Just to assure accuracy for the people visiting. If you decide that you would like to do any maths related to this subject, here are the actual conversion values for U. Metric has been established in the UK for decades. School science has used SI and not Imperial for decades.
Trying to use both systems would waste time and risk dangerous errors. It becomes very complicated to use any standard derived unit such as Newton Force expressed by miles and pounds.
Further, 1 cubic decimeter equals 1 liter of water weighing 1kg which can also come in quite handy in everyday life. There is a good reason to stick to metric when discussing scientific matters. The distance to Mars varies because the Earth and Mars are both orbiting the sun, but not at the same speed or the same distance from the sun.
Sometimes we are on the opposite side of the sun from Mars, and the sun is therefore closer to us than Mars is. If the earth is on one side of the sun and mars is on the other side, then the distance from the earth to mars is greater than from the earth to the sun.
Seems pretty straight forward. All electromagnetic radiation travels at the speed of light. Gladson is wrong. Both earth and mars are in orbit around the sun. We make the trip in earth days. Mars requires earth days. Mars mean orbital radius to the sun is 1. Round trip radio time depends on where earth and mars are relative to the sun.
It varies, because Earth and Mars orbit the sun at different speeds. Sometimes they are on the same side of the sun and, at closest approach, light only takes about 3 minutes to travel between the two. Sometimes they are on opposite sides of the sun and it takes up to about 22 minutes. As to the other responses, the difference between speed of light and radio waves is negligible over these short distances. Depends on the positionsame of earth and Mars.
If we are on the same side of sun we are closer. If the planets are on opposite sides of sun. The sun is closer. The sun distance from Earth is relatively constant. Mars is not. Varges, we are not necessarily the same side of the sun at the same time — so the longest time is for when Earth and Mars are degrees opposite each other and both at aphelion, and the shortest would be when we are both the same side, with Mars at perihelion and Earth at aphelion.
Now you are making sense, but at that point how much longer will it take the suns light to reach mars? Well, you have to remember that both Earth and Mars are moving at different speeds while the rocket is en route. Nobody is suggesting that there need to be fundamental changes in physics here. I just want to establish some facts here for those who are confused about physics. That includes visible light, radio waves, and so forth. The speed of light in matter can vary, but in this case that is not important since all the space between mars, the earth, and the sun is vacuum.
The spacecraft was able to steer itself during entry into Mars' atmosphere with a series of S-curve manoeuvres similar to those used by astronauts piloting NASA space shuttles.
During the three minutes before touchdown, the craft slowed its descent with a parachute, then fired retrorockets mounted around the rim of its upper stage. In the final seconds, the upper stage acted as a sky crane, lowering the upright rover on a tether in order to land on its wheels. How are landing sites on Mars selected? In the s and s, detailed, accurate maps of Mars were not available, so the nature of the Martian surface was poorly understood. As a result, the Viking team decided to play safe by taking images of potential landing sites with the two orbiters before making a final selection of where to target their precious machines.
Since then, numerous orbiting spacecraft have mapped the Red Planet in great detail, so the emphasis is now as much on the scientific interest of the site as on the nature and relative safety of the terrain. Mars Pathfinder, for example, was targeted at an ancient river bed, while the Exploration Rovers and MSL headed for locations that were believed to have once supported surface water and potentially habitable environments.
However, a map of Martian landing sites shows that about half of the planet has so far been avoided. It is no coincidence that all successful landings on Mars have taken place in a region dominated by flat lowlands, rather than more rugged areas, such as the heavily cratered highlands found south of the equator.
Although the near-equatorial and northern plains are often marked by small impact craters, boulders of various sizes and dusty dunes, the chances of damage on arrival are quite small. Most of the landings have been at low latitudes, the sole exception to date being Phoenix, a stationary lander which survived for five months in the Martian Arctic before expiring as a result of the extreme cold and lack of sunlight.
Another factor that influences the choice of landing site is the thickness of the Martian atmosphere. On Earth, spacecraft can parachute or glide back through the dense blanket of air on completion of their orbital mission. The surface pressure is thickest over the deep canyons and thinnest above the giant volcanoes. Not surprisingly, mission planners have opted to target their craft over the lowland areas where the greater depth and thickness of atmosphere enables atmospheric friction and parachutes to slow the spacecraft's descent to the greatest extent.
