When Earth and Mars are at their theoretically closest point of 54.6 million km, it would take a signal from Earth about 3 minutes to make the journey, and then another 3 minutes for the signals to get back to Earth.
Switchgrass is a hardy, deep-rooted, perennial rhizomatous grass that begins growth in late spring. It can grow up to 2.7 m high, but is typically shorter than big bluestem grass or indiangrass. The leaves are 30â90 cm long, with a prominent midrib.
Saltgrass is a perennial halophyte. The subspecies, Distichlis spicata spicata (L) Greene, is a California native that tolerates the alkali soil in the marsh plains and salt pans of coastal saltmarshes.altgrass is a salt excretor. Its roots take in seawater and saltwater is pumped out through special pores in the leaves. The sun evaporates the water and the salt crystals left behind become visible on the grass blades.