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16

There is a map of lunar pits, created by R. V. Wagner and M. S. Robinson of the School of Earth and Space Exploration, Arizona State University, in 2014. From Distribution, Age, and Formation Mechanisms of Lunar Pits (PDF) by mentioned authors: Map of the locations of all currently-known pits. Orange stars indicate mare or highland pits, and blue ...


15

Introduction to selecting a reference surface The surface of any celestial body can be anything but uniform. The oceans, where existing, can be treated as reasonably uniform, but the surface or topography of the land masses can exhibit large vertical variations between mountains and valleys. These variations make it impossible to approximate the shape of ...


13

If you mean if New Horizons' data return could produce a global high-resolution map of Pluto's surface, then no, and here's why: Pluto at New Horizons approach: New Horizons Ground Track on Pluto: Source of both images is Alan Stern's (New Horizons PI) presentation (PDF) to OPAG Meeting in July 23, 2014. As you can see, on New Horizons' close approach, ...


11

Mars Reconnaissance Orbiter has a camera called HiRISE (High Resolution Imaging Science Experiment), launched in 2005-08-12, which is the highest resolution camera in orbit of Mars at an altitude that varies from 200 to 400 kilometers (about 125 to 250 miles) above the martian surface by Carrier rocket Atlas V-401. The High Resolution Imaging Science ...


9

There are many different coordinate systems (X, Y, Z axes as you refer to them). The center of the Earth is often used as the origin "center" of the coordinate system, at least for calculations concerning the space in the vicinity of Earth. There are many such Earth-centered coordinate systems as well. In the Space Shuttle Program we used the "Mean of 50" ...


8

Today, our highest-resolution gravitational maps of the Earth are from the Gravity Recovery and Climate Experiment (GRACE) project, launched in 2002. That's not the case. The latest GRACE gravity model, which combines results from the GRACE and GOCE gravity missions and DTU13 is a 360x360 (degree and order) gravity model. On the other hand, the EGM2008 ...


8

The standard for any tidally locked body, of which Europa is a member, is to have the 0 longitude be the point at the center of the planet-facing side. That being the case, the middle of the map should be the portion facing Jupiter, the edges the part that never faces Jupiter. See Wikipedia for the referenced quote below: Tidally-locked bodies have a ...


8

Here is a nice graph of part of what you are asking for. It's from the book Satellite Orbits; Models, Methods, Applications by Oliver Montenbruck and Eberhard Gill, Springer, 2000. The figure and description can also be found in google books. It shows the magnitude of some major perturbations acting on a satellite in earth orbit from LEO to GEO. This paper ...


6

It's referring to the plain old Lunar Orbiters of the 1960s. Boeing manufactured the spacecraft for NASA. According to NASA's Destination Moon: A History of the Lunar Orbiter Program, Boeing (in collaboration with Eastman Kodak) was one of 5 companies that responded to NASA's call for proposals, and the one that was ultimately chosen for the project.


5

There is an effort to map Earth's gravity, GRACE, which has been ongoing since 2002. It's produced this: Neat, right? Several GRAIL-like missions are planned / in progress / completed. Mars Express. LISA, a probe designed to measure gravitational fields in space, with hopes of finding black holes. Magellan mapped Venus' gravitational anomalies. MESSENGER ...


5

For Mars, the current definition of 0 km is derived from data from the Mars Orbiting Laser Altimeter (MOLA) data from Mars Global Surveyor. In fact the altitude reference is referred to as "MOLA altitude". You would say for example: "minus 1.4 km MOLA". From the paper: Zero elevation on Mars from MOLA is defined as the equipotential surface (...


5

The question, 'Did they remove 4 atlases?' can only be answered by an insider. NTRS does not show documents that have been removed. However, a search for '"Lunar Orbiter" atlas' shows lots of results including "Lunar Orbiter Photographic Atlas of the Moon" - a 500 Mb PDF with loads of photos. So they didn't systematically remove Lunar Orbiter results. ...


4

Most weather balloons can go up to about 40 km. At that altitude, the pressure is about 2.9 millibars. The Martian atmosphere is about 6 millibars at surface level. At the summit of Olympus Mons (21.25 km) the pressure is about 0.3 millibar. That would set 2.9 millibar at about 9.8 km above the Martian surface. The record for highest high-altitude balloon ...


4

The polar regions aren't filled with useless texture - it just isn't very accurate. I have done the exercise you are going through. I'm pretty sure that data package is the best that exists, and better data won't be coming along any time soon. Here's what I did. I adjusted the top and bottom of the map to better match the rest. Yeah, that's just fudging. ...


4

It depends on where the masscon is in relation to the orbit, and just how big the masscon is, as well as how carefully the orbit is measured, and whether or not anyone is actually looking. If it's a polar impact and an equatorial orbit, it would need to move the center of mass appreciably to be noticed at all. If it's an equatorial impact and a polar orbit,...


4

tl;dr Those numbers are meters per pixel. But you have to be careful because they are scans along the spacecraft orbit with the moon rotating underneath, so x and y are skewed. This answer will get you started. The LRO is an amazing spacecraft with a wide variety of instruments to map the moon's surface by a number of characteristics as well as ...


4

Here's the link: http://moon.bao.ac.cn/searchOrder_dataSearch.search You may need to create an account. Scientific Data -> Search -> find your data and download. The website is extremely slow, and not user friendly at all. The search page is so slow, may take 30-180 seconds to load. The download link looks like: http://moon.bao.ac.cn/cedownload/CCD/...


3

It was the Earth, of course. As early as 1964, scientists realized that the non-Keplerian orbits satellites gave a picture of the Earth's interior. For example, see S. K. Runcorn, "Satellite gravity measurements and a laminar viscous flow model of the earth's mantle," Journal of Geophysical Research 69.20 (1964): 4389-4394.


3

One need look no further than the Moon. There were (and to some extent still are) some rather severe internecine wars within the Jet Propulsion Laboratory on the "right" way to represent the Moon's orientation. One group insists that the right way to describe the Moon's orientation is via its principal axes (the MOON-PA point of view). Per this point of ...


3

Balloons can be quite useful for carrying scientific payloads, but only on Earth, Mars or something else "benign". Not Uranus though. In that context, it's more science fiction (of the remote future, that is) than a serious design consideration. They are a poor design choice because: They are completely useless for the duration of the rest of the mission ...


3

Google Maps Moon likely uses a Simple Cylindrical projection for storing their map data. This is fine for the majority of the globe, but there are problems at the poles. Here are a few reasons why imagery of the poles is problematic: The data is prone to discontinuities because it has the entire top or bottom edge of the rectangular projection converging on ...


3

There are a couple of ways these can come. In the case of the image you provided, I believe they are using known altitude that comes from MOLA data which accurately found the elevation of the entire Martian surface, and using that to transform the image as it was. They are likely using some terrain features from the image to determine it's altitude as well. ...


2

The Gravity Anomaly or Bouguer Anomaly Maps are no actual gravity maps. They are rather a map of ground density, expressed as an excess or deficit of gravity caused by differences in density. The maps are the result of measuring the gravity and subtracting all effects of oblateness, terrain shape, terrain height and so on. The result is a map of differences ...


2

The strong distortions and star-like stripes are an artifact of Googles' image processing. For comparison, here is a screenshot of our own South Pole : I increased the contrast to make the artifacts more visible - the ice itself just has less contrast than the rocky features of the Moon.


2

The lighting is different at the poles. The sun is always very close to the horizon. There are some crater floors at the poles that never see sunlight. These crater floors are always inky black. Likewise there are polar plateaus and mountain tops that enjoy nearly constant sunlight. Shadows cast across these plateaus are always long though. And these long ...


2

As advised by @uhoh we can visit the site mentioned in his comment mars.nasa.gov/maps/explore-mars-map/fullscreen go through the tutorial, search for and locate the areographic features and place balloon markers on the same. Worked for me.


2

The reference datum is usually chosen to be about the average altitude. For example, on Mars, the datum, known as the Mars areoid, is very close to the average radius of Mars, as measured round the equator. (It was defined by the height at which the pressure corresponds to the triple point of water.) In reality it wouldn't matter very much what the ...


2

I find the accepted answer unclear, so I'll try: The two maps in discussion use coordinate systems based on the convention that 0 longitude is the point directly facing Jupiter, but they have chosen to put that point on the far right-hand edge of the map. Dyfed Regio is on Europa's Trailing and Anti-Jovian hemispheres (not the Sub-Jovian). Note that the ...


2

I am not aware of any particular standard for the primary body, however for the Pluto system, in this image the 0,0 point is on the opposite side of the hearth: And in this image, the hearth is shown to also be at the opposite side from Charon. So I assume you are right.


1

The answer by @OrganicMarble really sums up the situation well! I'm going to add this supplemental information here only because it won't fit into a comment. The documentation of Skyfield discusses Barycentric position - i.e. position of things with respect to the center of mass of the solar system, which is approximately at the sun, although because ...


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