Time-travel pod
From Memory Alpha, the free Star Trek reference.
Time travel pods were craft used by historians from the distant future, from as early as the 26th century, to as late as the 31st century, to study various points in time. (TNG: "A Matter of Time"; ENT: "Future Tense")
The Federation also employed larger timeships within this timeframe. (VOY: "Future's End", "Relativity")
