Questions tagged [mission-design]

Mission design is the process of designing a spacecraft to fulfill a particular objective.

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NASA GMAT: Any good tutorials or methods to learn how to use patch points and control points to come up with viable and optimal trajectories?

I'm a beginner to trajectory design, and have to use NASA's GMAT software. It's been a few weeks now, and I have done the first four tutorials and managed to create a (very unrealistic and sub-optimal)...
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How is the moon's orbital motion accounted for in determining the best observation platform/location for JWST at L2?

The moon's periodic motion would appear to impose a perturbation to the otherwise equilibrium state of the solar/earth L2 point.
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For JWST's "29.5 days of terror" before orbital insertion, unfolding the sunshield is the scariest for me. When is this scheduled to happen?

At what date and time UTC is JWST's unfolding of its sunshield scheduled to begin? At what date and time UTC is confirmation of success expected if all goes smoothly?
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How the number of Sun sensors is chosen for a given spacecraft and mission?

I have to study an ADCS sensors suite and I am struggling to find a criteria to decide how many and in which directions the sun sensors shall be mounted, considering that they are coupled with star ...
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Closest approach between the JWST launch vehicle and Santa Claus's sleigh?

This ABC News video describes how for the 66th year in a row NORAD will be tracking Santa Claus's progress. This year they will have to contend with a potential conjunction between Santa's sleigh and ...
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How would a repair of the JWST proceed if it were ordered regardless of the cost and technical hurdles, depending on when/how it fails? [closed]

I have heard people speaking about how, unlike Hubble, the James Webb Space Telescope is "one of a kind", "not designed to be repaired", "not serviceable", and the like, ...
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"Hohmann-Like" and Chemical / Electric Thrust Comparison

Part of the work I have to do for my degree is to perform a "Hohmann-like" transfer between Earth and Mercury, of which I believe I have accomplished. I have attempted numerous times to ...
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Why does JWST need "a carefully designed series of oscillations" to avoid overheating during the 2nd stage burn? Why not rotate "rotisserie style"?

The Northrop Grumman video James Webb Space Telescope Launch and Deployment describes the trajectory from launch to orbital insertion and illustrates several key maneuvers and incremental steps in the ...
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Why is 90 sols a standard mission duration for robotic spacecraft on the surface of Mars?

Several robotic Mars surface missions have a planned mission duration of 90 sols. I would like to understand why this specific mission lifetime is commonly used by mission planners. Below is a non-...
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Why doesn't JWST use ion thrusters?

Since the L2 point is unstable, JWST needs engines to maintain its orbit. It uses mono-propellant engines which have given it a 5-year minimum lifespan. Why weren't ion engines used instead? Wouldn't ...
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How much more does it cost to produce two identically designed probes/rovers/satellites compared to making only one?

There are a number of historical planetary missions that have produced 2 flying instances. Examples include Voyager, Viking, MERS, some of the Mariners missions. Other missions have only one ...
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Why did the last six TDRS satellites start at ~7° inclination on a downward trend that appears to be "repelled" by zero & bounce back w/o crossing?

The most recent six TDRS satellites (8 through 13) were inserted into moderate inclination orbits of roughly 7°, and in all cases their inclinations immediately decreased at rates of about +/-1 or +/-...
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Has ion propulsion ever been used in a deep space trajectory correction maneuver proper?

Answer(s) to What types of propulsion are used to adjust an orbit? lead me to wonder if electric propulsion has ever been used for a proper TCM or "trajectory correction maneuver" in deep ...
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How will DART be able to hit a 170 meter rock dead-center at over 6000 m/s? What technologies will be use and how will they work together?

The DART spacecraft will ultimately be a kinetic energy impactor, using its 500 kg mass at a relative velocity of over 6000 m/s to slightly change its target 65803 Didymos's companion Dimorphos's ...
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Deep space marksmanship; will DART's intercept and impact trajectory represent the best ever if successful? If so, by how much?

The DART spacecraft will ultimately be a kinetic energy impactor, using its 500 kg mass at a relative velocity of over 6000 m/s to slightly change its target 65803 Didymos's companion Dimorphos's ...
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How does a 22 dBi X-band "patch" antenna get so much gain and how well behaved is its high-gain radiation pattern?

@NgPh's answer to How will the LICIACube cubesat transmit DART impact images back to Earth? What kind of antenna and radio will it use? quotes LICIACube on DART mission: an asteroid impact captured by ...
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Are any space agencies working on an (essentially) 100% reliable sterilization technique for spacecraft bound for subsurface ocean worlds?

