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.
Quackgrass (Elytrigia repens) Quackgrass, a perennial grass, is a B-rated noxious weed in California. It is found throughout California, except deserts, up to 5900 feet (about 1800 m), but is primarily found in northern and coastal regions. Quackgrass inhabits moist meadows and disturbed sites.