{
  "id": 5215020,
  "title": "Giant mega-Earth is 23 times more massive than Earth",
  "url": "https://urgent.news/2026/09/03/giant-mega-earth-is-23-times-more-massive-than-earth",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-03T01:17:37.000Z",
  "source": {
    "name": "EarthSky",
    "slug": "earthsky",
    "url": "https://earthsky.org/space/giant-mega-earth-gj-523b-exoplanets/"
  },
  "original_language": "en",
  "account": "Scientists have confirmed the existence of an unusual planet called GJ 523b, which belongs to a rare group of worlds known as mega-Earths. This planet is 23.5 times more massive than Earth, despite being only about 2.5 times wider. This makes GJ 523b exceedingly dense, a characteristic that scientists are struggling to understand. Typically, planets this massive would have thick atmospheres of hydrogen and helium, but GJ 523b does not seem to possess such an atmosphere. It is believed to be only 170 million years old, much younger than our own solar system, which is approximately 4.54 billion years old. The planet orbits an orange dwarf star. The unexpected density and lack of atmosphere have left astronomers puzzled about the planet's formation.",
  "summary": "Astronomers have discovered a new giant mega-Earth exoplanet that is a whopping 23 times as massive as Earth, and 2.5 times the size. The post Giant mega-Earth is 23 times more massive than Earth first appeared on EarthSky .",
  "key_points": [
    "GJ 523b is a mega-Earth 23.5 times more massive than Earth",
    "Planet has no atmosphere despite its massive size",
    "GJ 523b is 170 million years old, much younger than our solar system"
  ],
  "editors_take": "The discovery of GJ 523b's unusual density and lack of atmosphere challenges scientists' understanding of planetary formation, particularly for massive worlds like this rare mega-Earth.",
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}