The Moon was likely created from debris expelled when a Mars-sized object violently impacted the Earth about 4.5 billion years ago. Just after gravitationally condensing, as imagined above, the glowing-hot surface of the Moon cooled and cracked. Rocks large and small continued to impact the surface, including a particularly large impact that created Aitken Basin about 4.3 billion years ago. A Heavy Bombardment period then continued for hundreds of millions of years, creating large basins all over the lunar surface. Over the next few billion years lava flowed into Earth-side basins, eventually cooling into the dark maria we see today. As always, relentless impacts continued, forming the craters we see today, slowly diminishing over the past billion years. Today the cooled Moon we know and love is as dark as coal and always keeps the same face toward Earth. Exactly how the Moon formed initially, and why lunar maria are only on the Earth side, remain active topics of research.
This day and night are equal over
all planet Earth
1999 2000 2001 2002
2003 2004 2005 2006
2007 2008 2009 2010
2011 2012 2013 2014
2015 2016 2017 2018
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Публикации с ключевыми словами:
Moon - Луна - столкновения - эволюция солнечной системы
Публикации со словами: Moon - Луна - столкновения - эволюция солнечной системы
Все публикации на ту же тему >>
Мнения читателей