How Many Years?
Constellation Representation
When "GH" Sounds Like F
Science
What is This, A Crossover Episode?
200

Centennial

What is 100?

200

This mythic strongman gets the fifth-largest constellation

Who is Hercules?

200

Proverbially, you can do this "out of the other side of your mouth"

What is laugh?

200

A ruler is divided into inches & a thermometer is divided into these

What are degrees?

200

Zoinks! Hunters Sam and Dean find themselves in a classic cartoon and help out this famous mystery-solving team and their Great Dane.

What are "Supernatural" and "Scooby-Doo"?

400

Triennial

What is 3?

400

Pictor is this, a painter's stand

What is an easel?

400

A person difficult to know or convince is a this nut to crack

What is tough?

400

Increased levels of this gas in the atmosphere add to the greenhouse effect, warming the earth

What is carbon dioxide?

400

The pressure's on to stop a stink bomb at Springfield Elementary!  Special Truancy Agents Jack Bauer and Chloe O'Brian are the only ones who can save the city!

What are "The Simpsons" and "24"?

600

Septennial

What is 7?

600

Sagittarius is the archer; Sagitta is this

What is the arrow?

600

This long, narrow receptacle holds food for animals

What is a trough?

600

This light display may be "Australis" or "Borealis"

What is the aurora?

600

In 2009 this ambitious crossover involved three Investigative teams; one from Las Vegas and two other major cities.

What are "SCI," "CSI: Miami," and "CSI New York"?

800

Quadricentennial

What is 400?

800

This Zodiac constellation resembles twins

What is Gemini?

800

It means having a coarse surface; you can find it bordering a golf fairway

What is rough?

800

In 1953 Crick & Watson came up with the double helix model for this nucleic acid's molecule

What is DNA?

800

Agents Fox Mulder and Dana Scully investigate a mysterious incident in Los Angeles, enlisting a TV crew from a real life crime-focused reality show.

What are "The X-Files" and "Cops"?

1000

Novennial

What is 9?

1000

Virgo is a maiden; Monoceros is this mythical beast that represents maidenhood

What is a unicorn?

1000

An adequate quantity

What is enough?

1000

Making up about 80% of the air, it has to be "fixed" before you can use it

What is nitrogen?

1000

Cmdr. Rabb and Lt. Col. MacKenzie required the investigative services of Special Agent Gibbs and his team in this 2-part episode.  This would also serve as the backdoor pilot for the latter team.

What are JAG and NCIS?