--- title: "Meaning & Key Takeaway of: The usual metric for whether a planet is…" description: "\"The usual metric for whether a planet is habitable or not is to ascertain whether liquid water could exist on its surface. Most worlds will either be t..." image: "https://sms4smile.com/quotes/i/d14/seth-shostak-2047_ascertain_the-usual-metric-for-whether-a-planet-is_3066973.jpg" --- # The usual metric for whether a planet is habitable or not… ![“The usual metric for whether a planet is habitable or not is to ascertain whether liquid water could exist on its surface. Most worlds will either be too cold, too hot or of a type (like Jupiter) that may have no solid surface and be swaddled in noxious gases.” quote by Seth Shostak](https://sms4smile.com/quotes/i/d14/seth-shostak-2047_ascertain_the-usual-metric-for-whether-a-planet-is_3066973.jpg) [Download](https://sms4smile.com/quotes/i/d14/seth-shostak-2047_ascertain_the-usual-metric-for-whether-a-planet-is_3066973.jpg) [Open image](https://sms4smile.com/quotes/i/d14/seth-shostak-2047_ascertain_the-usual-metric-for-whether-a-planet-is_3066973.jpg) > “The usual metric for whether a planet is habitable or not is to ascertain whether liquid water could exist on its surface. Most worlds will either be too cold, too hot or of a type (like Jupiter) that may have no solid surface and be swaddled in noxious gases.” [Seth Shostak](https://sms4smile.com/quotes/author/seth-shostak/) ## About This Quote This interpretation was drafted with AI assistance. It is one reading of the quote, not the author's own explanation. Habitability is judged by the presence of liquid water on a planet’s surface, which excludes many worlds that are too hot, too cold, or lack a solid surface. **In simple terms:** Habitability depends on surface liquid water. Key Takeaway Look for water when assessing habitability. Themes astronomy planetary science habitability Mood curious analytical Type scientific educational When to use this quote - exoplanet surveys - space telescope missions - educational outreach - science policy Key Concepts hydrology climate zones stellar radiation Questions to Reflect On - What other criteria could define habitability? - How do we study worlds with extreme conditions? A Different Perspective Planets without water can still be interesting for other reasons. ★ ★ ★ ★ ★ No ratings yet [Cold](https://sms4smile.com/quotes/about/cold/) [Gases](https://sms4smile.com/quotes/about/gases/) [Metric](https://sms4smile.com/quotes/about/metric/) [Planet](https://sms4smile.com/quotes/about/planet/) [Water](https://sms4smile.com/quotes/about/water/) ## Related quotes > [“We have built cities that scrape the sky, machines that think and a global network that allows people to yell at each other at…](https://sms4smile.com/quotes/natalie-kyriacou/we-have-built-cities-that-scrape-the-sky-machines-that-think-and-a/) [Natalie Kyriacou](https://sms4smile.com/quotes/author/natalie-kyriacou/) > [Data from orbiting telescopes like NASA's Kepler Mission hint that the tally of habitable planets in our galaxy is many billion. 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We…](https://sms4smile.com/quotes/george-muller/to-ascertain-the-lord-s-will-we-ought-to-use-scriptural-means-prayer/) [George Muller](https://sms4smile.com/quotes/author/george-muller/) > [My theory is that the way you cope with the depths will ascertain the heights that you reach - they are intimately connected -…](https://sms4smile.com/quotes/sebastian-horsley/my-theory-is-that-the-way-you-cope-with-the-depths-will-ascertain-the/) [Sebastian Horsley](https://sms4smile.com/quotes/author/sebastian-horsley/) > [“The true business of the philosopher, though not flattering to his vanity, is merely to ascertain, arrange and condense the facts.”](https://sms4smile.com/quotes/john-leslie/the-true-business-of-the-philosopher-though-not-flattering-to-his/) John Leslie > [How important it is to ascertain the will of God, before we undertake anything, because we are then not only blessed in our own…](https://sms4smile.com/quotes/george-muller/how-important-it-is-to-ascertain-the-will-of-god-before-we-undertake/) [George Muller](https://sms4smile.com/quotes/author/george-muller/) > [“Bodies that drown in deep water may never surface.”](https://sms4smile.com/quotes/steven-magee/bodies-that-drown-in-deep-water-may-never-surface/) [Steven Magee](https://sms4smile.com/quotes/author/steven-magee/) > [One volcano in Hawaii, one volcano in Indonesia, produces enough gases in the atmosphere, which include those natural elements that are in the Earth's…](https://sms4smile.com/quotes/jim-gibbons/one-volcano-in-hawaii-one-volcano-in-indonesia-produces-enough-gases/) [Jim Gibbons](https://sms4smile.com/quotes/author/jim-gibbons/) > [I am sure vegetarians must also account for a lot of gases. 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Prayer, the word of God, and His Spirit should be united together. We…](https://sms4smile.com/quotes/george-muller/to-ascertain-the-lord-s-will-we-ought-to-use-scriptural-means-prayer/) [George Muller](https://sms4smile.com/quotes/author/george-muller/) Browse all 5 Ascertain quotes ```json { "@context": "https://schema.org", "@graph": [ { "@type": "Quotation", "text": "The usual metric for whether a planet is habitable or not is to ascertain whether liquid water could exist on its surface. 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