One answer to my previous question Is there any demonstrated or even proposed technology that can sterilize a spacecraft with 100% certainty and yet leave it electronically functional? asserts: ...
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Could the International Space Station (ISS) be refurbished to save money?

I was reading an old article about deorbiting ISS (Death Star: The ISS Doesn’t Have a Way to Crash Safely) and wondering if we could refurbish ISS instead of deorbiting it? I thought deorbiting it ...
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How to use the Util and Base Code of the General Mission Analysis Tool

GMAT (General Mission Analysis Tool) provides detailed Util and Base Code, but I don't know how to use it, namely I still don't know how to access so many data of some missions. Can somebody provide ...
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How exactly did Cassini provide rock-solid attitude control to enable high resolution low light imaging? (1.2 arcsec/pixel for narrow angle camera)

The extremely cool NASA JPL video Triumph at Saturn (Part I) is really worth a watch and/or listen. At about 45:45 it discusses the period after SOI (Saturn Orbit ...
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Which deep-space spacecraft flew closest by Earth during a gravitational assist?

The extremely cool NASA JPL video Triumph at Saturn (Part I) is really worth a watch and/or listen. (Don't forget Part II as well!) At about 26:30 it discusses ...
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When was Lucy's mission first scripted in Excel and why is that what Lockheed Martin chose to do it with?

CNBC's NASA spacecraft launches toward Jupiter asteroids on an intricate path charted by Excel Years before Lucy took off, Lockheed Martin mission architect Brian Sutter used Excel to chart the ...
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Why put SunRISE in the graveyard? Why will it "fly slightly above geosynchronous orbit"?

The blots.nasa.gov article NASA’s SunRISE Mission Studying Solar Particle Storms Moves Toward Launch says that the upcoming SunRISE mission — short for the Sun Radio Interferometer Space Experiment — ...
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Just how preferable are afternoons for flying Ingenuity? Why?

JPL tweet links to mars.nasa.gov's Flying on Mars Is Getting Harder and Harder which explains that seasonal changes are lowering the density of the local atmosphere, presumably due to warmer seasonal ...
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How do Spaceship navigate in space?

In Space there is no air to put thrust on any other thing to expect any action-reaction forces. Then how do spacecraft go left or right or are the ineligible to take sharp moves?
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What factors would contribute to a spacecraft's ability to maintain a very low orbit (VLEO) or at least orbits with very low perigees?

I asked What does account for a high coffin corner of a plane? in Aviation SE. Now I wonder what factors would contribute to a spacecraft being able to maintain low circular orbits (e.g. within 200 km ...
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Why are the four launch opportunities within each Inspiration4 launch window "about an hour apart"?

In the SpaceX Inspiration4 Launch broadcast at about T-01:31:05 (91 minutes before launch) the process for selection of launch windows for the mission is roughly ...
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Design and optimization of a Sun-synchronous repeating ground track orbit constellation

I am currently researching about this topic and am very new to this. Have no clue how to go about designing a group of imaging satellites (constellation) that are sun synchronous with repeating ground ...
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Space settlement in Jupiter [closed]

Would a space settlement located in one of the orbits of Jupiter be economically feasible? According to me, it would be quite profitable in the long run, as 1) The settlement can act as a pit stop for ...
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How did Japan’s Hayabusa 2 mission "make extensive use of deployable cameras to get scientific imagery"? Did it ever produce a "PR selfie"?

Scott Manley's recent video China's Mars Rover Zhurong Has Completed Its Primary Mission, Reaches New Milestone includes the following: And if you thought that dropping a camera on the surface of ...
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After inserting CAPSTONE into a "highly efficient ballistic lunar transfer trajectory" Lunar Photon; to what separate orbit for its safe disposal how?

NASA Ames's feature CAPSTONE’s CubeSat Prepares for Lunar Flight says CAPSTONE will use a hydrazine-fueled propulsion system during most of its three- to four- month journey to the Moon. This line of ...
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Is there a fairly detailed outline of CAPSTONE's "highly efficient ballistic lunar transfer trajectory" from LEO to lunar near-rectilinear halo orbit?

NASA Ames's feature CAPSTONE’s CubeSat Prepares for Lunar Flight says CAPSTONE will use a hydrazine-fueled propulsion system during most of its three- to four- month journey to the Moon. This line of ...
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Exactly why does Starship need to be this big for interplanetary travel?

As discussed in several answers to Isn't Starship way too big? Starship's unusual size is due to it being intended for missions to the Red Planet. But why? Even a smaller ship could satisfy the ...
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what kind of valves are used in payload fairing for venting?