ESA's ExoMars missions are no exception. Schiaparelli landed on Meridiani Planum , a relatively smooth, flat region close to the Martian equator and fairly near the current location of NASA's Opportunity rover. Three sites near the equator are currently being investigated for the ExoMars mission, which will deliver ESA's first planetary rover.
Almost all of the landers and roving vehicles delivered to Mars since Pathfinder in have been powered by solar panels. Schiaparelli was unusual by carrying only non-rechargeable batteries, so its active life, had it made it intact to the surface, would have been limited to only a few Martian days.
This is because its primary objective was to demonstrate entry, descent and landing technologies. The other exception is the nuclear-powered MSL, which is able to operate regardless of the amount of sunlight. The success and duration of the solar-powered surface missions depends upon the availability of sunlight to illuminate the solar cells.
Since Mars has similar seasons and periods of daylight to Earth, the landers' power budgets have to be managed carefully so that they can survive the shorter winter days — another reason for landing near the equator.
Mobile roving vehicles have the advantage of being able to park in a relatively sunny spot so that their batteries can be recharged. A build up of dust deposits on the solar panels may also reduce the vehicle's electrical output — although occasional gusts of wind may sweep away much of the brownish coating. Although ExoMars will arrive outside the main dust storm season, the mission team is aware that the solar-powered lander and rover may occasionally have to cease operations due to dust darkening the sky.
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OK Find out more about our cookie policy. Among the many thousands of images returned by Curiosity, some of the most spectacular were those of the Murray Buttes region of lower Mount Sharp.
Curiosity began a second two-year extended mission on Oct. At that point, the rover had returned more than , images to Earth. On Dec. Despite the problem with the drill, Curiosity was once again investigating active sand dunes the so-called Bagnold Dunes. As of Feb. In March , JPL controllers uploaded software for traction control that helped the rover adjust wheel speed depending on the rocks it is climbing.
The traction control algorithm uses real-time data to vary the wheel speed, thus reducing pressure from the rocks. The ridge was thought to be rich in an iron-oxide mineral known as hematite that can form under wet conditions. Two months later, the rover began making a steep ascent toward the ridge top. While it was still several months away from resuming full-scale drilling operations on the Martian surface, this and subsequent tests allowed ground controllers to test techniques, including using the motion of the robotic arm directly to advance the extended bit into the rock, thus working around the mechanical problem that had suspended drill work.
NASA has made significant attempts to involve the public in the Curiosity mission. On the third anniversary of landing on Mars, in August , the agency made available two online tools for public engagement. Mars Trek was a free web-based application that provides high-quality visualizations of the planet derived from 50 years of NASA exploration of Mars, while Experience Curiosity was a platform to allow viewers to experience in 3D, movement along the surface of Mars based on data from both Curiosity and MRO.
NASA also released a social media game, Mars Rover, for use on mobile devices where users can drive a rover through Martian terrain while earning points.
In April , scientists working with Curiosity announced the spacecraft had explored a region called "the clay-bearing unit" and tasted its first sample from this part of Mount Sharp. Curiosity drilled a piece of bedrock nicknamed Aberlady on April 6, , and delivered the sample to its internal mineralogy lab.
The rover's drill chewed easily through the rock, unlike some of the tougher targets it faced nearby on Vera Rubin Ridge. It was so soft, in fact, that the drill didn't need to use its percussive technique, which is helpful for snagging samples from hard rock. This was the mission's first sample obtained using only the rotation of the drill bit. Siddiqi, Asif A. What is Curiosity MSL? The rover began its first drive on Mars Aug. The rover is about as tall as a basketball player and uses a 7-foot 2-meter arm to place tools close to rocks for study.
A 3D model of the Curiosity Mars rover. The next full Moon is the Beaver Moon, and there will be a near-total lunar eclipse. Full Moon Guide: November - December This page showcases our resources for those interested in learning more about Mars. Mars Resources. NASA scientists are calling for a framework that provides context for findings related to the search for life.
Are We Alone in the Universe? Catch Mars mania as an exhibit visits more than a dozen towns across the U. Two microphones aboard the six-wheeled spacecraft add a new dimension to the way scientists and engineers explore the Red Planet. JPL's lucky peanuts are an unofficial tradition at big mission events. Full Moon Guide: October - November A new paper details how the hydrological cycle of the now-dry lake at Jezero Crater is more complicated than originally thought.
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