astrosnapper
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Does NASA have an end-of-the-world policy?
53 votes

First off, large life-ending asteroid impacts are very rare as there aren't many of them out there and we've found almost all of them: Looking at the 'continent' and 'global catastrophe' areas of ...

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Why are we interested in visiting the giant planets' icy moons?
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34 votes

The icy moons are of interest for exploration as part of the overall "follow the water" strategy of exploration that NASA (and others) have been exploring for some time. The "where else can water be ...

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Why was Canberra able to listen to Voyager 2 but not talk to it?
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19 votes

As per the March 4 JPL News story, only DSS43 has the right S-band transmitter, enough power and is in the right hemisphere to talk to Voyager: Moreover, a special S-band transmitter is required to ...

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How can stellar images be "subtracted" from a sequence of exposures? (difference imaging)
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14 votes

The principles of Difference Image Analysis (DIA) or Difference Imaging, which is very common in modern astronomy for finding new transient sources (e.g. asteroids, variable stars, including ...

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What is the purpose and necessity of this giant structure being used in tests of China's Mars lander?
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10 votes

According to Quanzhi Ye (via tweet; while not a primary source, he is planetary scientist who understands Chinese) it is for simulating Mars' lower gravity while testing obstacle avoidance for the ...

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When was the last time that Starman/Roadster was seen?
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9 votes

@uhoh's answers are correct in that we at LCO were the last to observe the Tesla Roadster. For some reason, a Distant Artificial Satellites Observation (DASO) circular was not issued in the March 2018 ...

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NEAR Shoemaker mission data
6 votes

All the data from the NEAR Shoemaker mission is archived at the Small Body Node of the NASA Planetary Data System. Asteroid surface properties (the regolith) is normally measured using images or ...

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What is the closest distance SpaceX's Tesla Roadster (Starman) will ever be to Mars?
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6 votes

Putting the spacecraft id (-143205) into the JPL HORIZONS ephemeris system produces: TRAJECTORY: This trajectory is based on JPL solution #10, a fit to 364 ground-based optical astrometric ...

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Precision in the space navigation
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5 votes

The current best ephemerides available is the JPL DE440 as described in Park et al. 2021 (paywalled) and available from the JPL ftp site. This is an incremental improvement over the previous DE430 ...

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Skyfield, how to use https:// instead of ftp://?
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5 votes

Looks like this was an issue that was fixed and closed recently so try updating your copy of Skyfield to at least version 1.31.

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What is the closest asteroid to Earth worth mining?
4 votes

The list doesn't specify a distance to the Earth (the "ground") because this is always changing as the asteroid travels around its orbit. You can get an idea of the asteroid's orbit using the JPL ...

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What are InSight's barometric and seismic digitization rates and frequency responses when it "listens to the wind"?
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4 votes

The page at the NASA Planetary Data System Planetary Atmosphere Node on the Temperature and Wind for InSight (TWINS) instrument and Pressure Sensor (PS) has a description of the instrument and data ...

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Are there any specific plans for how to deal with near-Earth comets? If not, should there be?
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4 votes

The threat from comets gets a lot less attention for several reasons: the threat from comets is about 1% of that from asteroids (executive summary of the 2017 Report of the Near-Earth Object Science ...

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Where to find raw images of Ultima Thule?
4 votes

All the New Horizons data is archived and available at the Small Bodies Node (SBN) of NASA's Planetary Data System (PDS) at this landing page. PDS is the main official repository for all NASA ...

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What is $\theta_{GMT}$?
3 votes

$\theta$ is often used as the symbol for sidereal time e.g. in this Sidereal Time article on Navipedia. The subscript $_{GMT}$ is probably referring to Greenwich Mean Sidereal Time, albeit ...

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How to convert a SPICE SPK kernel into human-readable data using SPICE toolkit and utilities
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3 votes

So I am using the following layout for my SPICE kernels (not essential but matches tutorial recommendations, adjust paths in the spm2oek input file as needed) ├── bin │   └── spk2oem ├── kernels │   ├─...

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What is the name of the new NEO searching telescope "heavily based on" NEOCam? (now NEO Surveyor)
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3 votes

The new mission is going to be called NEOSM for NEO Surveillance Mission according to Twitter messages from committee members (example) or this Arstechnica article - which isn't a lot to go on. More ...

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If a comet-sniffing spacecraft were launched today, could it catch up to newly-discovered ε>3 C/2019 Q4 (Borisov)?
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3 votes

Not a chance. As detailed in Bill Gray's FAQ for C/2019 Q4, the velocity at "infinity" when it leaves the Solar System will be ~32.6 km/s, one of the strongest signs that this was an interstellar ...

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What is mast camera? And what does it do?
2 votes

The Mastcams (there are 2) on the Mars Science Laboratory aka Curiosity were built by Malin Space Science Systems and use similar components to the other imagers on Curiosity such as MAHLI and MARDI. ...

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JPL ephemerides: effect of Saturn, Uranus and Neptune
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2 votes

The equations of motion for how bodies move in the Solar System, which are then fitted to the observational data of positions and ranges to provide the ephemeris, involve a nested set of effects which ...

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Are there any equations out there that can calculate the burnup of an asteroid depending on angle?
2 votes

The Purdue University Impact Earth! site will calculate this for you. Clicking on the Documentation link will give you the paper of formula and approximations that are used. The equation for the ...

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How exactly to use astroquery.jplhorizons to get the state vectors of Mercury and the Parker Solar Probe?
1 votes

Not sure exactly what you want as the origin and what corrections for aberrations are wanted and whether you want Mercury itself or its barycenter but there didn't appear to be much/any difference in ...

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How to determine the distance between where Earth and Mars are two specific dates?
1 votes

Stellarium is a general planetarium program which is available for Linux, MacOS X and Windows and is pretty easy to use. Moving the mouse to the left side of the screen pops out options to change the ...

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