What's the farthest distance human or unmanned spacecrafts are able to travel?
We could theoretically get humans to one of the Lagrangian points of earth and back, if we wanted to. More than 3 months flight-time without resupply is currently not technologically tested. But possible. We would not need only slightly more time for flying past Venus, but about 2.5 years for a typical Mars mission, since the launch windows to Mars or back are more rare. Unmanned spacecraft could get VERY far, but practically they are frozen after electrical power runs out, which happens in about 30 years for long-distance probes. Voyager 2 is currently 90 AU away from the sun, or 90 times the distance Earth-Sun. It will reach about 100 AU until electrical power runs out, but will fly on as dead junk, leave eventually the solar system and fly into the galaxy, slowly traveling away in a orbit around the center similar to the sun - it would then need about 225 million years for one loop around the galaxy, but never leave it. For leaving the galaxy, we would need much faster probes as we have today. Short explanation of the math that is ahead: The escape velocity is always square root of two multiplied with the local circular orbit velocity - regardless where you actually are, how fast orbital velocity is and which object you orbit. About 41% higher than orbital velocity. If you leave an orbit at exactly escape velocity, you will have zero velocity in excess when you leave the gravity well of a planet, sun or galaxy. For calculating the speed needed for having a special excess velocity vex, you use the formula Vesc = sqrt(2*vo^2 + vex^2). This includes the effect of being faster means less velocity being lost to the gravity of the central body of your orbit. A very simple formula, like most simple stuff in spaceflight. The sun moves at 225 km/s around the galaxy, for leaving the galaxy you need 41% more speed relative to the galaxy, 93 km/s relative to the sun. This means you have to leave Earths gravity well at 101 km/s and leave a parking orbit around Earth at 101.5 km/s. For comparison: The fastest unmanned probe we have so far, New Horizons, left Earth at slow 19.6 km/s. It is still a long way to go in spaceflight.
Why are there no spaceships?
On the oceans we have lot's of ships. These ships are designed for the ocean. They don't leap up onto land or dive under the ocean. Good airplanes and good boats never come from car-airplane or car-boat combinations. A permanent spaceship could be reused in space. We have re-used the ISS for over 10 years now. We aren't sending up new stations for each mission. So, why do we have to send a new spaceship up for a manned Moon or Mars mission each time? Wouldn't it be better to use a Nautilus-X approach (NASA)? Ships on the oceans often remain in port for periods of time. And we could use a spaceship in orbit as a space station if no trip to the Moon or Mars was ready.
How much time does a space ship take to reach Mars?
To date it has ranged from 131 days (Mariner 7) to 334 days (Mars Polar Lander). It will vary based on the positions of Earth and Mars in their orbits for that opportunity, i.e. each can be further or closer from the Sun and the relative inclination will vary, the energy available from the launch vehicle, the launch date, the desired arrival conditions (e.g. lower velocity for orbiters), and the chosen trajectory type (Type I is a bit less than a half orbit around the Sun, Type II is a bit more than half an orbit). Within bounds, the transit time is a choice made by the mission designers to meet various constraints. A common constraint for planning convenience is to keep the same arrival date across the launch period, hence the number of days will depend on which day you get the launch off.To zeroth order, minimum energy transit times are around half of a Hohmann transfer orbit from Earth to Mars. That can be calculated for the mean solar orbit radii of Earth and Mars with departure and arrival at the same inclination to be 259 days. The mean of the trips to Mars so far is about 250 days.How long a mission in the future will take depends on all of those factors. Most importantly, if you are willing to spend more energy, and you can accept a high arrival velocity, you can get there faster. Human mission plans typically try for 140 to 180 days to reduce human exposure to radiation and reduce life support supplies.
What is the orbital period of a spacecraft in a low orbit near the surface of Mars?
Spacecraft have been sent to Mars in recent years. Mars is smaller than Earth and has correspondingly weaker surface gravity. On Mars, the free-fall acceleration is only 3.8m/s2 . What is the orbital period of a spacecraft in a low orbit near the surface of Mars? Assume the radius of the satellite's orbit is about the same as the radius of Mars itself, rMars = 3.37×106m .
How long does it take to receive an image from a spacecraft (rover on Mars)?
How long does it take to receive an image from a spacecraft (rover on Mars)? Let’s say the Mars Science Laboratory rover Curiosity takes a picture. There are two ways we can get that picture. One, Curiosity can send the data right to earth using her own high-gain antenna. Unfortunately, the data rate for this method is very, VERY slow. Much slower than dial-up internet for those of us old enough to remember. If I recall, it is on the order of one kilobit per second. That alone means it could could take upwards of several minutes just to transfer the data. In this case, as long as Mars has rotated to a position where Curiosity is on the side of Mars facing earth, there will not be any wait or delay in sending. If the rover is on the “wrong side” of Mars, it could be about 12 hours before she is in a position to send us the data. Here is a picture of the High-gain antenna:The other way, and much preferred method is to uplink the data to one of the Mars-orbiting spacecraft such as the Mars Reconnaissance Orbiter. In this case, since the orbiter is, well, orbiting, the rover may have to wait up to an hour for the orbiter to rise above the horizon. Transferring the data to the orbiter is pretty quick and over a very short distance, so that will only take a few minutes, depending on how much data needs to uploaded. After the orbiter has the data, it then needs to send the data to one of the earth ground-based antennas known collectively as the “Deep Space Network”. Since there is a lot of demand for those antennas, there could be a delay while waiting for her turn. It could be anywhere from no delay at all to a few hours until an antenna is ready to receive the data.In any case, the travel time for data from Mars to Earth (or vice versa) ranges from 20 minutes to 40 minutes, depending on where Mars is in its orbit compared to the Earth. For instance, if Mars is on the other side of the sun, it will take the longer trip.All things considered, it could take as little as 30 minutes to get a photo from the Curiosity rover, or it could take more than a day depending upon the availability of the different communication pieces that I talked about above.Here’s more information on comms between Mars to earthCommunications - Mars Science Laboratory
A small space probe of mass 260 kg is launched from a spacecraft near Mars. It travels toward the surface of?
Mars, where it will eventually land. At a time 22.7 seconds after it is launched, the probe is at location < 5800, 8600, 0 > m, and at this same instant its momentum is < 42000, -7800, 0 > kg•m/s. At this instant, the net force on the probe due to the gravitational pull of Mars plus the air resistance acting on the probe is < -4850, -840, 0 > N. Assuming that the force is nearly constant during the time interval from 22.7 seconds after the probe is launched to 23.1 seconds after the launch, so that the velocity is changing at a constant rate, what is the change of the position of the probe during this time interval? What is the location of the probe 23.1 seconds after launch?