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Mars

Mars is the fourth planet from the Sun and the seventh largest in the Solar System. A cold, dusty desert world with a thin atmosphere (mostly CO₂), the planet features extinct volcanoes, deep canyons, polar ice caps, and seasons. Mars has two small moons (Phobos and Deimos), a day just over 24 hours long, and a year lasting about 687 Earth days. It is a prime focus of robotic exploration and studies about past water and habitability.

Source: science.nasa.gov

APODs including "Mars"

Galaxy and Planets Beyond Bristlecone Pines

19/06/2016

Galaxy and Planets Beyond Bristlecone Pines
Image Credit: Brad Goldpaint (Goldpaint Photography) / NASA APOD

What's older than these ancient trees? Nobody you know -- but almost everything in the background of this picture. The trees are impressively old -- each part of the Ancient Bristlecone Pine Forest located in eastern California, USA. There, many of the oldest trees known are located, some dating as far back as about 5,000 years. Seemingly attached to tree branches, but actually much farther in the distance, are the bright orbs of Saturn (left) and Mars. These planets formed along with the Earth and the early Solar System much earlier -- about 4.5 billion years ago. Swooping down diagonally from the upper left is the oldest structure pictured: the central band of our Milky Way Galaxy -- dating back around 9 billion years. The featured image was built from several exposures all taken from the same location -- but only a few weeks ago.