Proper Motion from Tangential Velocity Inverse Converter
Inverse transverse velocity/distance to total angular motion inmas/Julian year; no radial motion. Caller independently establishes frames, units, epoch, covariance and instrument context; not an identity, association or astrometric quality certification.
Description
Tangential speed and distance can be inverted to obtain angular proper motion.
Tangential speed and distance can be inverted to obtain angular proper motion.1
The speed must be a transverse component under the same distance convention. Use Proper Motion from Tangential Velocity Inverse Converter to evaluate the supplied inputs under the model explained below.
When to use Proper Motion from Tangential Velocity Inverse Converter
Use Proper Motion from Tangential Velocity Inverse Converter to evaluate the supplied inputs under the model explained below. Establish the units, measurement scope and model assumptions before entering values.
How to use Proper Motion from Tangential Velocity Inverse Converter and understand its results
- Establish the units, measurement scope and model assumptions before entering values.
- Enter Tangential velocity km per second, Distance parsecs using the field table and validation rules below, then run the tool.
- Read Proper motion mas per julian year; interpret the units, signs, ordering and unknown-value placeholders described below.
- Correct reported input errors and rerun. Apply successful results according to their specific meanings and check the assumptions before using them in a decision.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| tangentialVelocityKmPerSecond | Tangential velocity km per second | number | Required; constraints below |
| distanceParsecs | Distance parsecs | number | Required; constraints below |
Enter nonnegative tangential velocity in km/s and positive distance in pc. Return 1000×velocity/(4.740470463533486×distance) in mas per Julian year. Zero speed returns zero; no radial component or distance inference occurs.
properMotionMasPerJulianYear=1000×tangentialKmPerSecond/(4.740470463533486×distancePc) Use the field order, units and branch conditions described above.
| Output field | Meaning | Value type |
|---|---|---|
| properMotionMasPerJulianYear | Proper motion mas per julian year | number |
{
"input": {
"tangentialVelocityKmPerSecond": 47.40470463533486,
"distanceParsecs": 10
},
"output": {
"properMotionMasPerJulianYear": 1000.0000000000001
}
}Limitations and assumptions
The speed must be a transverse component under the same distance convention. Apply the exact scope and assumptions explained above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are explained above; extremely large inputs or outputs can also be rejected. Input errors differ from successful false results, empty match lists and unknown-evidence placeholders.
Alternative or Complementary methods
Use Proper Motion Tangential Velocity Calculator for a related task: Proper motion and distance together determine a tangential speed under consistent units.
Use Perspective Acceleration Effect Radial Rate Estimator for a related task: Perspective acceleration arises from changing apparent angular motion as radial distance changes.
References
Similar or alternative tools
- Proper Motion Tangential Velocity Calculator
Proper motion and distance together determine a tangential speed under consistent units.
- Perspective Acceleration Effect Radial Rate Estimator
Perspective acceleration arises from changing apparent angular motion as radial distance changes.