Bright, frosty polar caps, and clouds more than a vivid, rust-colored landscape reveal Mars as a dynamic seasonal planet in this NASA Hubble Space Telescope view in use on May 12, 2016, when Mars was 50 million miles from Earth. The Hubble picture reveals particulars as small as 20 to 30 miles across.
The huge, dark region at far right is Syrtis Major Planitia, one of the first features recognized on the surface of the planet by seventeenth-century observer. Christiaan Huygens used this trait to measure the turning round rate of Mars. (A Martian day is about 24 hours and 37 minutes.) Today we know that Syrtis Major is an very old, inactive shield volcano. Late-afternoon clouds enclose its summit in this view.
A huge oval feature to the south of Syrtis Major is the bright Hellas Planitia basin. About 1,100 miles across and near 5 miles deep, it was formed about 3.5 billion years ago by an asteroid impact.
The orange area in the inside of the image is Arabia Terra, a vast upland area in northern Mars that covers about 2,800 miles. The scenery is densely cratered and heavily eroded, representative that it could be in the midst of the oldest terrains on the planet. Dried river canyons (too small to be seen here) wind through the region and empty into the huge northern lowlands.
South of Arabia Terra, organization east to west along the equator, is the extended dark features known as Sinus Sabaeus (to the east) & Sinus Meridiani (to the west). These darker regions are enclosed by dark bedrock and fine-grained sand deposits earth down from ancient lava flows and other volcanic features. These sand grains are coarser and less reflective than the well dust that gives the brighter regions of Mars their ruddy appearance. Early Mars watchers opening mapped these regions.
An extensive blanket of clouds can be seen over the southern glacial cap. The icy northern polar cap has receded to a comparatively small size since it is now late summer in the northern hemisphere. Hubble photographed a wispy afternoon side cloud extending for at least 1,000 miles at mid-northern latitudes. Early morning clouds and haze make bigger along the western limb.
This hemisphere of Mars contains corridor sites for several NASA Mars surface robotic missions, including Viking 1 (1976), Mars Pathfinder (1997), and the still-operating chance Mars rover. The landing sites of the Spirit & Curiosity Mars rovers are on the other side of the planet.
This observation was made presently a few days before Mars opposition on May 22, when the sun and Mars will be on exact conflicting sides of Earth, and when Mars will be at a distance of 47.4 million miles from Earth. On May 30, Mars will be the closest it has been to Earth in 11 years, at a distance of 46.8 million miles. Mars is especially photogenic during opposition because it can be seen completely illuminated by the sun as viewed from Earth.
The biennial close approach between Mars and Earth are not all the same. Mars’ orbit around the sun is markedly elliptical; the close up approaches to Earth can variety from 35 million to 63 million miles.
They occur since about every two years Earth’s orbit catches up to Mars’ orbit, align the sun, Earth, and Mars in a as the crow flies line, so that Mars and the sun are on “opposing” sides of Earth. This phenomenon is a result of the dissimilarity in orbital period between Earth’s orbit and Mars’ orbit. While Earth take the familiar 365 days to travel once around the sun, Mars takes 687 Earth days to create its trip around our star. As a effect, Earth makes almost two full orbits in the time it takes Mars to create just one, resulting in the incidence of Martian oppositions about every 26 months.
The Hubble Space Telescope is a plan of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight inside in Greenbelt, Maryland, manages the telescope. The Space Telescope Science organization (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the friendship of Universities for Research in Astronomy in -Washington, D.C