California lawmakers voted this summer for strict energy legislation that would require the state’s electricity sources to be 100 percent carbon-free within less than 30 years. The bill, passed by the State Senate and Assembly and signed by Gov. Jerry Brown on Sept. 10, will bump up California’s current mandate, increasing from 50 percent to 60 percent the amount of renewable power generation required in the state by 2030. The ultimate goal: All California electricity would be produced without greenhouse gases by 2045.

Under the law, California will eventually need to get all of its electric energy from sources such as wind, solar, geothermal, and dams. Lawmakers claim they will hash out the specifics later.

Supporters hope the plan will influence the rest of the nation. “We have to show what can be done,” Assemblyman Bill Quirk, a Democrat from Hayward, said in a statement. “If we can get to 100 percent renewables, others will as well.” (So far, only Hawaii has a similar mandate.)

Opponents of the bill, though, warned the goal is unachievable and could sharply increase the cost of energy for businesses, factories, and food processors—costs they will ultimately pass on to consumers. Assemblyman Jim Patterson, a Republican from Fresno, described the bill as “a leap of faith and a gamble,” the Los Angeles Times reported.

The measure elicited the most opposition from Republican lawmakers, but some Democrats voted against it as well. Democratic Assemblyman Adam Gray accused the plan’s proponents of trying to impress progressives across the country rather than considering the poor residents of rural communities who would face higher electricity bills. “This is yet another in a laundry list of bills that are discriminatory to the people I represent,” he said.

Milk advisory

With recreational marijuana legalized in nine states and medical marijuana legalized in 31, doctors report that an increasing number of pregnant and breastfeeding women use the drug. The American Academy of Pediatrics recommends that breastfeeding women refrain from marijuana use, but until now little health research has illuminated the subject.

Now a new study, published online Aug. 27 in Pediatrics, shows that THC, the primary psychoactive chemical in marijuana, not only comes through in a mother’s breast milk but can remain present for up to six days. The researchers found that the active compounds in marijuana easily bind to fat molecules abundant in breast milk. Although THC exposure in the nursing infants measured relatively low, the researchers said that no one knows what constitutes a safe amount. They noted marijuana varieties today contain much more potent compounds than they did 20 or 30 years ago. —J.B.

Tag-along asteroids

Earth’s “mini-moons” may be the next frontier in space, according to a review published May 24 in Frontiers in Astronomy and Space Sciences.

Existing technology has so far identified only one mini-moon, a small asteroid caught in an orbit around the Earth. The speed and small size of mini-moons, only about 3 to 6 feet in diameter, make them hard to detect. But scientists hope the new Large Synoptic Survey Telescope, currently under construction in Chile, will discover many mini-moons orbiting our planet. (The telescope will photograph the entire available sky every few nights.)

Scientists envision capturing the asteroids and studying their composition to learn more about our solar system. —J.B.