68

Edit: The JPL Mars Helicopter Scout will use inertial navigation: The inconsistent Mars magnetic field precludes the use of a compass for navigation, so it will use a solar tracker camera integrated to JPL's visual inertial navigation system. Some additional inputs might include gyros, visual odometry, tilt sensors, altimeter, and hazard detectors.[15] ...


47

NASA formed a board to investigate the loss of the spacecraft and reached some high level conclusions. The board cited a number of contributing factors, which I have filtered to include the ones most relevant to the question: errors went undetected within ground-based computer models of how small thruster firings on the spacecraft were predicted and ...


31

GPS is one of several possible technologies available for assisted navigation. It's commonly used on commercial drones because the framework is in place and GPS signal is usually available on Earth. It requires a flotilla of satellites around our planet to work, though - something we don't have (yet) around other celestial bodies. In that case we need ...


25

There were a good number of chances to catch the error after launch, which is what most of the reports on the mission focus on. To look specifically at what testing was done before launch this paper from the American Astronautical Society has a decent overview, starting on page 6: The failures of the Mars Climate Orbiter and Mars Polar Lander: a perspective ...


18

Not the way GPS works, no, since the Mars orbiters don't have atomic clocks. (Though future Mars orbiters may someday.) The relay radios on the Mars orbiters provide a 2-way Doppler data type that can be used to locate surface assets to, as I recall, within about 100 meters. Even a single orbiter with Doppler data collected over a few passes can get this ...


16

I've reused some material from this answer here to show that the MARS 2020 rover will land on Mars using optical navigation in part. A helicopter can use similar environmental learning techniques developed for robots on Earth. This isn't a perfect example, but it gives the idea that the robot builds up a map over time. At each point you can identify the ...


15

Either prograde or retrograde entry is easy to achieve; the choice of trans-Mars trajectory can put the spacecraft slightly ahead of Mars' position at arrival (yielding retrograde orbit) or slightly behind (prograde). A midcourse correction maneuver of about 1 m/s ∆v can make the difference. For Apollo, the retrograde entry was, I think, needed for the free ...


12

In general, (.*)stationary orbits are simply the altitude where a circular orbit has a period equal to the rotational period of the central body. In order to find this altitude, we can transform Kepler's third law to solve for R: Kepler's third law: $\frac{T^2}{R^3} = \frac{4\pi^2}{G M_{central}}$ Solved for $R$: $R = \sqrt[3]{\frac{T^2 G M_{central}}{4\...


10

Mark Adler already explained that the satellites aren't equipped anyway to provide a satellite navigation system. But even when they were technically capable of working as a GPS satellite, 5 satellites would not be enough. You need a direct line of sight to at least 4 satellites, and with only 5 satellites this will happen very rarely, because even ...


9

Other than taking images of Mars' moon Deimos far side (something not done in decades) not much has been attributed to MOM yet. The key here is to remember that the the orbiter likely won't discover anything per se, but the science data it produces can be used (probably in conjunction with other data) to help us understand the history of Mars. Here is an ...


6

Such an orbit is called an areostationary orbit. It's possible; the orbit would be about 17,000 km above Mars's surface. It's never been done, though.


6

It seems pretty likely that it is still in orbit. MRO is in an orbit of about 370-400 km, which is quite low, but still doesn't use significant fuel to keep it up. 250 km is considered too high for aerobraking. Almost certainly Viking 2 is still orbiting Mars, probably in a similar orbit to what was last known. The only real question is if sunlight pushed it ...


5

The amount of propellant required to achieve a certain delta-V is dependent on the ratio between the starting and ending mass of the spacecraft, according to the Tsiolkovsky rocket equation; a given thruster and fuel supply will get you more delta-V on a smaller spacecraft and less delta-V on a larger one. That is, 0.058 km/s per kg is not an inherent ...


5

Inertial navigation with occasional "fixes" to reset position to within desired accuracy limits. Fixes can be photos of ground, positions of stars, radio triangulation or input from external tracking stations, not just satellites. An inertial platform will have gyros for rigidity, accelerometers to sense changes in velocity (acceleration) and gimbals to ...


5

I think they had an issue with the methane sensor. From India's Mars Orbiter Mission Has a Methane Problem: The problem has to do with how the instrument collects and processes detections of methane in the atmosphere, a technique known as spectroscopy. "Imagine that you hold your hand in front of you and extend your four fingers ... Suppose that ...


3

Big organisations have big cracks for things to fall down. NASA has the additional problems of: There not being much precedence for most of the things they do. They only getting one shot at it most of the time. In such case the big ticket items, are typically well taken care of. If it's clear what the question is and there is the potential for get it wrong ...


3

[Update: This information has been superseded by more recent info, which challenges the operational value of the sensor data. See the other answer.] As of March 2015, the Mars Orbiter Mission (MOM) methane sensor has been working, but has not detected any methane. ISRO has released some data on the operations so far. Emily Lakdawalla explains: The map ...


3

Radar, ground mapping techniques, accelerometers and many other ways to get a relative idea of where you are.


2

An Austrian university is working on that right now. They use an onboard camera for the navigation (see below). Also, a recent drone on Kickstarter uses odemetry for positioning. The project did not end that well, but on windless days, if there are no problems, the drone works: See here From Alpen-Adria-Universität Klagenfurt's Researchers from Klagenfurt ...


2

These objects aren't of particular interest at the moment, as we would have a hard enough time reaching Near Earth asteroids. However, they offer some potential benefits in the future, namely: They could provide orbital resources for Mars for fuel and such. They could assist in transforming Mars (Impacts could provide useful resources, for instance.) ...


2

Wikipedia article says but the wikipedia itself is not "reliable source" of information. I will try to list several sources about MARPOST (russian МАРПОСТ) here. 4 sources from wiki article: RIA 03/2005: RUSSIA SUGGESTS MANNED MARTIAN-MISSION PLAN: "It will take 10 - 12 years to implement the MARPOST project with annual expenses totaling nearly USD 1.5 ...


1

In addition to the C3 for any given pair of departure and arrival dates, you will also need to know the departure declination for that pair. (The Lambert solver you are using must be generating that as well.) You then want to optimize mass delivered to the interplanetary trajectory. If the departure declination is less than the latitude of the site, then ...


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