One of my life’s goals is to visit all of our National Park Service’s 401 units — national parks, national monuments, national battlefields, military parks, historical parks, national historic sites, national lakeshores and seashores, national recreation areas and national scenic rivers and trails.

So far, I’ve made it to 273, including all of Georgia’s 10 national parks. Last week, on a trip with my wife to Idaho, Wyoming and Montana, I visited two more units for the first time — Craters of the Moon National Monument, Idaho, one of the best-preserved volcanic lava fields in the United States; and the Big Hole National Battlefield, Mont., where in August 1877 U.S. cavalry troops fought Nez Perce Indians in the biggest battle of the five-month conflict known as the Nez Perce War.

And even though we had visited Grand Teton and Yellowstone National Parks three times previously, we returned to them again — our first visit to them in 22 years. Although I thought that Grand Teton’s high glaciers seemed to have shrunk since our last visit, I nevertheless found the parks to be just as wild, scenic and spellbinding as ever.

At a prominent spot overlooking a valley in Yellowstone, we came upon a group of people who had been sitting and waiting for hours to get a glimpse of gray wolves returning to their den for the evening.

Yellowstone, of course, is America’s first national park, established in 1872 — an icon of the entire National Park Service and a mecca for those of us who revere our national parks.

Mystery writer Nevada Barr, a former park ranger whose novels are set in national parks, sums up in Sierra Club Magazine the feelings of many park lovers: “Our (national) parks are the home of our wildness, our pioneer spirit. Seeing them we know we can do much, go far, withstand the harshest punishment. We know we can make it; we can survive and thrive and flourish.”

Georgia’s national parks include: Chattahoochee River National Recreation Area; MLK Jr. National Historic Site; Jimmy Carter NHS; Andersonville NHS; Fort Pulaski National Monument; Fort Frederica NM; Ocmulgee NM; Cumberland Island National Seashore; Kennesaw Mountain National Battlefield Park; Chickamauga and Chattanooga National Military Park. Also managed by the park service is the 2,184-mile-long Appalachian Trail, which begins in Georgia.

IN THE SKY: The moon will be last quarter on Saturday night — rising just after midnight and setting around midday, said David Dundee, Tellus Science Museum astronomer. Mercury and Venus are low in the west just after dark. Venus sets about an hour after sunset. Saturn is high in the east just after dark. Jupiter and Mars are too close to the sun for easy observation.