Tag

Light Year

All articles tagged with #light year

Voyager 1 Keeps Coasting Toward a Light-Day Milestone
space19 days ago

Voyager 1 Keeps Coasting Toward a Light-Day Milestone

Voyager 1, launched in 1977, remains the fastest and most distant human-made object, cruising at about 17 km/s with no engine. It has crossed the heliopause into interstellar space and sits roughly 25 billion kilometers from the Sun (about 170 AU). NASA expects it to reach about one light-day from Earth by November 2026, a distance at which light takes a day to reach Voyager and come back. Power is fading—from an initial ~470 watts to well under half—so engineers are shutting instruments offline; only two remain as the team plans further power-saving steps. When power runs out, Voyager 1 will go quiet but continue coasting for thousands of years, not aimed at any particular star (in ~40,000 years it will pass about 1.6 light-years from Gliese 445).

Andromeda's Light Lets Us See a 2.5-Million-Year Moment
space1 month ago

Andromeda's Light Lets Us See a 2.5-Million-Year Moment

Seeing Andromeda with the naked eye means viewing light that began its journey about 2.5 million years ago—the era when early Homo in Africa were first making stone tools; Andromeda (M31) is the Local Group’s largest galaxy and the farthest naked-eye object at 2.5 million light-years, approaching the Milky Way at ~110 km/s with a predicted merger in ~4.5 billion years; the visible glow is the bright core, while deep images reveal hundreds of millions of stars, illustrating astronomy as time travel into the past.

"Bill Nye Breaks Down the Universe's Immense Scale with Light-Years"
science3 years ago

"Bill Nye Breaks Down the Universe's Immense Scale with Light-Years"

Bill Nye explains that a light-year is the distance light travels in one year, which is 5.88 trillion miles. The vastness of space led astronomers to create manageable units of measurement. A light-year can be broken down into smaller units like a light day, hour, minute, etc. Understanding the meaning of a light-year is important for space exploration and answering big questions about the universe.