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Solar and Lunar Eclipses: Interactive 3D Simulator & Diagram

Grades 6–8 · MS-ESS1-1

Line up the Sun, Moon and Earth to turn day into night, turn the Moon red and find real eclipses.

Solar and Lunar Eclipses

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What is the difference between a solar and a lunar eclipse?

A solar eclipse happens when the Moon lines up between the Sun and Earth, so its shadow falls on Earth (at new moon). A lunar eclipse happens when Earth lines up between the Sun and the Moon, so Earth’s shadow falls on the Moon (at full moon). The Moon’s orbit is tilted about 5°, so most months the shadows miss.

In this lab you can

  • Line up the Sun, Moon and Earth in 3D and make a total, partial or ring of fire solar eclipse, then see it from the ground with the corona and the diamond ring.
  • Move the Moon into Earth’s shadow and watch it turn copper-red; change the dust in Earth’s air.
  • Play a whole year with a flat orbit and with the real 5.1° tilt to see why eclipses come only in eclipse seasons.
  • Find the real eclipses of 2026–2045 from NASA’s list and see what your city sees, such as about 6 min 20 s of totality in Luxor on 2 Aug 2027.

Activities in this lab: Solar or lunar: can you tell the difference? · Why isn’t there an eclipse every month? · Can you build a model of both eclipses? · Does Earth’s shadow cause the Moon’s phases? · Who can see a solar eclipse, and who sees a lunar one? · How close must the Moon be for a total eclipse? · Can you predict the eclipses of 2029?

Modes in this lab: Solar eclipse · Lunar eclipse · Why not every month? · Total or ring of fire? · Real eclipses · Sizes

On this page: Solar vs Lunar Eclipse: What’s the Difference?What Is a Solar Eclipse?What Is a Lunar Eclipse?What Is a Blood Moon?How Often Do Eclipses Happen?What Is an Annular (Ring of Fire) Eclipse?What Are the Umbra and Penumbra?When Is the Next Total Solar Eclipse?How Big Is the Moon Compared to Earth?Is It Safe to Look at a Solar or Lunar Eclipse?What Are the Types of Eclipses?Go Deeper: Saros Cycles, Eclipse Seasons and the FutureHow long is the Moon’s shadow?Myths and factsFAQSources

Solar vs Lunar Eclipse: What’s the Difference?

The difference is which body is in the middle. In a solar eclipse the Moon passes between the Sun and Earth and blocks the Sun; in a lunar eclipse Earth passes between the Sun and the Moon and its shadow darkens the Moon. A solar eclipse can only happen at new moon and a lunar eclipse only at full moon, and every calendar year has 2 to 5 solar eclipses somewhere on Earth (NASA Five Millennium Catalog of Solar Eclipses).

Solar and lunar eclipses diagram: in a solar eclipse the Moon is between the Sun and Earth and its umbra and penumbra fall on Earth; in a lunar eclipse Earth is between the Sun and the Moon and the Moon moves into Earth’s umbra
Solar eclipse (top): Sun – Moon – Earth, at new moon. Lunar eclipse (bottom): Sun – Earth – Moon, at full moon. Drawn by SciSim from the lab’s own geometry; sizes and distances not to scale.
Solar and lunar eclipses compared (NASA eclipse list and fact sheets)
Solar eclipseLunar eclipse
What lines upSun – Moon – Earth (the Moon in the middle)Sun – Earth – Moon (Earth in the middle)
Moon phaseNew moonFull moon
Whose shadow falls on whatThe Moon’s shadow on EarthEarth’s shadow on the Moon
Who can see itTotality only in a narrow path, usually about 100–250 km wide; a partial eclipse over a wide area around itEveryone on the side of Earth where the Moon is up
Longest total phaseA few minutes: 6 min 23 s on 2 Aug 2027, never more than about 7½ minutesOver 1½ hours: 1 h 42 min on 26 Jun 2029
How often2 to 5 a year somewhere on Earth2 to 4 a year in 2026–2045, counting faint penumbral ones
Safe to look atOnly with ISO 12312-2 eclipse glasses or a pinhole projector; bare eyes only during totalityYes, with bare eyes, binoculars or a telescope
What it looks likeA bite out of the Sun, a ring of fire, or a black disc with the pearly coronaThe Moon darkens and often turns copper-red

Try it in the lab: Solar or lunar: can you tell the difference? ↑ Try it in the lab: Can you build a model of both eclipses? ↑

What Is a Solar Eclipse?

A solar eclipse happens when the Moon passes between the Sun and Earth and its shadow falls on Earth. Inside the Moon’s dark shadow, the umbra, the whole Sun is hidden: the sky turns dark, the brightest stars and planets come out and the Sun’s pearly corona appears around the black Moon. The umbra is small when it reaches Earth: at most about 270 km across. The path it sweeps over the ground is usually about 100–250 km wide, and wider where the Sun is low in the sky. On 2 August 2027 the path is about 260 km wide near Luxor, Egypt. Luxor gets about 6 minutes 20 seconds of totality; the longest, 6 min 23 s, is a little to the east (NASA eclipse list 2021–2030). Around the path, the lighter penumbra gives a partial eclipse: Riyadh sees 76 % of the Sun covered, Tunis 97 % and Dhaka only 3 %.

Totality never lasts long: at most about 7½ minutes (NASA), because the shadow races across Earth at more than 1,700 km/h.

Try it in the lab: Solar eclipse ↑ Try it in the lab: Who can see a solar eclipse, and who sees a lunar one? ↑

What Is a Lunar Eclipse?

A lunar eclipse happens when Earth passes between the Sun and the Moon, so Earth’s shadow falls on the full Moon. Earth’s dark shadow at the Moon’s distance is about 9,350 km across, more than 2½ times as wide as the Moon, which is why a lunar eclipse lasts hours: the Moon can stay fully inside it for 1 h 42 min, as on 26 June 2029 (NASA eclipse list 2021–2030). Everyone on the night side of Earth can see it, and it is safe to watch without special eyewear (NASA Scientific Visualization Studio).

Earth’s shadow does not cause the Moon’s phases: it points straight away from the Sun and touches the Moon only at full moon during an eclipse season. During a partial lunar eclipse the edge of the shadow is always curved, one of the oldest pieces of evidence that Earth is round. Compare the phases in the Moon Phases lab.

Try it in the lab: Lunar eclipse ↑ Try it in the lab: Does Earth’s shadow cause the Moon’s phases? ↑

What Is a Blood Moon?

A blood moon is the copper-red Moon of a total lunar eclipse. Even inside Earth’s dark shadow the Moon is not black, because the only sunlight left reaching it has passed through the ring of Earth’s air around the edge of our planet (NASA Scientific Visualization Studio). The air scatters most of the blue light away and bends the red light into the shadow, as at sunset. More dust or clouds in the air (after a big volcanic eruption, for example) make the Moon darker and redder; astronomers rate this on the Danjon scale from L = 0 (almost invisible) to L = 4 (bright copper-orange) (NASA). NASA’s list has 17 total lunar eclipses in 2026–2045, so a blood moon comes about once a year on average, though some years have none.

Try it in the lab: Lunar eclipse, Total (blood moon) ↑

How Often Do Eclipses Happen?

Every calendar year has at least two and at most five solar eclipses somewhere on Earth (NASA Five Millennium Catalog), and NASA’s list for 2026–2045 has two to four lunar eclipses a year, counting the faint penumbral ones. They come in eclipse seasons, about twice a year: in 2029 there are four partial solar eclipses and two total lunar eclipses, in January, June–July and December (NASA eclipse list 2021–2030). Any one place sees a total solar eclipse only rarely; NASA’s list for 2026–2045 has 15 total, 16 annular, 1 hybrid and 12 partial solar eclipses.

Why don’t eclipses happen every month?

The Moon’s orbit is tilted 5.145° to Earth’s orbit (NASA Moon fact sheet), so at most new and full moons the Moon passes up to about 34,500 km above or below the Sun–Earth line and both shadows miss. The Moon crosses Earth’s orbital plane at only two points, the nodes. An eclipse needs a new or full moon close to a node, and the Sun lines up with the node line only twice in each 346.6-day eclipse year: these are the eclipse seasons, about 32–35 days long and about 173 days apart. Because the eclipse year is about 19 days shorter than a calendar year, the seasons come about 19 days earlier each year. Eclipse seasons have nothing to do with summer and winter, which come from Earth’s tilt: see the Seasons lab.

