KEITH URBAN HOSTS the “55th Academy of Country Music Awards” (8 p.m., CBS). For the first time, the ACM awards will be broadcast from Nashville and take place in three separate venues: the Grand Ole Opry House, Nashville’s historic Ryman Auditorium and the Bluebird Cafe.

Even if you’ve never followed country music, you might be familiar with those places from “Nashville,” the soapy musical melodrama that aired on ABC and CMT from 2012-18.

• In other music news, Netflix debuts “Sing On!” an eight-episode karaoke singing competition hosted by Tituss Burgess (“Unbreakable Kimmy Schmidt”).

But for the fact that this can be streamed and “binged,” is this any different from other reality talent contests? Not really. And that’s kind of the point.

The genius of Netflix (or the threat of Netflix, if you’re a traditional broadcaster) is that it’s big enough and sufficiently prolific to own the highbrow as well as the lowbrow, the Emmy-nominated and the guilty pleasure. The sumptuously produced “The Crown” satisfies one TV taste, and shows like “Sing On!” and “Nailed It!” another. And they’re all on the same streaming service.

It’s daunting to admit, but I’ve been writing about television since the late 1990s. And there’s more “TV” on Netflix now than there was “TV” in 1997. That’s slightly terrifying and overwhelming. But it presents viewers with an embarrassment of riches. Or at least choices.

• Also streaming on Netflix, the four-part docu-series “The Challenger: The Final Flight” recalls the seven members of the space shuttle crew who died in an explosion on Jan. 28, 1986. The disaster was particularly traumatic for young people, who were encouraged to watch the launch on television in their classrooms.

“Challenger” profiles each of the crew members lost that day and the extensive search for the cause of the explosion, an investigation that put the shuttle program on hold for years.

• “Islands of Wonder” (8 p.m., PBS, TV-G, check local listings) debuts, with a look at Madagascar, considered the oldest island on Earth and one boasting a biodiversity rich enough to inspire endless study. And a CGI movie franchise (and spinoff Hulu series) to boot.

• With so many strange events occurring, it’s almost too easy to forget the extraordinary. “Notre-Dame: Our Lady of Paris” (9 p.m., ABC) recalls the 2019 conflagration that gutted the extraordinary 12th-century cathedral, a towering achievement of late-medieval engineering and civilization.

• As the Scarecrow taught us in “The Wizard of OZ,” some people think quite well without any brains at all. “NOVA” (9 p.m., PBS, TV-PG, check local listings) takes a scientific look at that notion with “Secret Mind of Slime.” Far from “Double Dare,” researchers pore over slime molds, extremely primitive organisms that appear to make “choices” without the benefit of a brain. Some believe slime behavior may hold the key to understanding “decision making” at its most basic.

While on the theme of decisions, “Hacking Your Mind” (10 p.m., PBS, TV-PG, check local listings) examines how corporations and marketers manipulate consumers into choices they only think are their own.

Other highlights

• ESPN offers baseball fans a double-header of sorts. The Phillies and Mets meet (7 p.m.), followed by the Diamondbacks and Angels (10 p.m.).

• Five acts proceed to the finals on “America’s Got Talent” (8 p.m., NBC, TV-PG).

• A busker wakes up to realize that he’s the only one in the world who remembers the Beatles in the 2019 musical fantasy “Yesterday” (8 p.m., HBO Signature).

• “Extreme Ice Machines” (9 p.m., Science, TV-PG) celebrates outrageous vehicles and tools designed for some of the coldest places on Earth.

Cult choice

TCM plays with themes of time travel with the 1949 adaptation of Mark Twain’s novel “A Connecticut Yankee in King Arthur’s Court” (8 p.m., TV-G), starring Bing Crosby. Katherine Turner and Nicolas Cage star in the 1986 return-to-the-Fifties fantasy “Peggy Sue Got Married” (10 p.m., TV-MA), directed by Francis Ford Coppola. Vintage time travel continues with “Repeat Performance” (midnight, TV-PG) and “Turn Back the Clock” (1:45 a.m., TV-G) from 1947 and 1933, respectively.

Series notes

Three courses for three finalists on the season-ender of “MasterChef” (8 p.m., Fox, r, TV-14) ... Prom dates on “The Goldbergs” (8 p.m., ABC, r, TV-PG) ... An unknown threat looms on “The 100” (8 p.m., CW, TV-14) ... Apartment hunting on “The Conners” (8:30 p.m., ABC, r, TV-PG) ... A lockdown isolates Jenny from her team on “Coroner” (9 p.m., CW, TV-14).

Late night

Drew Barrymore is on “The Late Show With Stephen Colbert” (11:35 p.m., CBS) ... Jimmy Fallon welcomes Sharon Stone, Shaquille O’Neal and Kylie Minogue on “The Tonight Show” (11:35 p.m., NBC) ... Cynthia Nixon, Michael Stipe and Sonny Emory visit “Late Night With Seth Meyers” (12:35 a.m., NBC).