall risk for the physical integrity of spacecraft is quite low. Thus, the impacts of a dust storm as described in The Martian are unlikely. However, dust storms will likely have an impact on the missions of astronauts exploring the surface of Mars.
Operational conditions for crewed missions include reduced visibility making EVA dangerous and increasing the amount of dust carried into the spacecraft by astronauts. Concerns also exist regarding the possible build-up of static electricity and electric shocks that could pose a threat to critical spacecraft systems. If one of the space systems relies on solar energy (such as the rover Opportunity ), astronauts may need to shut down noncritical systems and reduce intensive activities until they reach the end of their life. the sky improves
FORECAST FUTURE EVENTS
As with the Earth's weather forecast, the prediction of dust storms on Mars will become easier as more data is collected. on these events. In this regard, the current dust storm is likely to be the world's most studied event on Mars so far. In total, six spacecraft monitor the planet from the orbit and the nuclear power Curiosity rover daily monitors the changing conditions of the sky on the surface. Even Opportunity provided valuable data before shutting himself down as he returned observations on the amount of dust in the atmosphere before the sky became too dark to recharge his batteries
Storm in Utopia Planitia on Mars imaged by Mars Color Imager (MARCI) on Mars Reconnaissance Orbiter in 2007. Image Credit: NASA / JPL / Malin Science Space Systems)
MAVEN NASA (Atmospheric Mars and Volatile EvolutioN) and the ExoMars Trace Gas orbiter from ESA monitor the storm closely to help answer unanswered questions about how dust storms affect elements traces and compounds in the atmosphere. Instruments on other spacecraft, including the Mars Climate Sounder (MCS) and Mars Color Imager (MARCI) on Mars Reconnaissance Orbiter (MRO) also collect daily surface and atmospheric measurements of the storm.
The weekly meteorological bulletins for Mars transmitted to the mission teams were published by Malin Space Science Systems since the arrival of MRO at the end of 2007. These weather reports help mission planners to program the missions. space operations accordingly and predict future events. limited extension. In the future, these weather reports will also help monitor the atmosphere as dust clears over the next few months.
Scientists gain new information from observations of the current storm, improvements can be made to existing climate models. can be used to predict the next big event. By then, 2018 will enter the history books as the most recent global dust storm (if not late) to have an impact on Mars.
Marked: Curiosity Dust Storm March Opportunity The Range
Paul Knightly
Paul is currently a graduate student in Space and Planetary Science at the University of Akransas in Fayetteville. He grew up in the Kansas City area and began to take an interest in space at a young age at the start of the Twin Mars Exploration Rover missions in 2003. He began his aerospace engineering studies before moving on to at geology at Wichita State University where he earned a BSc in 2013. After working as an environmental geologist for a civil engineering firm, he began his graduate studies in 2016 and is actively working on a PhD that will focus on surface process of Mars. He also participated in a two-week simulation at Mars Society's March Desert Research Station in 2014 and remains involved in badog mission studies today. Over the years, Paul has been interested in science outreach and communication. He has notably held a personal blog on high school space exploration during his undergraduate career and has lectured in schools and other organizations. space. He is delighted to bring his experience as a geologist and scientist to the Spaceflight Insider team that writes primarily on space science topics.