Try it in the lab: Why not every month? ↑ Try it in the lab: Why isn’t there an eclipse every month? ↑ Try it in the lab: Can you predict the eclipses of 2029? ↑

What Is an Annular (Ring of Fire) Eclipse?

An annular eclipse is a solar eclipse in which the Moon is too far from Earth to cover the whole Sun, so a bright ring of sunlight, the “ring of fire”, stays around the Moon. The Moon’s distance changes during each orbit, from about 363,300 km at mean perigee to 405,500 km at mean apogee (NASA Moon fact sheet). Seen from Earth it looks from about 29.5 to 32.9 arcminutes wide (an arcminute is 1/60 of a degree), while the Sun looks from 31.5 to 32.5 (NASA Sun fact sheet). At its average distance of 384,400 km the Moon looks 31.6 arcminutes wide even from right under it, a little smaller than the Sun’s 32.0 at its average distance: such an eclipse is a ring of fire. The next one is on 6 February 2027.

Even the thinnest ring of fire is still part of the Sun’s bright face, so an annular eclipse is never safe to look at without eclipse glasses.

Try it in the lab: Total or ring of fire? ↑ Try it in the lab: How close must the Moon be for a total eclipse? ↑

What Are the Umbra and Penumbra?

The umbra is the dark inner part of a shadow, where the light source is completely hidden; the penumbra is the lighter outer part, where only some of it is hidden. A wide light source such as the Sun always makes both: sunlight comes from every point of the Sun’s disc, so behind the Moon the rays form a dark cone that narrows to a tip, inside a lighter cone that widens. Standing in the Moon’s umbra you see a total eclipse, in the penumbra a partial one; beyond the umbra’s tip, in the antumbra, you see a ring of fire. At average distances the Moon’s umbra is about 373,600 km long, just short of Earth’s surface, while Earth’s much longer umbra reaches about 1.4 million km into space (calculated from the sizes and distances in the NASA fact sheets (NASA Sun fact sheet)).

Try it in the lab: Solar eclipse, Partial ↑

When Is the Next Total Solar Eclipse?

The next total solar eclipse is on 2 August 2027; its path of totality crosses Morocco, Spain, Algeria, Libya, Egypt, Saudi Arabia, Yemen and Somalia (NASA eclipse list). The longest totality of 2026–2045 is the 2 August 2027 eclipse, with 6 min 23 s on the centre line in Egypt. The next total solar eclipse seen from the United States is on 30 March 2033 (Utqiagvik, Alaska), and the lower 48 states see one on 23 August 2044. The lab’s Real eclipses mode shows every eclipse of 2026–2045 and what your city sees.

The next total solar eclipses (NASA). The longest totality is on the centre line; most places in the path get less.
DateTypeLongest totalityPath of totality crosses
2 Aug 2027Total6 min 23 sMorocco, Spain, Algeria, Libya, Egypt, Saudi Arabia, Yemen, Somalia
22 Jul 2028Total5 min 10 sAustralia, N.Z.
25 Nov 2030Total3 min 44 sBotswana, S. Africa, Australia
14 Nov 2031Hybrid (total and annular)1 min 08 sPacific, Panama
30 Mar 2033Total2 min 37 se Russia, Alaska
20 Mar 2034Total4 min 09 sNigeria, Cameroon, Chad, Sudan, Egypt, Saudi Arabia, Iran, Afghanistan, Pakistan, India, China
2 Sep 2035Total2 min 54 sChina, Korea, Japan, Pacific
13 Jul 2037Total3 min 58 sAustralia, New Zealand

When is the next lunar eclipse?

The next lunar eclipse is on 20 February 2027 (penumbral), and the next total lunar eclipse, a blood moon, is on 31 December 2028 (NASA lunar eclipse list).

