How many planets are in our solar system? And how many planets are in our nearest solar system? And how many moons does earth have in the year 2025?
Executive summary
Our Solar System is officially recorded as having eight planets — Mercury through Neptune — after Pluto’s reclassification in 2006; NASA and multiple outlets repeat “eight planets” in 2025 reporting [1] [2]. The nearest stellar system, Alpha Centauri (the closest star system) has candidate and tentative planets reported in 2025 but no single, incontrovertible count; recent Webb and archive reports describe possible planets (e.g., a candidate around Alpha Centauri A and new confirmations in nearby systems) rather than a fixed tally [3] [4]. Earth in 2025 has one true natural moon (the Moon); astronomers also track temporary “quasi‑moons” such as objects that share Earth’s orbit but orbit the Sun — these are not counted as additional true moons [5] [6].
1. How many planets are in our Solar System — the settled headline
Professional bodies and major science outlets report eight major planets in our Solar System: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. NASA’s educational materials and contemporary guides consistently use “eight planets” as the operative count in 2025 [1] [2]. Popular reporting about 2025 sky events (planet parades and alignments) also treats those eight as the roster observers look for in the sky [7] [8].
2. Why some people still say “nine” — the Pluto backstory and hypotheticals
Pluto’s 2006 reclassification to “dwarf planet” left a cultural residue: older references and many readers still think of nine planets. Scientific sources note that dwarf planets (including Pluto) are counted separately; NASA’s pages explain the IAU definition that led to Pluto’s demotion and now list eight planets plus recognized dwarf planets [1] [2]. Separately, researchers continue to search for distant, hypothetical objects (often called “Planet Nine” or other variants) beyond Neptune; such proposals are active research topics but are not confirmed planets in the official eight [9].
3. Nearest solar system — what “nearest” means and what we actually know
“Nearest solar system” usually refers to the nearest star system with planets. The closest star to us, Proxima Centauri, and the Alpha Centauri triple system are the obvious candidates; catalogs and literature list candidate planets around these stars, and 2025 exoplanet archives report newly confirmed planets in nearby systems [10] [4]. Notably, NASA/JPL reported Webb team evidence of a possible giant planet around Alpha Centauri A in 2025 — an encouraging but not yet definitive finding — and exoplanet archives list many newly confirmed worlds across nearby systems [3] [4]. Available sources do not give a single, universally agreed numeric count of “how many planets” in the nearest star system because some detections remain candidate-level, debated, or under follow-up [10] [3].
4. Earth’s moons in 2025 — one official moon; more nuance in “quasi‑moons”
Earth has one true natural satellite — the Moon — and the standard educational resources and NASA pages state that plainly [5] [1]. In 2025 reporting scientists also document temporary or co-orbital objects called quasi‑moons or quasi‑satellites: small asteroids that share Earth’s orbital period and can appear to “hang around” Earth for years without being gravitationally bound as moons. News and analysis stress these are not additional true moons; they orbit the Sun, not Earth [6] [11]. As of 2025, sources discuss at least several known quasi‑moons historically; specific objects such as 2025 PN7 appear in later 2025 reporting as a long-lived quasi‑satellite, but that post‑August item is outside the strict March–mid‑2025 snapshot and must be treated separately [12] [6].
5. Numbers that matter (what to cite if you need figures)
- Official count of planets in our Solar System: eight [1] [2].
- Moons in the Solar System (broader context): NASA noted 891 confirmed moons as of March 25, 2025, with 421 orbiting planets and the rest around dwarf planets, asteroids and TNOs — useful context for satellite counting, though Earth’s count remains one [13].
- Nearest-system planets: various candidate and confirmed planets have been reported around the closest stars (Proxima Centauri, Alpha Centauri and others), and exoplanet archives list new confirmations in 2025 — but no single authoritative “nearest system has X planets” figure is universally reported in the sources provided [10] [4].
6. Takeaway and how to read future headlines
Science communication tends to simplify: “eight planets” and “Earth has one moon” are accurate summaries supported by NASA and mainstream outlets [1] [5]. Headlines about extras — a “second moon” or a new planet in our backyard — often refer to quasi‑moons, candidate exoplanets, or hypothetical distant planets; those stories require follow‑up because detection, confirmation, and naming take years and can be overturned or revised [6] [3]. When you see dramatic claims about new nearby planets or extra moons, check whether sources call them “candidate,” “quasi‑satellite,” or “confirmed” — the difference determines whether they change the canonical counts cited above [3] [6].
Limitations: this briefing cites contemporary 2025 sources provided here; available sources do not present a single authoritative numeric total for “planets in Alpha Centauri” and do not treat quasi‑moons as true additional moons for Earth [10] [6].