I wanted to know that there have been a handful of literature that mentions vent openings in the rocket payload fairings. However, none specify the kind of valves used in those fairings? does anyone ...
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Can we land on an asteroid and ride on it?

If we could land on an asteroid, not necessarily a human, we would save the fuel consumed for flying the spacecraft and we will benefit by having the systems on it running for a very long time.. If ...
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Most dog-legged launch?

There are enough questions about dogleg maneuvers that there is now a dogleg tag, but the definitive dogleg answer is @JakeBlockers (linked below) which includes images of a dogleg from Florida that ...
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Closest distance that two unrelated spacecraft have come while both in heliocentric orbits?

In 2015 STEREO A and B passed each other passing roughly behind the Sun at the same time from opposite directions as seen from Earth. But these two are part of a single mission, put into these orbits ...
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Why was the Rossi X-ray Timing Explorer decommissioned in 2012? Why wasn't it deployed another ~100 km higher where drag would have been a lot less?

The Rossi X-ray Timing Explorer (1995-074A) was an incredibly prolific space telescope between 1996 and when it was decommissioned/deactivated on January 5, 2012. It reentered the atmosphere soon ...
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Flyby puzzler; starting from Earth, how many times can you use Jupiter flybys in one century?

Is there any limit to how many times you can increase velocity by repeated sling shot manoeuvres? and its answers have got me thinking, and that's always dangerous. Suppose you have a durable RTG-...
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How (the heck) can thrusters alone stabilize New Horizons well enough to take high magnification 30 second long exposures in order to see +21 m objs?

Wikipedia's Long Range Reconnaissance Imager says that LORRI is a: ...telescope aboard the New Horizons spacecraft for imaging. LORRI has been used to image Jupiter, its moons, Pluto and its moons, ...
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What is this block of long, skinny rectangles in this New Horizons trajectory/operations simulation?

This answer to What do all these vectors point to in this New Horizons trajectory/operations simulation? begins: The software is definitely AGI's STK (notice the font and the states at the left top ...
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Into what non-navigable Pacific Ocean area did structural elements of the Progress MS16 cargo ship & Pirs module fall? Are there maps of these areas?

This recent Roscosmos tweet (found in CNET's See astronaut's wild view of a discarded ISS module burning up) says: The non-combustible structural elements of the #ProgressMS16 cargo ship and the #...
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Why did Unity 22 flight plan call for such a large horizontal velocity during its weightless phase? (1085 kph) Why not go straight up instead?

A quick check of the videos shows Unity 22's apogee of over 86 km, and at that point the displayed speed is 674 mph or about 1085 kph or 18.1 km per minute. During the four minutes of being weightless ...
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Unity 22's ground track; which direction was it moving horizontally at 1085 kph during its weightless phase?

update: According to The Newyorker's The Red Warning Light on Richard Branson’s Space Flight there is FR24 data available. A quick check of the videos shows Virgin Galactic's Unity 22's apogee of ...
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How could Starship "deep space variants" improve payload performance by "orders of magnitude" (Elon Musk)?

Replying to Scott Manley's tweeted table of payload mass for a given geocentric C3, Musk tweeted: We could stretch the Falcon Heavy upper stage & increase this a lot, but FH already covers all ...
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From what altitude will they cut Dragonfly helicopter loose on Titan and make it land itself, and what are the main factors determining this altitude?

Titan's surface pressure is about 1.5 bar and because the surface gravity is low pressure falls off much more slowly with altitude than it does on Earth. From Wikipedia's Atmosphere of Titan; vertical ...
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Was there any launch vehicle possible that could have been used for a heavier New Horizons with enough fuel to enter Pluto orbit? (adding ~10 years)

Answers to the Astronomy SE question Can New Horizons probe turn back and start orbiting Pluto are of course no, it would have to have been a different mission with a lot more fuel and a bigger launch ...
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Why did the space shuttle's altitude go down after reaching 108,000m?

I recently took a look at this little data sheet by NASA: Math and Science @ Work; Space Shuttle Ascent Time Altitude Velocity Acceleration Comment (s) (m) (m/s) (m/s^2) 20 1244 139 18.62 40 5377 ...
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For a crew-mission, in case of impromptu changes, what would be the most suitable depot locations for a re-supply?

Following the question on re-fuelling en-route to Mars, I am interested in exploring a mission architecture in which a crew may be offered different options for impromptu mission changes, for example ...
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Premature detonation of explosive bolts when landing on hot Venus?

@Uwe's comment below Parachute material used for the Venera probes to survive 500 °C raises an interesting issue. Venus is really hot, and pyrotechnic actuators (e.g. explosive bolts, frangible ...

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