A “blood moon” (total lunar eclipse with a red tint) happens roughly every 1–3 years somewhere on Earth, but any single location will usually see one only every few years.

What is a blood moon?

  • A blood moon is just a total lunar eclipse where Earth’s shadow makes the Moon look red or copper-colored.
  • The red color comes from sunlight being filtered and bent through Earth’s atmosphere, similar to a sunset.

How often does a blood moon occur?

  • Lunar eclipses of any kind happen about 2 times per year on average.
  • Only about 29% of those eclipses are total, so true “blood moons” occur about once every 1–3 years globally.
  • From one specific spot on Earth, you might see around 4–5 total lunar eclipses per decade, depending on your location and weather.

Special case: blood moon tetrads

Sometimes you hear about four blood moons in a row (a “tetrad”):

  • A tetrad is a series of four total lunar eclipses in about two years.
  • Tetrads are much rarer; on the scale of centuries, some eras have none, while others (like 1909–2156) have many.
  • Astronomers estimate they work out to roughly about once a decade or so in recent centuries, not a once-in-a-lifetime thing.

Recent and upcoming blood moons

  • Recent blood moons include 2018–2019 eclipses that were widely watched and photographed.
  • Upcoming total lunar eclipses (blood moons) are listed by astronomy sites, with notable ones in 2025 and later in the 2020s.

Quick forum-style takeaway

If you’re wondering “how often blood moon occur,” think of it this way:

  • Around 2 lunar eclipses a year, but only some are total.
  • A real red “blood moon” globally: every 1–3 years.
  • From your backyard: every few years on average, if skies are clear.

TL;DR: Blood moons aren’t super rare; one happens somewhere on Earth about every 1–3 years, but seeing one yourself depends on being on the right side of Earth with clear skies.

Information gathered from public forums or data available on the internet and portrayed here.