story identification - Old sci-fi show about some kids that travel to a distant part of space and are trapped by the boss in a spear of influence

I'm not sure if it was a series or a mini series but some kids get lost on a space ship and end up finding a long lost earth. The ship might be called "Merlin" and it has an AI. They end up being noticed by the bad guys and they activate something called the "spear of influence". It detects any ship that passes the barrier of a huge area of space so they are trapped. I remember one part of the plot was regarding the ship running out of water so they had to get more from an asteroid or a comet.
If anyone remembers the name please let me know

Answer

While looking at other questions, I came upon this one, which was answered with Hypernauts. While improving the answer, I found some matching points to yours.

The premise of the series was that three cadets from the Academy of Galactic Exploration become lost in a Hyper Bubble (hyperspace) mid-jump and must band together with an alien named Kulai in order to survive in an unfamiliar part of the galaxy. Kulai (unbeknownst to the cadets) is a Chalim priestess from a planet called Pyria, a planet that was strip-mined by a warlike race called the Triiad, led by the Pyran traitor, Paiyin. The sole purpose of the Triiad is to wipe out intelligent races, and in the process acquire raw materials from their destroyed planets to continually create new war machines using automated self-replicating factory ships called "Makers."

The Hypernauts, as they name themselves, cannot match the Triiad's firepower with their own so they must rely on stealth, wits and (occasionally) their modified 'mech suits' in order to escape the Triiad. They are based in an ancient abandoned exploration ship called the Star Ranger which is hidden in an asteroid field, the Star Ranger's obsolete AI is named Horten. For long range missions they use a four-person shuttle called the Flapjack which like the Star Ranger is Hyper Bubble capable but has a much shorter range.

The Triiad have englobed the central region of the Milky Way Galaxy in a sensor net that can identify the destination point of any hyperspace jump passing out of it, so returning home would lead the Triiad directly to Earth. The Hypernauts must keep the location of Earth a secret and somehow try to warn Earth of the Triiad's existence.

In Episode 3, "Icebound":

The Star Ranger begins to run low on water, so the Hypernauts land on a nearby ice moon where they discover an ancient space craft, and giant heat seeking worms.

Earth isn't lost, per se, but they are initially lost, and they can't warp back home, because it will tell the Triiads where earth is.

Here is the intro: