by Mike Selinker, Foggy Brume, Ian Tullis, and Meta Group B, cache locations by Stephen Peters, Zack Butler, Greg Lohman, and Graham Wright
Answer: EPSILON ERIDANI

The "galaxocaching" website looks suspiciously like geocaching.com, except it instructs teams to use their "Galactic Positioning Systems" to find caches on various stars. There are seven caches in Ursa Major (the Harvoid Constellation), but oddly, they all lead to the same place.

Like on most geocaches, each cache page contains a clue in rot13 (A=N, B=O, etc.). Here, the caches' clues can be strung together to create a bit of doggerel:

When Algernon suffered

His horrible crash

He left you a clue

In each galaxocache

To order the clues as

The stars you are spannin'

You might Google "cache"

And "Annie Jump Cannon"

Googling the delightfully science-fictiony astronomer "Annie Jump Cannon" and "cache" will bring up a real geocache called "Oh Be A Fine Girl, Kiss Me!" located not far from Harvard. The cache discusses in detail Ms. Jump Cannon's work on a star-type ordering system known as the “Oh Be A Fine Girl, Kiss Me” (OBAFGKM) method—a.k.a. the "Harvard scheme."

Each galaxocache has the following locator number, star correspondence, cache title, mnemonic word, cache location, and answer, presented in the order of the star mnemonic. Algernon has also left a codeword to open the virtual version of the cache puzzle.

Cache	Star	Title	Mnemonic	Location	Answer
GXCPHCD	Phecda	Out Huntin'	OH	JFK School of Government	LEPER COLONY
GXCDUBH	Dubhe	Brodie Encounter	BE	between Aldrich and Burden	DRAMATIS PERSONAE
GXCALTH	Alioth	Aliotherapy	A	Harvard St. and Mass Ave	PSALM BOOK
GXCALKD	Alkaid	Friends In Noble England	FINE	Gund Graduate School of Design	PICCADILLY CIRCUS
GXCMIZR	Mizar	Growth Involves Reconstructing Legos	GIRL	Carpenter Center for the Visual Arts	TRAUMA CENTER
GXCMRAK	Mirak	Keep It Stylin', Stupid	KISS	Harvard Business School	INDETERMINATE EQUATION
GXCMGRZ	Megrez	Megrez Expedition	ME	Malkin Athletic Center	TUCSON, ARIZONA

At the site of the geocache, players may sign the logbook. Algernon has already done so. In his note, he has added seven key words. These seven words are the entry passwords for each of the cache puzzles. Each is one or more pictures that solve to these entries:

GXCPHCD (Phecda): LEPER COLONY

GXCDUBH (Dubhe): DRAMATIS PERSONAE

GXCALTH (Alioth): PSALM BOOK

GXCALKD (Alkaid): PICCADILLY CIRCUS

GXCMIZR (Mizar): TRAUMA CENTER

GXCMRAK (Mirak): INDETERMINATE EQUATION

GXCMGRZ (Megrez): TUCSON, ARIZONA

These solutions require the game's box cover to decode. The cover...

...can be paired with this constellation map, obtained on the galaxocaching site.

...this shows the matchup.

Overlay the starmap on the cover, and certain constellations will line up with different letters. By the standard constellation abbreviations, answers can be matched to two constellations each (Pictor and Circinus for PICCADILLY CIRCUS). Going to those constellations’ caching pages and looking at the cache names for each constellation will spell out a message in OBAFGKM order.

Lepus (Lep) and Columba (Col): E-E

Draco (Dra) and Perseus (Per): P-R

Pisces Australus (PsA) and Bootes (Boo): S-I

Pictor (Pic) and Circinus (Cir): I-D

Triangulum Australe (TrA) and Centaurus (Cen): L-A

Indus (Ind) and Equuleus (Equ): O-N

Tucana (Tuc) and Aries (Ari): N-I

Reading the left-half letters, then the right, spells Algernon's location, EPSILON ERIDANI.