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A Complete Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 7:54  
clear_day Transit: 11:51  
SunsetSet: 15:49 south
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Dwarf Planets and Asteroids » 

Asteroid 5 Astraea

Altitude: 52.9°   Azimuth: 159.4°   Direction: South-South-East

5 Astraea is a relatively small main-belt asteroid located between the orbits of Mars and Jupiter. It was discovered 8 December 1845 by German astronomer Karl Ludwig Hencke and is named after the Greek goddess of justice. Astraea has a diameter of approximately 119 kilometers and is irregularly shaped, with a rotation period of about 16 hours. Its surface is covered in numerous impact craters, some of which are several kilometers in diameter. Astraea's composition is thought to be a mixture of rock and metal, similar to the composition of the Earth's crust. It has a relatively low density compared to other asteroids, indicating that it may have a porous interior. Astraea orbits the Sun once every 4.14 Earth years and has been observed by ground-based telescopes, which have revealed insights into its geology, composition, and history.

Asteroid 5 Astraea is currently in the constellation of Gemini.

The current Right Ascension of Asteroid 5 Astraea is 06h 38m 28s and the Declination is +15° 50’ 26” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current magnitude of Asteroid 5 Astraea is 9.90 (JPL).

06h 38m 28s
+15° 50’ 26”

Today's rise, transit and set times of Asteroid 5 Astraea from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

Azimuth: 74.1°
Max altitude: 54.4°
Azimuth: 285.8°
  • 5 Astraea is above the horizon from Greenwich, United Kingdom edit_location_alt.
  • Right now it is placed in the South-South-East direction at an altitude of 53° above the horizon.
  • Given its current magnitude, 5 Astraea is visible with the help of a binocular with a 60mm aperture, might require a small telescope.
  • 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.

Available Resources

Asteroid 5 Astraea Position and Finder Charts

Below we provide Asteroid 5 Astraea 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.

Finder chart of 5 Astraea in Gemini on December,11 2023
Map showing Asteroid 5 Astraea in Gemini on December, 11 2023
Field of view: 50x30 degrees
View fullscreen
Finder chart of 5 Astraea
Map showing Asteroid 5 Astraea in Gemini on December, 11 2023
Field of view: 10x6 degrees
View fullscreen

Higher precision deep sky finder chart, 60 arcmin wide, showing where Asteroid 5 Astraea is right now. Click on the image to see a more detailed fullscreen tracker view.

5 Astraea
RA: 06h 38m 28s
Dec: +15° 50’ 26”
Deep sky finder chart for Asteroid 5 Astraea
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Asteroid 5 Astraea?, a page that provides all the information needed to find Asteroid 5 Astraea in the sky and additional links to sky charts.

Asteroid 5 Astraea Distance from Earth

The distance of Asteroid 5 Astraea from Earth is currently 191,241,344 kilometers, equivalent to 1.278369 Astronomical Units. Light takes 10 minutes and 37.9125 seconds to travel from Asteroid 5 Astraea and arrive to us.

10 minutes and 37.9125 seconds

The following chart shows the distance of Asteroid 5 Astraea 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.

Chart of the distance of Asteroid 5 Astraea from Earth in Astronomical Units (au)

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 5 Astraea from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach of Asteroid 5 Astraea to Earth

Between 1 January 1900 and 31 December 2099, the closest approach of Asteroid 5 Astraea to Earth happens on Fri Feb 13 1925 at a distance of 1.093100 Astronomical Units, or 163,525,365 kilometers:

Fri Feb 13 1925

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

Asteroid 5 Astraea Brightness and Light Curve

The following chart is the predicted light curve (visual magnitude as a function of time) of Asteroid 5 Astraea, 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.

Chart of the magnitude of Asteroid 5 Astraea as a function of time

Asteroid 5 Astraea Orbital Elements

The following table lists the orbital elements of Asteroid 5 Astraea at epoch 24 February 2023 00:00 UTC (JD: 2460000.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.18792368
Orbit inclination i 5.36012857°
Perihelion distance q 2.09409950 AU
313,272,827 km
Aphelion distance Q 3.06329633 AU
458,262,609 km
Semi-major axis a 2.57869792 AU
385,767,718 km
Orbital period period 4.1410 years
1,512.5131 days
Date of perihelion transit Tp 2024-May-06 19:49:09
2,460,437.3258 JD
Argument of perihelion peri 358.88655645318°
Longitude of the ascending node node 141.52276093715°
Mean anomaly M 256.0291368156°
Mean motion n 0.23801448°/day

Visualization of Asteroid 5 Astraea Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Asteroid 5 Astraea with respect of the Sun and the orbits of the major planets. The position of Asteroid 5 Astraea 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 5 Astraea
View Asteroid 5 Astraea in the 3D Solar System Simulator

Asteroid 5 Astraea Physical Data

The following shows the known values of the most important physical parameters of Asteroid 5 Astraea. Source: JPL Small-Body Database

Physical Parameter Value Relative to Earth
Diameter 119.07 km 0.0093
Sideral Rotation 16.8000 hours 0.7019
Absolute Magnitude 6.85
Geometric Albedo 0.2268

Asteroid 5 Astraea 15 Days Ephemeris

The following table lists the ephemerides of Asteroid 5 Astraea computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Asteroid 5 Astraea in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2023 Dec 04 06h 43m 06s +15° 46’ 09” 10.11 Gemini
2023 Dec 05 06h 42m 33s +15° 46’ 27” 10.08 Gemini
2023 Dec 06 06h 41m 56s +15° 46’ 51” 10.05 Gemini
2023 Dec 07 06h 41m 17s +15° 47’ 22” 10.02 Gemini
2023 Dec 08 06h 40m 39s +15° 48’ 00” 9.99 Gemini
2023 Dec 09 06h 39m 56s +15° 48’ 42” 9.96 Gemini
2023 Dec 10 06h 39m 14s +15° 49’ 32” 9.93 Gemini
2023 Dec 11 06h 38m 29s +15° 50’ 29” 9.90 Gemini
2023 Dec 12 06h 37m 42s +15° 51’ 30” 9.87 Gemini
2023 Dec 13 06h 36m 55s +15° 52’ 40” 9.84 Gemini
2023 Dec 14 06h 36m 06s +15° 53’ 56” 9.81 Gemini
2023 Dec 15 06h 35m 16s +15° 55’ 17” 9.78 Gemini
2023 Dec 16 06h 34m 23s +15° 56’ 44” 9.75 Gemini
2023 Dec 17 06h 33m 32s +15° 58’ 18” 9.72 Gemini