The next lunar eclipses (NASA). Seen from wherever the Moon is up at the time.
DateTypeTotal phaseSeen from
20 Feb 2027Penumbral–Americas, Europe, Africa, Asia
18 Jul 2027Penumbral–e Africa, Asia, Australia, Pacific
17 Aug 2027Penumbral–Pacific, Americas
12 Jan 2028Partial– (partial 56 min)Americas, Europe, Africa
6 Jul 2028Partial– (partial 2 h 21 min)Europe, Africa, Asia, Australia
31 Dec 2028Total (blood moon)1 h 11 minEurope, Africa, Asia, Australia, Pacific

Try it in the lab: Real eclipses ↑

How Big Is the Moon Compared to Earth?

The Moon is about a quarter as wide as Earth: 3,474.8 km across against Earth’s 12,742 km, so 3.7 Moons would fit across Earth (NASA Moon fact sheet). It is also far away: about 30 Earths would fit in the 384,400 km between them. The Sun is about 400 times wider than the Moon but also about 390 times farther away, which is why the two look almost the same size in our sky, and why total eclipses are possible at all. Compare many more sizes in the Scale of the Universe lab.

Earth and the Moon (NASA fact sheets)
EarthMoon
Diameter12,742 km3,474.8 km (Earth is 3.7 times wider)
Gravity at the surface1 g (9.8 m/s²)0.165 g (1.62 m/s²)
Distance between them384,400 km on average, about 30 Earths lined up (363,300–405,500 km at mean perigee and apogee)
AirYes: it bends sunlight into Earth’s shadow and turns the eclipsed Moon redNo: the sky on the Moon is black even in daytime

Try it in the lab: Sizes ↑

Is It Safe to Look at a Solar or Lunar Eclipse?

A lunar eclipse is completely safe to watch with bare eyes, binoculars or a telescope. A solar eclipse is not: before and after totality, and during a partial or annular eclipse, look at the Sun only through eclipse glasses or handheld solar viewers that meet the ISO 12312-2 standard, or watch the projected image from a pinhole projector with the Sun behind you (NASA).

“regular sunglasses, no matter how dark, are not safe for viewing the Sun”

Only during totality, when the Moon completely covers the Sun’s bright face, is it safe to look with bare eyes; put the glasses back on as soon as the first bright bead of sunlight returns. Children should watch with an adult. Never look at the Sun through a camera, telescope or binoculars without a proper solar filter on the front.

What Are the Types of Eclipses?

There are four types of solar eclipse (total, annular, partial and hybrid) and three types of lunar eclipse (total, partial and penumbral) (NASA solar eclipse types)(NASA lunar eclipse list). The type depends on which part of the shadow falls where: the dark umbra, the lighter penumbra or, for a ring of fire, the antumbra beyond the umbra’s tip.

The seven types of eclipse, with the next one of each after this page was built (NASA)
TypeWhat happensNext one
Total solarThe Moon covers the whole Sun; day turns into night in a narrow path2 Aug 2027
Annular solar (ring of fire)The Moon is too far away to cover the whole Sun; a bright ring stays6 Feb 2027
Partial solarOnly the Moon’s lighter shadow touches Earth; the Sun looks bitten14 Jan 2029
Hybrid solarTotal along part of the path, a ring of fire along the rest14 Nov 2031
Total lunar (blood moon)The whole Moon is inside Earth’s dark shadow and turns copper-red31 Dec 2028
Partial lunarPart of the Moon enters Earth’s dark shadow12 Jan 2028
Penumbral lunarThe Moon passes only through Earth’s lighter shadow and dims a little20 Feb 2027

Go Deeper: Saros Cycles, Eclipse Seasons and the Future

Saros cycles, the eclipse year, the Danjon scale and why total eclipses will end (high school)

Saros: after 6,585.32 days (18 years 11 days 8 hours) the Sun, Moon and node line return to almost the same arrangement, so a very similar eclipse happens again, about a third of the way around Earth to the west (NASA). The long total eclipses of 2 August 2027 and 12 August 2045 are one saros apart.

Eclipse year: the Sun returns to the same node every 346.62 days because the node line turns westward once every 18.6 years. Two eclipse seasons fit in each eclipse year, 173.3 days apart.

