HOME PLATE (MARS)

:''For the baseball term, see Home plate. For the album by Bonnie Raitt, see Home Plate.''
'Home Plate' is an informal nickname used by NASA scientists to refer to a geological feature on Mars currently under study by the Spirit rover, as of April 2006. It is a rocky outcrop that appears to show layered features. Its name comes from the similarity of its shape with a baseball home plate.
Home Plate is a rocky outcrop about the size of a large house, but with a flat-topped shape; from above, it looks vaguely pentagonal. It is located within the huge Gusev crater, just south of Husband Hill.
The feature is interesting to scientists because of its layered appearance. ''Spirit's'' twin, ''Opportunity'', currently studying sites on the opposite side of the planet, has discovered numerous layered rocks, but Home Plate is the first example to be found at Spirit's site. It bears a striking similarity to Burns Cliff, a feature studied by Opportunity at Endurance crater.
Spirit arrived at Home Plate on sol 744 (February 7, 2006) and has completed a scientific investigation with her robotic arm before moving to Low Ridge Haven to due to power concerns. She returned on sol 1126 to resume those studies. ^[1]



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Contents

Origins

References

External links

See Also

Origins

Scientists now believe that Home Plate is an explosive volcanic deposit. It is surrounded by deposits of basalt, which exploded on contact with water. The presence of brine is further supported by the high concentration of chloride ions in the surrounding rocks. The presence of bomb sags seems to confirm this hypothesis.^[2]
A patch of 90% pure silicon dioxide was unearthed by Spirit in the vicinity of Home Plate. This provides what is reckoned to be the strongest evidence yet that liquid water existed in this area for substantial periods of time. ^[3]

References

1. Spirit Homes in on Mitcheltree Ridge, Opportunity Crosses Valley Without Peril A.J.S. Rayl
2. Pyroclastic Activity at Home Plate in Gusev Crater, Mars, Squyres, et al, , , Science,
3. Mars Rover Spirit Unearths Surprise Evidence of Wetter Past

External links

★ Nasa's Mars Exploration Program

★ Current position of the Mars rovers - Home Plate is visible, with Spirit's journey around it.

★ www.marsgeo.com The Geology of Home Plate

★ The Planetary Society Weblog: Home, Sweet Home for Spirit

★ Official Mars Rovers site

See Also

★ List of rocks on Mars