Habitable Zone

{
  "asOf": "2026-10-11T08:48:41.986Z",
  "conservativeZoneAu": {
    "inner": 0.9931,
    "outer": 1.705
  },
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "inFittedTemperatureRange": true,
  "luminositySolar": 1,
  "luminositySource": "given",
  "method": "Kopparapu et al. 2013 (ApJ 765, 131): moist greenhouse to maximum greenhouse limits (conservative); recent Venus to early Mars limits (optimistic); distance = sqrt(L / S_eff(Teff))",
  "notChecked": [
    "planet properties: mass, atmosphere, albedo and the greenhouse effect set what the zone really is for a given planet",
    "stellar activity, flares, tidal locking and the star's changing brightness over time",
    "…2 more"
  ],
  "optimisticZoneAu": {
    "inner": 0.7505,
    "outer": 1.774
  },
  "orbitAu": 1,
  "orbitSource": "given",
  "position": "INSIDE_CONSERVATIVE_ZONE",
  "reasons": [
    "Star temperature is inside the model's fitted range (2600 to 7200 K)."
  ],
  "source": "computed locally",
  "summary": "For L = 1 solar and Teff 5780 K, the conservative habitable zone is 0.993 to 1.71 au and the optimistic zone 0.751 to 1.77 au. An orbit at 1 au: inside conservative hz.",
  "teffK": 5780,
  "verdict": "INSIDE_CONSERVATIVE_HZ"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://exoplanets-nasa.x402tookit.com/habitable-zone?luminositySolar=1&orbitAu=1&teffK=5780'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://exoplanets-nasa.x402tookit.com/habitable-zone?luminositySolar=1&orbitAu=1&teffK=5780' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fexoplanets-nasa.x402tookit.com%2Fhabitable-zone
const res = await pay("https://exoplanets-nasa.x402tookit.com/habitable-zone?luminositySolar=1&orbitAu=1&teffK=5780");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://exoplanets-nasa.x402tookit.com/habitable-zone?luminositySolar=1&orbitAu=1&teffK=5780")
    print(res.status_code, res.text)