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By Scott Dance, The Baltimore Sun

BALTIMORE — NASA’s Messenger spacecraft has swung around its namesake planet for three years, beaming observations of Mercury back to Earth, but next March it will smash into the cratered surface it has been studying from afar.

The satellite’s oblong orbit around the solar system’s innermost planet brings it gradually closer and closer as it looks into Mercury’s mysterious volcanoes, craters, and magnetic field. With dwindling fuel to counteract the dense planet’s pull, the scientists managing the mission at Johns Hopkins Applied Physics Laboratory in Laurel can only delay its fall for so long.

It’s now orbiting as close as several dozen miles above the planet’s gray, dimpled crust — and soon, closer. Data collected in the final months of the decade-long mission to explore the inner solar system could help prove the presence of ice in polar craters and provide more detailed accounts of what volatile elements are contained in lava flows or the mysterious depressions on the planet’s surface.

Those “bonus” observations depend on Messenger’s instruments holding up to the 800-degree heat radiating from Mercury’s surface during the slow-rotating planet’s prolonged days. The planet, named for the Roman god of messages, makes one revolution around the sun every 88 Earth days, and yet it rotates so slowly that it takes 176 Earth days for one solar day to pass on Mercury.

As long as the instruments hold up, they could add detail and nuance to data that is expected be used by scientists for decades to come, providing insights into how planetary systems form around stars across the universe.

“Every time we’ve gone somewhere in the solar system and looked with higher resolution, we’ve made new discoveries,” said Larry Nittler, a scientist at the Carnegie Institution for Science who is deputy principal investigator of the $500 million project’s science team.

Since its launch in 2004, Messenger has made plenty of discoveries.

Much of what was known about the planet closest to the sun came from NASA’s Mariner 10 mission, which flew past Mercury and Venus in 1974 and 1975. Mariner found early signs of Mercury’s iron core, small magnetic field, and minimal atmosphere.

Messenger began sending photographs and other observations of the planet in January 2008, eventually cataloging the entire surface for the first time. The closer it got to the planet, the more theories it confirmed and disproved.

When Messenger began an elongated, elliptical orbit around Mercury in 2011, the data were even more dramatic.

Scientists predicted they would find few “volatile” elements — abundant here on Earth but with boiling points too low to be expected to withstand Mercury’s heat — in the planet’s crust. But they found astonishingly high levels of sodium and potassium, as well as surprisingly low levels of iron. They also found signs of significant volcanic activity, perhaps not as distant in the past as once expected.

They mapped its magnetic field and found it to be asymmetrical, unlike Earth’s, with its magnetic equator located about 20 percent of the way toward the pole.

And they believe they have confirmed that some craters at the planet’s poles contain ice — the holes are deep enough to remain in permanent shadow.

“In many cases, a lot of our original ideas about Mercury were just plain wrong,” Nittler told the Baltimore Sun in June 2011, after just three months of data collection in orbit.

Now scientists hope to prove more theories wrong, or right, as the case may be.

A closer view could prove the presence of ice in the polar craters and provide greater detail of what elements are in different geographic features. Images from the first year of orbit showed, at best, 10 meters per pixel, but are now approaching 2 meters per pixel. Observations of magnetic fields and elemental composition are similarly getting increasingly detailed.

One feature scientists are particularly interested in getting a closer look at is what are known as hollows, irregularly shaped depressions with bright, flat floors and halo-like markings around them. They believe a combination of the planet’s heat, its constant bombardment by tiny meteors, and the powerful effects of charged solar particles could be causing materials in surface rocks, likely sulfur or potassium, to sublimate — transforming from solid to gas without first becoming liquid — leaving the curious craters behind.

“We’ve always had to squint at the images to see the details,” said Nancy Chabot, instrument scientist for Messenger’s cameras, the Mercury Dual Imaging System. “We’re getting new insights into the depths of these features and what the edges look like in more detail.”

Any more data the mission is able to collect before Messenger crashes or is fried by the heat will be the last gathered on Mercury for years. Last year, NASA signed on to the European Space Agency’s BepiColombo mission, which plans to send two spacecraft to Mercury in 2022 to gather more data on the planet’s composition, core, and magnetic field.

Photo: Baltimore Sun/MCT/Barbara Haddock Taylor

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Eric Holder

The failure of major federal voting rights legislation in the Senate has left civil rights advocates saying they are determined to keep fighting—including by suing in battleground states. But the little bipartisan consensus that exists on election reform would, at best, lead to much narrower legislation that is unlikely to address state-level GOP efforts now targeting Democratic blocs.

“This is the loss of a battle, but it is not necessarily the loss of a war, and this war will go on,” Eric Holder, the former U.S. attorney general and Democrat, told MSNBC, saying that he and the Democratic Party will be suing in states where state constitutions protect voting rights. “This fight for voting rights and voter protection and for our democracy will continue.”

“The stakes are too important to give up now,” said Damon Hewitt, president and executive director of the Lawyers’ Committee for Civil Rights Under Law, which for years has operated an Election Day hotline to help people vote. “Our country cannot claim to be free while allowing states to legislate away that freedom at will.”

In recent weeks, as it became clear that the Senate was not going to change its rules to allow the Freedom to Vote Act and the John Lewis Voting Rights Advancement Act to pass with a simple majority, there have been efforts by some lawmakers, election policy experts, and civil rights advocates to identify what election reforms could pass the Senate.

“There are several areas… where I think there could be bipartisan consensus,” said David Becker, executive director of the Center for Election Innovation and Research, in a briefing on January 20. “These areas are all around those guardrails of democracy. They are all about ensuring that however the voters speak that their voice is heard… and cannot be subverted by anyone in the post-election process.”

Becker cited updating the 1887 Electoral Count Act, which addressed the process where state-based slates of presidential electors are accepted by Congress. (In recent weeks, new evidence has surfaced showing that Donald Trump’s supporters tried to present Congress with forged certificates as part of an effort to disrupt ratifying the results on January 6, 2021.) Updating that law could also include clarifying which state officials have final authority in elections and setting out clear timetables for challenging election results in federal court after Election Day.

Five centrist Washington-based think tanks issued a report on January 20, Prioritizing Achievable Federal Election Reform, which suggested federal legislation could codify practices now used by nearly three-quarters of the states. Those include requiring voters to present ID, offering at least a week of early voting, allowing all voters to request a mailed-out ballot, and allowing states to start processing returned absentee ballots a week before Election Day.

But the report, which heavily drew on a task force of 29 state and local election officials from 20 states convened by Washington’s Bipartisan Policy Center, was notable in what it did not include, such as restoring the major enforcement section of the Voting Rights Act of 1965, which was removed by the U.S. Supreme Court in 2013. It did not mention the Electoral Count Act nor growing threats to election officials from Trump supporters.

“This won’t satisfy all supporters of the Freedom to Vote Act, but this is a plausible & serious package of reforms to make elections more accessible and secure that could attract bipartisan support,” tweeted Charles Stewart III, a political scientist and director of the MIT Election Data and Science Lab. “A good starting point.”

The reason the centrist recommendations won’t satisfy civil rights advocates is that many of the most troubling developments since the 2020 election would likely remain.

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(Reuters) -The prosecutor for Georgia's biggest county on Thursday requested a special grand jury with subpoena power to aid her investigation into then-President Donald Trump's efforts to influence the U.S. state's 2020 election results.

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