OBSERVED
114,105
searched stars
Exoearth Evidence Observatory · by Biswajit Jana
Finding Earth 2.0
in distant worlds
What did we detect? What could our surveys detect? What underlying population is consistent with those observations? Which measurement should we make next? Every point behind this text is a real system with a measured distance, drawn at its catalogue sky position.
0
confirmed planets
across 4,764 systems
0
source records
13 archive tables
0
spectral measurements
104 planets with spectra
0
in the conservative HZ
279 optimistic
Of 6,354 confirmed planets, only 15 are both inside the conservative habitable zone and small enough to be plausibly rocky — and only 1 of those has a mass that was actually measured rather than predicted from its radius.
The search is not limited by how many planets we know about. It is limited by how few we have measured well.
6,327 systems rendered · 27 excluded for having no measured distance · radial axis log-compressed
Exoearth Evidence Observatory
The research, opened into eleven rooms
The story now moves from what humanity detected, through the instruments and models that shape those detections, to the experiment that would reduce uncertainty next. Every room keeps observations, inference, scenarios and forecasts visibly separate.
Read what I learned while building it →The question
Five things that get conflated, kept apart
Headlines collapse “Earth-sized”, “habitable-zone”, “potentially habitable” and “could host life” into one claim. They are different claims, supported by different evidence, and this project reports them separately at every stage.
- Earth similarity
- Bulk radius, density, escape velocity and equilibrium temperature resemble Earth's.
- Habitable-zone position
- Incident flux is compatible with surface liquid water under a stated climate model.
- Rocky plausibility
- Radius sits below the regime where planets are predominantly volatile-rich.
- Atmospheric observability
- Whether an atmosphere could be characterised with current instruments.
- Evidence for life
- Not established for any planet. No metric here estimates it.
New population chapter
The catalogue is only what Kepler could see
I followed 89 DR25 candidates backwards through reliability, transit geometry, pipeline recovery and vetting. The result is a conditional population posterior with its uncertainty and claim boundary kept visible.
See observed become intrinsic →MODEL-INFERRED
78.3
effective stars
MODEL-INFERRED
0.692
planets per star
Computed ranking
Leading candidates
Produced by the pipeline, not selected by hand. The intervals are 16th–84th percentiles from 4,000 Monte Carlo draws per planet.
| # | Planet | Earth-2.0 index | Earth Similarity Index | Habitable zone | Mass | Radius | Distance |
|---|---|---|---|---|---|---|---|
| 1 | Proxima Cen bM5.5 V | 0.876 | HZ 100% | M sin i | 1.02 R⊕ | 1.3 pc / 4.2 ly | |
| 2 | GJ 1061 dM5.5 V | 0.875 | HZ 100% | measured | 1.16 R⊕ | 3.7 pc / 12.0 ly | |
| 3 | GJ 1002 bM5.5 V | 0.849 | HZ 100% | M sin i | 1.03 R⊕ | 4.8 pc / 15.8 ly | |
| 4 | Wolf 1069 bM5.0 V | 0.839 | HZ 100% | M sin i | 1.08 R⊕ | 9.6 pc / 31.3 ly | |
| 5 | Teegarden's Star cM7.0 V | 0.823 | HZ 100% | M sin i | 1.02 R⊕ | 3.8 pc / 12.5 ly | |
| 6 | Kepler-1649 c | 0.774 | HZ 96% | inferred | 1.06 R⊕ | 92.2 pc / 300.7 ly | |
| 7 | GJ 1002 cM5.5 V | 0.771 | HZ 96% | M sin i | 1.10 R⊕ | 4.8 pc / 15.8 ly | |
| 8 | Kepler-1229 b | 0.716 | HZ 100% | inferred | 1.40 R⊕ | 265.5 pc / 865.9 ly |
Why the ranking looks like this
47%
of catalogue masses were never measured
2,975 planets carry a mass predicted from their radius by a mass–radius relation. Density and escape velocity computed from such a mass re-encode the radius rather than adding information, so the Earth Similarity Index would appear to combine four independent properties while being driven by one.
0.92
Venus scores 0.92 on the Earth Similarity Index
Venus’s high albedo makes its equilibrium temperature cooler than Earth’s, and equilibrium temperature is the only temperature exoplanet catalogues provide. An ESI built on data that exists for real exoplanets cannot separate an Earth from a Venus. Venus runs through the whole pipeline as a control so this is visible rather than asserted.
~1 ppm
is an Earth twin’s atmospheric signal
For a real nitrogen–oxygen atmosphere around a Sun-like star, the transmission signal is about one part per million — against a current best precision of tens of ppm. Finding an Earth twin and characterising its atmosphere are separated by a generation of instruments.
Every number on this site traces back to a source.
89,131 measurement links · 1,814 publications · 66,228 with ADS bibcodes · 11,736 values calculated by the archive rather than measured
Data source trail →Inspect the observations
104 planets
Spectral Lab
Published transmission and emission spectra with expected molecular band positions — marked as band positions, never as detections.
Open →
4 of 4 validated
Transit Lab
Light curves retrieved from MAST, detrended, folded and fitted, with every fit checked against the published depth before it is reported.
Open →
Proxima recovered
RV Lab
Radial velocities from DACE with a mandatory stellar-activity cross-check, because a rotating spotted star imitates a planet.
Open →
Data coverage
What looks measured, and what is actually quantified
The pale bar is how many planets have a value at all. The solid bar is how many have that value with a published uncertainty. The gap between them is the part of the catalogue that looks measured but cannot be propagated — and it is large.
What this analysis cannot establish →- Stellar mass100% / 96%
- System distance100% / 98%
- Planet mass100% / 48%
- Planet radius99% / 69%
- Bulk density98% / 23%
- Stellar effective temperature95% / 90%
- Stellar luminosity95% / 61%
- Stellar radius95% / 91%
- Orbital period95% / 87%
- Semi-major axis93% / 62%