Exoplanet Transit Depth

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Earth & Space (astronomy, orbital mechanics, meteorology, geology, geodesy, oceanography)

Tranche

tranche-4

Evidence ID

t4-029

Ledger rows

1

No ledger note is attached.

Review findings

The forward formula is correct under the stated uniform-disk approximation, but the instrument claims reverse radius inference without specifying its inverse formula or depth-unit interface. The honest label should also disclose the opaque-planet, non-grazing, no-third-light assumptions; uniform stellar brightness alone is not sufficient to characterize all limitations.

Formula and scope findings

• The forward formula ΔF/F = (Rp/Rs)^2 is standard for a uniform stellar disk when the planet fully occults a region of the stellar disk and there is no contaminating or additional light.
• The claimed reverse calculation is underspecified: the required inverse formula Rp = Rs × sqrt(ΔF/F) is not included.
• The specification does not state whether the supplied depth is a fraction, percentage, or ppm, nor the required conversion between these representations.
• For grazing transits, the simple area-ratio formula is not generally valid because only part of the planet may overlap the stellar disk.

Unit assumptions

• Rp and Rs must be expressed in the same length units before forming Rp/Rs; kilometers, meters, or consistent radius units are acceptable.
• A fractional depth d converts to percent as 100d and to ppm as 1,000,000d.
• A depth supplied in ppm must be converted as d = depth_ppm / 1,000,000 before applying the inverse formula.
• For the inverse calculation, Rp = Rs × sqrt(d), with d dimensionless.
• If nominal IAU radii are used, the specific nominal constants and their units must be exposed consistently; this validation uses 695700 km for the nominal solar radius where applicable.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

A zero star radius produces an undefined division, and an oversized planet produces a raw depth above 100% unless the instrument validates or caps the result. Negative-radius input also reveals an unguarded sign-convention hazard.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "planet_radius_km": 69570,
    "star_radius_km": 695700
  },
  "expected_outputs": {
    "depth_fraction": 0.01,
    "depth_percent": 1,
    "depth_ppm": 10000
  },
  "working": "1. Rp/Rs = 69570 / 695700 = 0.1. 2. ΔF/F = (0.1)^2 = 0.01. 3. Percent depth = 0.01 × 100 = 1%. 4. Ppm depth = 0.01 × 1000000 = 10000 ppm."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche4/tranche4-results.json
• BOUNDARY_HAZARD_CATALOG.json