Ecliptic limits: with average distances, a solar eclipse happens somewhere on Earth if a new moon falls within about 16.7° of a node; an umbral lunar eclipse needs a full moon within about 10.7° (calculated in this lab from the NASA fact sheet values). An eclipse season is longer than a month, so every season has at least one solar eclipse.

The far future: laser ranging shows the Moon moving away from Earth by about 3.8 cm a year (NASA). In the very far future it will look too small to cover the Sun, and only rings of fire will remain.

How this lab calculates: every eclipse type, % covered and shadow width comes from the true sizes and distances; the 3D picture only squeezes them so they fit on the screen. Real dates come from NASA’s eclipse list (Fred Espenak, NASA GSFC); times and city views from Astronomy Engine (Astronomy Engine), checked against NASA for all 89 eclipses of 2026–2045.

Key terms

Umbra
The dark inner part of a shadow, where the light source is completely hidden.
Penumbra
The lighter outer part of a shadow, where the light source is only partly hidden.
Antumbra
The region beyond the tip of the umbra, where the Moon looks smaller than the Sun and a ring of fire is seen.
Corona
The Sun’s thin outer atmosphere, seen as a pearly glow during totality.
Totality
The time during which the Sun or the Moon is completely inside the dark shadow.
Annular eclipse
A solar eclipse in which a bright ring of the Sun stays around the Moon.
Node
One of the two points where the Moon’s tilted orbit crosses the plane of Earth’s orbit.
Eclipse season
The few weeks, about twice a year, when the Sun is close enough to a node for eclipses to happen.
New moon
The phase when the Moon is between the Sun and Earth and its dark side faces us.
Full moon
The phase when the Moon is on the far side of Earth from the Sun and fully lit.

How long is the Moon’s shadow?

Whether you see a total eclipse or a ring of fire depends on whether the tip of the Moon’s dark shadow reaches you. Its length follows from similar triangles, with the sizes from the NASA fact sheets (NASA Sun and Moon fact sheets):

  1. Draw it: the dark shadow is a cone. Its edges touch the Sun’s edge and the Moon’s edge and meet at the tip, a distance L behind the Moon.
  2. Similar triangles: L ÷ Moon radius = (Sun–Moon distance + L) ÷ Sun radius, so L = Sun–Moon distance × Moon radius ÷ (Sun radius − Moon radius).
  3. Put in the numbers: at new moon the Moon is 149.6 million − 384,400 km from the Sun; L = 149,215,600 × 1,737.4 ÷ (695,700 − 1,737.4) ≈ 373,600 km.
  4. Compare: a person right under the Moon is 384,400 − 6,371 = 378,029 km from it, farther than 373,600 km: the tip falls short and the person sees a ring of fire.
  5. The limit: the shadow reaches the person only if the Moon’s centre is closer than about 373,600 + 6,371 ≈ 380,000 km from Earth’s centre.
  6. Check it with sizes: from right under the Moon at 384,400 km, the Moon looks 31.6′ wide and the Sun 32.0′, so the Moon is slightly too small: a ring of fire, as the lab shows.

Myths and facts

Myth: There is an eclipse every month.

Fact: The Moon’s orbit is tilted 5.1°, so the shadows usually miss; eclipses come only in short eclipse seasons, about twice a year.

Myth: The Moon’s phases are caused by Earth’s shadow.

Fact: Phases come from how much of the Moon’s sunlit half we see. Earth’s shadow falls on the Moon only during a lunar eclipse, at full moon.

Myth: Everyone on the day side of Earth sees a total solar eclipse.

Fact: Only people in the narrow path of the Moon’s dark shadow, usually about 100–250 km wide, see totality; others see a partial eclipse or nothing.

Myth: During a total lunar eclipse the Moon turns black and disappears.

Fact: It usually glows copper-red: sunlight bent through Earth’s air still reaches it.

Myth: Sunglasses are fine for watching a nearly total solar eclipse.

Fact: Even a thin crescent of the Sun can hurt your eyes. Use ISO 12312-2 eclipse glasses or a pinhole projector (NASA).

Your next lab

Seasons →Tilt Earth and see why we have summer and winter (the rest of MS-ESS1-1).Moon Phases →See every phase from space and from your city.Solar System →Fly from the Sun to Neptune at true distances.

