Readers ask about Mars dust storms, Fermi bubbles and more
Mars dust up
Predicting dust storms on Mars will help keep rovers and future astronauts safe on the planet’s surface, Lisa Grossman reported in “How upcoming missions to Mars will help predict its wild dust storms” (SN: 7/4/20 & 7/18/20, p. 24).
The story reported that scientists struggle to understand how dust gets lifted into the air. “Have they considered static electricity? A static charge on the dust particles would create repulsion between separate particles and between particles and the ground, levitating them enough to be moved by the winds,” reader Bruce Merchant wrote.
Yes, electric fields formed by colliding dust grains can help increase the amount of dust in the atmosphere. Though electric forces alone are not enough to explain dust lift on Mars, the forces “are critical in the dust-lifting process and should be taken into account,” says Germán Martínez of the Lunar and Planetary Institute in Houston. Electric forces also loft dust into Earth’s atmosphere, Grossman notes. Studies in the Moroccan desert have suggested that electric fields can increase the amount of dust injected into the atmosphere by a factor of 10.
Merchant thought static electricity could have contributed to the demise of NASA’s Phoenix Mars Lander and Mars Exploration Rover Opportunity. “Do any current or planned missions to Mars include sensors that could detect and measure static electrical activity?” he asked.
Electric fields associated with dust lifting could affect the performance and lifetime of hardware on Mars, Grossman says, “although I don’t think it was the critical factor for Phoenix or Opportunity.” No past mission has measured electric fields, nor will any of the three missions launched in 2020. The European Space Agency’s Schiaparelli lander was supposed to take such measurements, but the lander crashed into the Red Planet in 2016. The ExoMars mission lander slated to launch in 2022 will measure electric fields. “That’ll be a precious piece of information,” Martínez says.
Red Planet preppers
Future Mars explorers will need protections from microgravity and radiation, Maria Temming reported in “What will astronauts need to survive the dangerous journey to Mars?” (SN: 7/4/20 & 7/18/20 p. 18).
Reader Henry Jones wondered if a protective magnetic field could be created to surround a Mars-bound spaceship.
NASA is investigating whether it’s possible to build a device that would generate a magnetic field to repel radiation, as Earth’s magnetic field does. The idea “is in its infancy,” says Jennifer Fogarty, chief scientist of NASA’s Human Research Program at Johnson Space Center in Houston. “We’re all rooting for it.… It would be amazing for something like that to arrive. I can’t depend on it, though.”
Gassy with a chance of bubbles
Scientists spotted visible light emanating from gas blobs, called Fermi bubbles, that sandwich the plane of the Milky Way galaxy, Emily Conover reported in “The Milky Way’s giant gas bubbles were seen in visible light for the first time” (SN: 7/4/20 & 7/18/20, p. 5).
“Has there been a survey of Fermi bubbles around other galaxies?” reader Eric Anderson asked.
Yes, researchers have looked for Fermi bubbles around nearby galaxies, Conover says, but the bubbles are not easy to spot. “There is some evidence for bubbles around the neighboring Andromeda galaxy, about 2.5 million light-years away,” she says.
What’s in a name?
Astronomers identified two unusual bursts of light, one known as CSS161010 and the other nicknamed the Koala, Emily Conover reported in “A weird cosmic flare called the ‘Cow’ now has company” (SN: 7/4/20 & 7/18/20, p. 12).
“A ‘cute’ nickname for CSS161010 would be Tenten, for the obvious reason, but also because (thanks to a Google search) it is the name of a female character in [the] Japanese manga series … Naruto,” reader Oliver Del Signore wrote. “If Tenten or some other nickname is eventually assigned, I hope Science News will include a short update in a future issue.”