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Written by: Anna Blaustein

Published: 17 October 2021

Asteroids embody the story of our solar system’s beginning. Jupiter’s Trojan asteroids, which orbit the Sun on the same path as the gas giant, are no exception.

The Trojans are thought to be left over from the objects that eventually formed our planets, and studying them might offer clues about how the solar system came to be.

Over the next 12 years, NASA’s Lucy mission will visit eight asteroids — including seven Trojans — to help answer big questions about planet formation and the origins of our solar system. It will take the spacecraft about three and a half years to reach its first destination. What might Lucy find?

Like all the planets, asteroids exist in the heliosphere, the vast bubble of space defined by the reaches of our Sun’s wind. Directly and indirectly, the Sun affects many aspects of existence within this pocket of the universe. Here are a few of the ways the Sun influences asteroids like the Trojans in our solar system.

Place in space

Asteroids embody the story of our solar system’s beginning. Jupiter’s Trojan asteroids, which orbit the Sun on the same path as the gas giant, are no exception. The Sun makes up 99.8% of the solar system’s mass and exerts a strong gravitational force as a result. In the case of the Trojan asteroids that Lucy will visit, their very location in space is dictated in part by the Sun’s gravity.

They are clustered at two Lagrange points. These are locations where the gravitational forces of two massive objects — in this case the Sun and Jupiter — are balanced in such a way that smaller objects like asteroids or satellites stay put relative to the larger bodies. The Trojans lead and follow Jupiter in its orbit by 60° at Lagrange points L4 and L5.

Pushing asteroids around (with light!)

That’s right, sunlight can move asteroids! Like Earth and many other objects in space, asteroids rotate.

At any given moment, the Sun-facing side of an asteroid absorbs sunlight while the dark side sheds energy as heat. When the heat escapes, it creates an infinitesimal amount of thrust, pushing the asteroid ever so slightly off its course.

Over millions of years, this force, called the Yarkovsky effect, can noticeably alter the trajectory of smaller asteroids (those less than 25 miles, or about 40 kilometers, in diameter).

Similarly, sunlight can also alter the rotation rate of small asteroids. This effect, known as YORP (named for four scientists whose work contributed to the discovery), affects asteroids in different ways depending on their size, shape, and other characteristics.

Sometimes, YORP causes small bodies to spin faster until they break apart. Other times, it may cause their rotation rates to slow.

The Trojans are farther from the Sun than the near-Earth or Main Belt asteroids we’ve studied before, and it remains to be seen how the Yarkovsky effect and YORP affect them.

Shaping the surface

Just like rocks on Earth show signs of weathering, so too do rocks in space, including asteroids. When rocks warm up during the day, they expand. As they cool down, they contract. Over time, this fluctuation causes cracks to form. The process is called thermal fracturing.

The phenomenon is more intense on objects without atmospheres, such as asteroids, where temperatures vary wildly. Therefore, even though the Trojans are farther from the Sun than rocks on Earth, they’ll likely show more signs of thermal fracturing.

The lack of atmosphere has another implication for asteroid weathering: Asteroids are battered by the solar wind, a steady stream of particles, magnetic fields, and radiation that flows from the Sun.

For the most part, Earth’s magnetic field protects us from this bombardment. Particles that do get through can excite molecules in Earth’s atmosphere, resulting in auroras.

Without magnetic fields or atmospheres of their own, asteroids receive the brunt of the solar wind.

When incoming particles strike an asteroid, they can kick some material off into space, changing the fundamental chemistry of what’s left behind.

Anna Blaustein works for NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

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Written by: Elizabeth Larson

Published: 16 October 2021

LAKE COUNTY, Calif. — The Lake County Registrar of Voters Office has completed the official canvass for last month’s special gubernatorial recall election and will present the final results to the Board of Supervisors on Tuesday.

The special election seeking Gov. Gavin Newsom’s recall took place on Sept. 14. It was the 54th unsuccessful recall attempt against a governor since 1913.

The official canvass must be completed within a month, and Registrar of Voters Maria Valadez completed her work on Thursday, as planned.

The results will be certified by Oct. 22, the Secretary of State’s Office reported.

Valadez will ask the supervisors to adopt a resolution accepting the official canvass and accept her certification of the election results, which will be taken up as part of the consent agenda.

The final results for Lake County showed that there was a 59.59% percent voter participation rate, with 22,388 ballots cast over 70 precincts. There are 37,571 registered voters in the county.

The ballots cast in favor of recalling Gov. Newsom totaled 10,923, or 49%, while the no votes totaled 11,367, or 51%.

That’s compared with the initial count given on the night of Sept. 14, when the early returns looked far more lopsided.

The preliminary results on that night showed a 62.48% “no” vote compared to a 37.52% “yes” vote, as Lake County News has reported. At that point 9,333 of the 22,388 ballots had been counted, accounting for 41% of the total vote.

In a breakdown of vote-by-mail or absentee ballots, the yes vote was 47.06%, or 9,647 ballots, to 10,851 no votes, or 52.94%.

Of those ballots cast on Election Day, 71.21%, or 1,276 ballots, supported the recall, while 516 ballots, or 28.79%, voted against the recall.

The top five candidates who received votes to succeed Newsom had he been recalled were led in Lake County by Larry Elder, with 6,306 votes; John Cox, 1,060 votes; Kevin Kiley, 801 votes; Kevin Paffrath, 642 votes; and Patrick Kilpatrick, 548 votes.

While Lake County’s final results were markedly different from the preliminary count, on a statewide basis, the statewide results changed slightly.

Early on Sept. 15, the California Secretary of State’s Office reported that the preliminary statewide count was 63.9% against the recall and 36.1% in support of it.

On Friday, the Secretary of State’s Office said the statewide results were 61.9% against the recall and 38.1 percent for it.

Statewide, in the top five Elder also led alternate candidates, followed by Paffrath, Kevin L. Faulconer, Brandon M. Ross and Cox.

The state results can be found here.

Email Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it.. Follow her on Twitter, @ERLarson, or Lake County News, @LakeCoNews.

091421 Certification of County Elections Official of Results by LakeCoNews on Scribd

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Written by: Elizabeth Larson

Published: 16 October 2021

LAKE COUNTY, Calif. — Firefighters worked early Saturday to contain a fire involving several structures in the Kelseyville area.

Shortly after 2:45 a.m., several structures were reported to be on fire at 9495 Konocti Bay Road, near Richmond Park Bar & Grill.

Firefighters arriving on scene reported that there were two motor homes fully involved, with a third trailer becoming involved a short time later, according to radio traffic.

The fire also was reported to have moved into nearby vegetation.

The Northshore Fire Support Team was requested to respond to the scene.

Incident command asked for Pacific Gas and Electric to respond, as well as asking for a hand crew.

Just before 4:15 a.m., the fire was reported to be confined to the structures, with firefighters working on the vegetation fire.

Firefighters were expected to be on scene until later in the morning for mop up.

Additional information will be published as it becomes available.

Email Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it.. Follow her on Twitter, @ERLarson, or Lake County News, @LakeCoNews.