Frequently asked questions

When was the last total solar eclipse?

The last total solar eclipse was on 12 August 2026; its path of totality crossed the Arctic, Greenland, Iceland and Spain (NASA). The next one is on 2 August 2027.

How long does a solar eclipse last?

The partial phases take about two to three hours from the first bite to the last. Totality lasts only a few minutes: on 2 August 2027 up to 6 min 23 s, the longest of 2026–2045, and never more than about 7½ minutes (NASA).

How long does a lunar eclipse last?

Several hours. In 2026–2045 the Moon spends up to 3 h 51 min partly or fully inside Earth’s dark shadow (7 Aug 2036) and is completely inside it for up to 1 h 42 min (26 Jun 2029), according to NASA’s list.

What phase is the Moon in during an eclipse?

A solar eclipse always happens at new moon, when the Moon is between the Sun and Earth. A lunar eclipse always happens at full moon, when the Moon is on the far side of Earth from the Sun.

What is the path of totality?

It is the narrow strip of Earth’s surface swept by the Moon’s dark shadow, where a total solar eclipse is seen. The shadow itself is at most about 270 km across, and the path is usually about 100–250 km wide; it is wider where the Sun is low (about 300 km on 12 August 2026). On 2 August 2027 it is about 260 km wide near Luxor.

What is a penumbral lunar eclipse?

The Moon passes only through Earth’s lighter outer shadow, the penumbra. It dims a little, often too little to notice. The next one is on 20 February 2027.

What is a hybrid solar eclipse?

A solar eclipse that is total along part of its path and a ring of fire (annular) along the rest, because the tip of the Moon’s dark shadow only just reaches Earth. The next one is on 14 November 2031 (NASA).

How often is there a blood moon?

A blood moon is a total lunar eclipse. NASA’s list has 17 of them in 2026–2045, so about one a year on average, but they come in runs and gaps (four in a row in 2032–33, none in 2030–31): 2029 has two, and the next one after this page was built is on 31 December 2028.

Why does the Moon look the same size as the Sun?

The Sun is about 400 times wider than the Moon but also about 390 times farther away, so both look about half a degree wide. The Moon’s distance changes, so sometimes it looks slightly bigger (total eclipse) and sometimes slightly smaller (ring of fire).

What is the Saros cycle?

A period of 6,585.32 days (18 years 11 days 8 hours) after which a very similar eclipse happens again, shifted about a third of the way around Earth. The total eclipses of 2 August 2027 and 12 August 2045 are one saros apart.

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Sources

  1. NASA GSFC: Solar eclipses 2021–2030 (Eclipse Predictions by Fred Espenak, NASA's GSFC)
  2. NASA GSFC: Solar eclipses 2031–2040
  3. NASA GSFC: Solar eclipses 2041–2050
  4. NASA GSFC: Lunar eclipses 2021–2030
  5. NASA GSFC: Lunar eclipses 2031–2040
  6. NASA GSFC: Lunar eclipses 2041–2050
  7. NASA GSFC: Five Millennium Catalog of Solar Eclipses
  8. NASA GSFC: Periodicity of solar eclipses (saros)
  9. NASA GSFC: Danjon scale of lunar eclipse brightness
  10. NASA GSFC: Measuring the Moon’s distance (Apollo laser ranging)
  11. NASA Moon fact sheet
  12. NASA Sun fact sheet
  13. NASA Earth fact sheet
  14. NASA Science: Eclipse viewing safety
  15. NASA Science: Types of solar eclipses
  16. NASA Scientific Visualization Studio: Total lunar eclipse, March 2025
  17. NASA Sun-Earth Day: Eclipse facts
  18. OpenStax Astronomy 2e, 4.7 Eclipses of the Sun and Moon (CC BY 4.0)
  19. Moon surface map in the 3D view: Solar System Scope (CC BY 4.0), based on NASA data
  20. Earth map in the 3D view: NASA Blue Marble (public domain)
  21. Astronomy Engine 2.1.19 (MIT licence), Don Cross

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Cite this page

SciSim. (2026, November 8). Solar and lunar eclipses: interactive 3d simulator & diagram. https://scisim.org/sims/earth-space/solar_and_lunar_eclipses