Last week saw the discovery of what scientists call "the God particle," which is the subject of tonight's "Through the Wormhole With Morgan Freeman" (9 p.m., Science, TV-PG), the first episode of the fourth season.

I'm certainly among those who need somebody to explain just what it all means.

From what I've read, it seems that the discovery of this particle confirms a theory that has been around for nearly 50 years, and that the search for Higgs boson is the reason behind the billions of dollars spent by scientists at the European Organization for Nuclear Research over the past several decades. For particle physicists, this is like the moon landing.

Apparently, the discovery helps explain some mysteries at the center of existence, such as how particles of any sort acquire mass. But according to the teaser for "Wormhole," the momentous event may raise as many questions as it settles.

---Turner Classic Movies spends the night on the moon and beyond the stars with five consecutive movies set in outer space. The 1989 documentary "For All Mankind" (8 p.m.) recalls the Apollo missions to the moon.

Four fictional films follow: the sequel to "2001: A Space Odyssey," "2010" (9:30 p.m.), which wasn't directed by Stanley Kubrick; the 1956 fantasy "Forbidden Planet" (11:30 p.m.); "20 Million Miles to Earth" (1:30 a.m.); and the 1969 thriller "Marooned" (3 a.m.), starring Gregory Peck.

OTHER HIGHLIGHTS

---The Huntress returns on "Arrow" (8 p.m., CW, TV-14).

---"KKK: Beneath the Hood" (8 p.m., Discovery, TV-14) looks at the Ku Klux Klan in the 21st century.

---Jack Nicholson stars in director Stanley Kubrick's "The Shin ing" (8 p.m., BBC America).

---Cassidy faces allegations on "Law & Order: Special Victims Unit" (9 p.m., NBC, TV-14).

---Gang-related shootings on "Boston's Finest" (9 p.m., TNT, TV-14).

---A couple seeks a green home on "Property Brothers" (9 p.m., HGTV, TV-G).

---Death crowns a prom queen on "CSI" (10 p.m., CBS, TV-14).

---Mills confronts Bernie about the fire that killed his father on "Chi cago Fire" (10 p.m., NBC, TV-14).

---Lydia unravels on "South land" (10 p.m., TNT, TV-MA).

---Pursuing the same man on "The Americans" (10 p.m., FX, TV-MA).

---A spat with neighbors on "Weed Country" (10 p.m., Discovery, TV-14).

---Tensions mount at a shoe sale on "Dukes of Melrose" (10:30 p.m., Bravo).

---Shawn seeks guy time with Juliet's stepfather on "Psych" (10 p.m., USA, TV-PG).

CULT CHOICE

Two slackers (Bill Murray and Harold Ramis) find themselves in the Army in the 1981 comedy "Stripes" (8 p.m., VH1 Classic).

SERIES NOTES

---Bethenny Frankel guest stars on "The Neighbors" (8:30 p.m., ABC, TV-PG).

---Social networking can be murder on "Criminal Minds" (9 p.m., CBS, TV-14).

---Another demon on "Super natural" (9 p.m., CW, TV-14).

---Dallas frets on "Suburga- tory" (9:30 p.m., ABC, TV-14).

LATE NIGHT

---Steven Brill is scheduled on "The Daily Show With Jon Stew art" (11 p.m., Comedy Central, r).

---Mel Brooks appears on "Conan" (11 p.m., TBS, r).

---Gerard Butler and Heather McDonald are booked on "Chelsea Lately" (11 p.m., E!).

---James Franco sits down on "The Colbert Report" (11:30 p.m., Comedy Central, r).

---Graham Rahal and the Airborne Toxic Event appear on "Late Show With David Letterman" (11:35 p.m., CBS).

---Jay Leno welcomes Vanessa Hudgens, Chris O'Dowd and Gary Clark Jr. on "The Tonight Show" (11:35 p.m., NBC).

---Elle Fanning appears on "Jimmy Kimmel Live" (11:35 p.m., ABC).

---Rudy Giuliani and Judd Apatow visit "Late Night With Jimmy Fallon" (12:35 a.m., NBC).

---Craig Ferguson hosts Aaron Eckhart and Kellie Pickler on "The Late Late Show" (12:35 a.m., CBS).

Kevin McDonough can be reached at kevin.tvguy@gmail.com.