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Asteroid 1999 KW4

Asteroid 1999 KW4 is currently in the constellation of Eridanus. The current Right Ascension of Asteroid 1999 KW4 is 04h 50m 28s and the Declination is -06° 57’ 53” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current magnitude of Asteroid 1999 KW4 is 19.00 (JPL).

Summary of key facts about Asteroid 1999 KW4 [tip: you can also create a Quick Access page for this data if you access it frequently and would like to have a simpler view]:

04h 50m 28s
-06° 57’ 53”
  • 1999 WK4 is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the South-South-West direction at an altitude of 28° above the horizon.
  • Given its current magnitude, 1999 WK4 is visible only through long exposure photography.
  • See also 1999 WK4 rise and set times.
  • Go to interactive sky chart

If you need to access this information frequently for your observations, you can create a simple customized Quick Access page, so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.

Additional information about Asteroid 1999 KW4 available on TheSkyLive:

Available Resources

Asteroid 1999 KW4 Position and Finder Charts

Below we provide Asteroid 1999 KW4 finder charts showing where the object is right now in the sky with respect to the brightest stars. The first finder chart has a field of view of 50 degrees, while the second one has a field of view of 10 degrees. Click on each finder chart to access a full screen interactive Online Planetarium.

Map showing Asteroid 1999 KW4 in Eridanus on May, 12 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Asteroid 1999 KW4 in Eridanus on May, 12 2021
Field of view: 10x6 degrees
View fullscreen
 = visible to the naked eye
 = binocular, brighter than 10th magnitude
= current altitude ≥ 30°   = current altitude < 30°   = below the horizon
Location: Greenwich, United Kingdom [change]

Higher precision deep sky finder chart, 60 arcmin wide, showing where Asteroid 1999 KW4 is right now. Click on the image to see a more detailed fullscreen tracker view.

1999 WK4
RA: 04h 50m 28s
Dec: -06° 57’ 53”
Deep sky finder chart for Asteroid 1999 KW4
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Asteroid 1999 KW4?, a page that provides all the information needed to find Asteroid 1999 KW4 in the sky and additional links to sky charts.

Asteroid 1999 KW4 Distance from Earth

The distance of Asteroid 1999 KW4 from Earth is currently 65,128,208 kilometers, equivalent to 0.435355 Astronomical Units. Light takes 3 minutes and 37.2443 seconds to travel from Asteroid 1999 KW4 and arrive to us.

3 minutes and 37.2443 seconds

The following chart shows the distance of Asteroid 1999 KW4 from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.

Distance of Asteroid 1999 KW4 from Earth between January 2013 and December 2100

The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of 1999 WK4 from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Asteroid 1999 KW4 to Earth

Between January 2013 and December 2100, the closest approach of Asteroid 1999 KW4 to Earth happens on Mon May 26 2036 at a distance of 0.016364 Astronomical Units, or 2,447,983 kilometers:

Mon May 26 2036

NOTE: values for the closest approach are computed with a sampling interval of 1 day.

Asteroid 1999 KW4 brightness

The current visual magnitude of Asteroid 1999 KW4 is 19.00.


The following chart is the predicted light curve (visual magnitude as a function of time) of Asteroid 1999 KW4, according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.

Predicted magnitude of Asteroid 1999 KW4 between January 2013 and December 2100

Asteroid 1999 KW4 rise and set times

Location: Greenwich, United Kingdom [change]
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

Today's Asteroid 1999 KW4 rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 96.9°
Max altitude: 31.6°
Azimuth: 263.0°

The rise and set times are defined as the time at which the upper limb of Asteroid 1999 KW4 touches the horizon, considering the effect of the atmospheric refraction. As the atmospheric conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.

Asteroid 1999 KW4 Orbital Elements

The following table lists the orbital elements of Asteroid 1999 KW4 at epoch 16 December 2020 00:00 UTC (JD: 2459200.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.68839503
Orbit inclination i 38.88220171°
Perihelion distance q 0.20015828 AU
29,943,253 km
Aphelion distance Q 1.08453418 AU
162,244,005 km
Semi-major axis a 0.64234623 AU
96,093,629 km
Orbital period period 0.5100 years
188.0408 days
Date of perihelion transit Tp 2020-Oct-06 13:03:02
2,459,129.0438 JD
Next perihelion transit 2021-Apr-12 14:01
2,459,317.0846 JD
Argument of perihelion peri 192.64377652767°
Longitude of the ascending node node 244.90319233525°
Mean anomaly M 136.80134186625°
Mean motion n 1.91447766°/day

Visualization of Asteroid 1999 KW4 Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Asteroid 1999 KW4 with respect of the Sun and the orbits of the major planets. The position of Asteroid 1999 KW4 and the planets along their orbits in this diagram accurately represents the current configuration of the objects in the Solar System. This is an experimental feature and it requires a WebGL enabled browser. Please provide us feedback!

Orbit Diagram of Asteroid 1999 KW4
View Asteroid 1999 KW4 in the 3D Solar System Simulator

Asteroid 1999 KW4 15 Days Ephemeris

The following table lists the ephemerides of Asteroid 1999 KW4 computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Asteroid 1999 KW4 in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2021 May 05 04h 04m 00s -04° 40’ 05” 19.00 Eridanus
2021 May 06 04h 09m 19s -05° 02’ 41” 19.00 Eridanus
2021 May 07 04h 14m 48s -05° 23’ 57” 19.00 Eridanus
2021 May 08 04h 20m 30s -05° 43’ 53” 19.00 Eridanus
2021 May 09 04h 26m 29s -06° 02’ 26” 19.00 Eridanus
2021 May 10 04h 32m 41s -06° 19’ 35” 19.00 Eridanus
2021 May 11 04h 39m 11s -06° 35’ 17” 19.00 Eridanus
2021 May 12 04h 46m 00s -06° 49’ 30” 19.00 Eridanus
2021 May 13 04h 53m 09s -07° 02’ 09” 19.00 Eridanus
2021 May 14 05h 00m 38s -07° 13’ 10” 19.00 Eridanus
2021 May 15 05h 08m 30s -07° 22’ 28” 19.00 Eridanus
2021 May 16 05h 16m 45s -07° 29’ 57” 19.00 Orion
2021 May 17 05h 25m 23s -07° 35’ 30” 19.00 Orion
2021 May 18 05h 34m 26s -07° 39’ 00” 19.00 Orion