The Bridge V Learning Edition 1 ; our solar system | Page 11

Uranus
U ra nu s is the se ve n th pl ane t from the Sun. It i s n o t visi ble to the nak e d e ye
a nd i t be came the fi rs t pl ane t di sc o vered wi th th e u se o f a teles co pe . U ranu s i s
ti pp ed o n i t’ s s ide wi th an axi al ti l t of 98 de g re es . It is some time s d es c rib ed as
“rol lin g a ro un d th e s un on i t’s si de .” U ra nus ha s two se ts of ve ry th i n d ark
c ol ou re d rin gs . T he rin g p a rtic le s a re small ra ngi ng f rom du s t s ize d pa rti cl es to
sm all b oul de rs . Th e y we re p ro ba bl y fo rmed wh en on e o r mo re of U ra nu s’s
moo ns we re b rok en up in imp ac t . Its su rf ac e l o ok s ve ry smoo th a nd ba rel y
s ho ws a n y s tru c tu re . It h a s 27 k n o wn mo on s .
U ra nu s ha s a h yd ro ge n u pp er la ye r wh ich h as H eli um mi xed in . B elo w tha t i s
a n i c y ma n tle whic h su rroun ds a ro ck an d ic e c o re . The up pe r a tmo sph e re i s
mad e of wa te r, ammon ia and me tha ne i ce c rys tal s th a t gi ve the p lan e t i ts p ale
b lue co lou r.
U ra nu s is the col de s t p la ne t i n th e s ola r sys tem wi th minimum temp e ra tu re s of
-2 24 C .