ScaleTrip

Travel through scale.

How wide is the Sun?

ScaleTrip uses about 1,392,000 kilometres for the Sun's diameter. Diameter measures across the Sun through its centre and is twice the listed radius.

Sun diameterDiameter · 1,392,000 km

The distance across the Sun through its centre.

About 3.6 × Earth–Moon distance
Earth–Moon distance · 384,400 km
Explored distance1,392,000 km

Bars: actual length ratio. Artwork: browsing size.

Explore the scale
1,392,000 km

Time at constant speed

Time = distance ÷ speed · Assumes no acceleration or stops.

A constant-speed calculation for comparing distance scales. Ground-vehicle times through planetary interiors or space are mathematical comparisons; real space travel requires orbital dynamics and changing velocity.

Objects move along logarithmic spacing, while size is compressed from the real ratio to remain legible.

Artwork and diagram notes

Object, landmark, planet and cosmic-scale artwork is original AI-generated imagery made for ScaleTrip. Maps use public-domain Natural Earth boundaries. Illustrations use logarithmic visual compression to keep objects recognizable; the numerical measurements retain their real values.

Earth becomes a tiny dot in a 1 m Earth–Sun model

A Solar System picture often enlarges the planets so you can see them. To understand the empty space, keep the same reduction for both the planets and their gaps.

Earth becomes a tiny dot in a 1 m Earth–Sun model — explanatory illustration, not a measurement image
An illustration for recognizing the subject. Read the adjacent diagram for the stated scale.
Earth becomes a tiny dot in a 1 m Earth–Sun modelA common-scale model: 1 m between Earth and Sun, Sun about 9.3 mm across, Earth about 0.085 mm across. The Earth is shown at its calculated size, not enlarged.1 m≈ 9.3 mm≈ 0.085 mm
A common-scale model: 1 m between Earth and Sun, Sun about 9.3 mm across, Earth about 0.085 mm across. The Earth is shown at its calculated size, not enlarged.

Work it out, one step at a time

  1. Compare Earth’s diameter with the gap

    12,742 ÷ 149,597,870.7 ≈ 0.0000852

    The diameter and distance must use the same unit: kilometres.

  2. Shrink the gap to 1,000 mm

    0.0000852 × 1,000 mm ≈ 0.085 mm

    A readable planet icon and a common-scale planet serve different purposes. Check the caption.

Words made simple

Astronomical unit (au)
An exactly defined length close to the average Earth–Sun separation.
Think about it: If the model gap is 10 m, does model Earth stay 0.085 mm wide?

No. Every model length grows tenfold, so Earth becomes about 0.85 mm wide.

Where the numbers come from: NASA JPL · NIST SP 330. The illustration and worked model are made for this lesson; assumptions are stated above.

Build a scale modelChoose two references and change the model size.

Build a scale model of any two lengths

Choose from all 71 Macro and 54 Micro references, or enter your own length. Set B’s model length and see A change on the same fixed metre ruler. The bars represent the stated lengths, including their different measurement definitions.

Measurements and model scale
Length ratio A / B
2×
Model length B
10 cm
Calculated model length A
20 cm
AB01 m2 m
Fixed scale: 1 m uses 250 drawing units. Moving the model-size slider changes the bar lengths, while the real measurements stay fixed.
AB
Full ratio view: the longer length fills the width. Sub-pixel lengths retain their computed width; read the numerical ratio for very different scales.

A · Sun diameter

1.392e+9 m

Comparison derived from the nominal solar radius: 2 × 696,000 km = 1,392,000 km.

Calculated from a sourced value

The IAU nominal radius is an exact conversion constant, not the true instantaneous solar radius. This comparison rounds it first; the diameter doubles that rounded radius.

Definition and evidence reviewOriginal source

B · Sun radius

6.960e+8 m

Comparison derived from the nominal solar radius: 695,700 km → 696,000 km.

Calculated from a sourced value

The IAU nominal radius is an exact conversion constant, not the true instantaneous solar radius. This comparison rounds it first; the diameter doubles that rounded radius.

Definition and evidence reviewOriginal source

model A = (A / B) × model B

This calculator uses the existing journey comparison inputs. Review-pending or conceptual entries remain illustrative inputs here; the public reviewed dataset keeps their numeric values withheld. Radius, height, diameter and experimental bound keep their individual definitions.

Calculation method · Link to this comparison lab

km1,392,000
m1,392,000,000
mi864,948.6996

How many Earth diameters span the Sun?

Using the displayed 1,392,000 km solar diameter and the 12,742 km mean Earth diameter gives about 109.2. This is a one-dimensional width ratio; a packing comparison would require a separate volume calculation.

A rounded value for a diffuse body

NASA lists a volumetric mean solar radius of 695,700 km. Twice that is 1,391,400 km; ScaleTrip retains a coarser rounded comparison value. The Sun is plasma, so its visible surface is a radiating plasma layer. Displayed travel times are mathematical comparisons across its diameter.

Closest ScaleTrip references

Page distance: 1,392,000 km

  1. Sun diameterReference measurement: Diameter · 1,392,000 km
    Ratio (page distance ÷ reference): ≈ 1×

    The distance across the Sun through its centre.

  2. Sun radiusReference measurement: Radius · 696,000 km
    Ratio (page distance ÷ reference): ≈ 2×

    The average distance from the Sun's centre to its visible surface.

  3. Earth–Moon distanceReference measurement: Distance · 384,400 km
    Ratio (page distance ÷ reference): ≈ 3.62×

    The average centre-to-centre distance from Earth to the Moon.

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Sources for these values

  • NASA NSSDC — Sun Fact Sheet — rounded solar diameter from the 695,700 km volumetric mean radius · calculation verified from source value 2026-10-08