174P/Echeclus
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	19 Apr 2015	12.7	5.867 AU	6.533 AU	22h58m	-05°21'	45.0°	7.0°	249°
Nearest approach	9 Sep 2015	12.1	5.906 AU	4.900 AU	23h19m	-03°53'	177.0°	0.5°	239°
Today	28 Dec 2025	23.6	13.856 AU	12.995 AU	08h31m	+15°16'	150.0°	2.0°	290°

The interactive orbit chart above shows the comet's path through the solar system and its position at the given date. Green and blue lines are shown perpendicular to the ecliptic plane: Green if the path is above the ecliptic plane, blue if it is below. (Left-click and drag to rotate the view; Right-click and drag to move the view; Use scroll wheel to zoom in our out.)

Light curve

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations from COBS. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently -11.0 + 5 log[∆] + 25.4 log[r]). An additional green curve is displayed when an increase in apparent brightness is expected due to forward scattering of sunlight, which occurs when a dust-rich comet is located between the Earth and the Sun. (See Marcus 2007)

Charts

The all-sky chart below shows the path of the comet over the same period as the light curve. The comet's current position is marked yellow.

The following chart shows the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Orbital elements

The orbital elements of 174P/Echeclus are:

    e (Eccentricity)                : 0.4547310
    q (Perihelion distance)         : 5.8665610
    i (Inclination)                 : 4.34070
    Ω (Longitude of ascending node) : 173.34250
    ω (Argument of perihelion)      : 163.42610
    L (Longitude of perihelion)     : 156.81354
    B (Latitude of perihelion)      : 1.23710
    T (Time of perihelion passage)  : 2457131.87730
    P (Orbital period in years)     : 35.29

    Epoch                           : 2025 Jul 29
    Reference                       : MPC 92985

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); Halley type (P < 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-27 00:00 UT   08 32 15.2   +15 15 03    13.006   13.853  148.4    2.1   290   23.6 
2025-12-28 00:00 UT   08 32 03.0   +15 15 43    12.999   13.855  149.4    2.1   290   23.6 
2025-12-28 13:34 UT   08 31 55.9   +15 16 05    12.995   13.856  150.0    2.0   290   23.6 
2025-12-29 00:00 UT   08 31 50.5   +15 16 23    12.992   13.856  150.5    2.0   290   23.6 
2025-12-30 00:00 UT   08 31 37.9   +15 17 04    12.985   13.858  151.5    1.9   291   23.6 
2025-12-31 00:00 UT   08 31 25.1   +15 17 45    12.978   13.859  152.6    1.9   291   23.6 
2026-01-01 00:00 UT   08 31 12.2   +15 18 28    12.972   13.860  153.7    1.8   291   23.6 
2026-01-02 00:00 UT   08 30 59.1   +15 19 11    12.966   13.862  154.7    1.7   292   23.6 
2026-01-03 00:00 UT   08 30 45.9   +15 19 55    12.960   13.863  155.8    1.7   292   23.6 
2026-01-04 00:00 UT   08 30 32.5   +15 20 40    12.955   13.865  156.9    1.6   292   23.6 
2026-01-05 00:00 UT   08 30 19.0   +15 21 25    12.950   13.866  157.9    1.5   293   23.6 
2026-01-06 00:00 UT   08 30 05.4   +15 22 11    12.945   13.868  159.0    1.5   293   23.6 
2026-01-07 00:00 UT   08 29 51.7   +15 22 58    12.941   13.869  160.0    1.4   294   23.6 

    Terminology:
            
    delta:  distance between comet and earth in AU
    radius: distance between comet and sun in AU
    magn:   magnitude (brightness) estimate    
    ra:     right ascension in hours (24h = 360deg)
    dec:    declination in degrees
    elong:  elongation in degrees (angle sun-earth-comet)    
    phase:  phase angle in degrees (angle sun-comet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km      
    

Orbital elements usually provided by the MPC (Minor Planet Center).
Observations contributed by observers worldwide, via COBS (Comet Observation Database) or the MPC (Minor Planet Center)
Calculations by a modified version of AAPlus, a C# implementation of the AA+ project by PJ Naughter from the algorithms presented in the book "Astronomical Algorithms" by Jean Meeus.
NGC2000 dso catalog and star labels from VizieR as provided by the Strasbourg astronomical Data Center.
Tycho2 catalog from the ESO archive.