{"id":953,"date":"2004-11-19T08:31:00","date_gmt":"2004-11-19T07:31:00","guid":{"rendered":"https:\/\/kids.esa.int\/telltale_signs\/"},"modified":"2026-10-08T00:34:10","modified_gmt":"2026-10-07T22:34:10","slug":"telltale_signs","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/nl\/telltale_signs\/","title":{"rendered":"Tekenen van leven"},"content":{"rendered":"
\n

De Aarde is de enige ons bekende plek waar leven mogelijk is. Wat maakt onze planeet nu zo bijzonder? Wel, onder andere omdat er vloeibaar water is. Het leven op Aarde lijkt te zijn begonnen in plassen of zee\u00ebn van water. Zonder water zou er geen leven mogelijk zijn op onze planeet.<\/p>\n<\/div>\n

De aarde is de enige plek in ons zonnestelsel met grote oceanen aan het oppervlak. Dit komt doordat zij zich in de \u2018Goldilocks\u2019-zone bevindt.<\/p>\n

Venus staat zo dichtbij de Zon dat het er te heet is. Mars staat weer te ver weg en is daardoor te koud. Maar de Aarde staat op precies de juiste afstand en is niet te warm en niet te koud.<\/p>\n

Zouden er \u2018Aardes\u2019 kunnen zijn die rond andere sterren draaien? Hoe zouden wij die kunnen herkennen? Het eerste wat wij moeten doen, is meten hoe warm of koud een planeet is. Er zou ook bewijs moeten zijn dat er water in overvloed aanwezig is.<\/p>\n

Tenslotte zullen we op zoek moeten gaan naar gassen als zuurstof en methaan. Dat zijn gassen die worden geproduceerd door levende wezens.<\/p>\n

Toekomstige missies zullen in duizenden ster-planeetstelsels naar deze \u2018biomarkers\u2019 zoeken. Hoewel zij zuurstof niet rechtstreeks zullen detecteren, zullen zij ozon, een vorm van zuurstof, wel \u2018waarnemen\u2019. Zij zullen ook kooldioxide, water en, in bepaalde gevallen, methaan waarnemen.<\/p>","protected":false},"excerpt":{"rendered":"

Earth is the only place we know that supports life. What makes it so special? One key factor is the presence of liquid water. Life on Earth seems to have […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"esa_banner_image":"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2002\/01\/planet_earth_as_seen_by_the_apollo_17_astronauts2\/17863973-3-eng-GB\/Planet_Earth_as_seen_by_the_Apollo_17_astronauts.jpg","esa_banner_description":"Planet Earth as seen by the Apollo 17 astronauts","esa_banner_credit":"NASA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2002\/01\/Planet_Earth_as_seen_by_the_Apollo_17_astronauts2","esa_external_url":"","esa_external_new_window":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":true},"categories":[14,10,13],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-953","post","type-post","status-publish","format-standard","hentry","category-are-we-alone","category-learn","category-life-in-space","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/posts\/953","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/comments?post=953"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/posts\/953\/revisions"}],"predecessor-version":[{"id":2096,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/posts\/953\/revisions\/2096"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/media?parent=953"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/categories?post=953"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/tags?post=953"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/panel?post=953"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/language?post=953"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/age?post=953"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/duration?post=953"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/resource_type?post=953"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/audience?post=953"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/nl\/wp-json\/wp\/v2\/wf_post_folders?post=953"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}