New Evidence Suggests Large Water Ice Supply near Mars' Equator
2024-01-29
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1A Mars explorer has discovered new evidence of a large amount of water ice buried near the planet's equator.
2The discovery was made with data collected by the Mars Express orbiter.
3The spacecraft is operated by the European Space Agency (ESA).
4The American space agency NASA is a partner on the orbiter's mission.
5ESA launched Mars Express in 2003 and it has been studying the Red Planet ever since.
6The mission's main goal is to use its seven scientific instruments to search for signs of water underneath the surface of Mars.
7Scientists involved in the new research say data suggesting the presence of newly discovered ice deposits could mean Mars may have once supported life.
8The Mars Express orbiter collected data around an area of the planet known as the Medusae Fossae Formation (or MFF).
9NASA describes this formation as "a soft, easily eroded deposit that extends for nearly 1,000 kilometers along the equator of Mars."
10Scientists believe the MFF was most likely formed by wind-blown dust or volcanic ash.
11The formations could have formed after volcanic activity estimated to have taken place up to 3.8 billion years ago.
12Images of the area show raised areas that scientists thought in the past might contain dust blown around the planet by wind over many years.
13But the new research used newer data collected by the orbiter's MARSIS instrument.
14It is "a subsurface radar sounder" with a 40-meter-long antenna.
15The tool looks for water on the surface, as well as up to five kilometers below the surface.
16The MARSIS instrument is designed to send radio waves to an area scientists choose.
17It then attempts to listen to and examine "echoes" produced by the radio waves.
18The echoes help researchers recognize where water or ice might be, NASA explains.
19Scientists say any water identified near the surface results in stronger signals while the presence of ice or other materials would produce weaker signals.
20The team said MARSIS readings suggest the MFF area of Mars contains a large amount of water ice rather than wind-blown dust.
21Thomas Watters of the U.S. Smithsonian Institution led the new research.
22His team's findings were recently published in a study in Geophysical Research Letters.
23He said in a statement the radar data showed the deposits in the MFF area were even thicker than earlier measurement estimates had shown.
24The researchers said the data showed the examined deposits extended beneath the Mars surface to depths up to 3.7 kilometers.
25They seemed to contain "layers of dust and ice, all topped by a protective layer of dry dust or ash."
26Earlier data examinations of the MFF area found similarities in the electrical properties of deposits there to ice-rich deposits found in the planet's north and south poles.
27The latest MARSIS data strengthens this evidence by suggesting similarities between deposit layering in the MFF and the planet's poles.
28"The radar signals match what we'd expect to see from layered ice," Watters said.
29He added that the radar waves were found to be "similar to signals we see from Mars's polar caps, which we know to be very ice rich."
30It is not the first time scientists have discovered strong evidence for the presence of water ice on Mars.
31But the researchers say the latest study suggests the largest amount of water ever identified in the MFF area.
32They estimated the total amount of water contained there would be enough "to cover the surface of Mars to a depth of about 1.5 to 3 meters."
33Colin Wilson is a project scientist with the Mars Express mission.
34He said while the new finding is exciting, it also "raises as many questions as answers."
35He continued, "How long ago did these ice deposits form, and what was Mars like at that time?"
36Wilson said if confirmed to be water ice, the large deposits "would change our understanding of Mars climate history."
37Watters added that since the discovery was made in an area near the Martian equator, it could be considered a good place for future exploration missions.
38He explained that with a lower elevation, the MFF area would be considered "an ideal landing spot for spacecraft."
39Such an elevation provides more atmosphere to support an effective, controlled landing, Watters said.
40I'm Bryan Lynn.
1A Mars explorer has discovered new evidence of a large amount of water ice buried near the planet's equator. 2The discovery was made with data collected by the Mars Express orbiter. The spacecraft is operated by the European Space Agency (ESA). The American space agency NASA is a partner on the orbiter's mission. 3ESA launched Mars Express in 2003 and it has been studying the Red Planet ever since. The mission's main goal is to use its seven scientific instruments to search for signs of water underneath the surface of Mars. 4Scientists involved in the new research say data suggesting the presence of newly discovered ice deposits could mean Mars may have once supported life. 5The Mars Express orbiter collected data around an area of the planet known as the Medusae Fossae Formation (or MFF). NASA describes this formation as "a soft, easily eroded deposit that extends for nearly 1,000 kilometers along the equator of Mars." 6Scientists believe the MFF was most likely formed by wind-blown dust or volcanic ash. The formations could have formed after volcanic activity estimated to have taken place up to 3.8 billion years ago. 7Images of the area show raised areas that scientists thought in the past might contain dust blown around the planet by wind over many years. But the new research used newer data collected by the orbiter's MARSIS instrument. It is "a subsurface radar sounder" with a 40-meter-long antenna. The tool looks for water on the surface, as well as up to five kilometers below the surface. 8The MARSIS instrument is designed to send radio waves to an area scientists choose. It then attempts to listen to and examine "echoes" produced by the radio waves. The echoes help researchers recognize where water or ice might be, NASA explains. 9Scientists say any water identified near the surface results in stronger signals while the presence of ice or other materials would produce weaker signals. The team said MARSIS readings suggest the MFF area of Mars contains a large amount of water ice rather than wind-blown dust. 10Thomas Watters of the U.S. Smithsonian Institution led the new research. His team's findings were recently published in a study in Geophysical Research Letters. He said in a statement the radar data showed the deposits in the MFF area were even thicker than earlier measurement estimates had shown. 11The researchers said the data showed the examined deposits extended beneath the Mars surface to depths up to 3.7 kilometers. They seemed to contain "layers of dust and ice, all topped by a protective layer of dry dust or ash." 12Earlier data examinations of the MFF area found similarities in the electrical properties of deposits there to ice-rich deposits found in the planet's north and south poles. The latest MARSIS data strengthens this evidence by suggesting similarities between deposit layering in the MFF and the planet's poles. 13"The radar signals match what we'd expect to see from layered ice," Watters said. He added that the radar waves were found to be "similar to signals we see from Mars's polar caps, which we know to be very ice rich." 14It is not the first time scientists have discovered strong evidence for the presence of water ice on Mars. But the researchers say the latest study suggests the largest amount of water ever identified in the MFF area. They estimated the total amount of water contained there would be enough "to cover the surface of Mars to a depth of about 1.5 to 3 meters." 15Colin Wilson is a project scientist with the Mars Express mission. He said while the new finding is exciting, it also "raises as many questions as answers." He continued, "How long ago did these ice deposits form, and what was Mars like at that time?" Wilson said if confirmed to be water ice, the large deposits "would change our understanding of Mars climate history." 16Watters added that since the discovery was made in an area near the Martian equator, it could be considered a good place for future exploration missions. He explained that with a lower elevation, the MFF area would be considered "an ideal landing spot for spacecraft." Such an elevation provides more atmosphere to support an effective, controlled landing, Watters said. 17I'm Bryan Lynn. 18Bryan Lynn wrote this story for VOA Learning English, based on reports from the European Space Agency, NASA, Geophysical Research Letters and the Smithsonian. 19Words in This Story 20equator -n. an imaginary line around the middle of a planet that is an equal distance from its north and south poles 21mission - n. the flight of a spacecraft to perform a certain task or job 22deposit - n. a layer of a substance that has developed from a natural or chemical process 23erode - v. to gradually be damaged over time 24antenna - n. a piece of metal used for receiving television or radio signals 25echo - n. the repeating of a sound caused by the reflection of sound waves 26layer - n. an amount of substance covering a surface 27match - v. to fit together or make suitable for fitting together 28elevation - n. the height of a place above the level of the sea