|
C/2017 E1 (Borisov) |
| ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
| Nearest approach | 18 Mar 2017 | 11.5 | 0.995 AU | 1.331 AU | 20h42m | -08°22' | 48.0° | 48.1° | 263° |
| Perihelion | 10 Apr 2017 | 10.9 | 0.908 AU | 1.417 AU | 22h43m | -03°31' | 39.6° | 44.7° | 253° |
| Today | 25 Nov 2025 | 43.1 | 22.976 AU | 22.141 AU | 06h16m | +11°44' | 147.0° | 1.3° | 290° |
C/2017 E1 (Borisov)- 2025-11-25
astro.vanbuitenen.nl
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 10.9 + 5 log[∆] + 18.7 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 C/2017 E1 (Borisov) are:
e (Eccentricity) : 1.0032610
q (Perihelion distance) : 0.9078320
i (Inclination) : 14.57020
Ω (Longitude of ascending node) : 142.57660
ω (Argument of perihelion) : 152.79570
L (Longitude of perihelion) : 116.12653
B (Latitude of perihelion) : 6.60403
T (Time of perihelion passage) : 2457853.85400
Epoch : 2022 May 26
Reference : MPC106346
Classification(s): : Nearly isotropic; New (a > 10000 AU)
Ephemerides
Date Time RA (2000) DEC (2000) delta radius elong phase PA magn
2025-11-24 00:00 UT 06 17 02.7 +11 44 49 22.147 22.968 145.5 1.4 289 43.1
2025-11-25 00:00 UT 06 16 53.8 +11 44 38 22.143 22.973 146.5 1.4 290 43.1
2025-11-25 11:23 UT 06 16 49.5 +11 44 32 22.141 22.976 147.0 1.3 290 43.1
2025-11-26 00:00 UT 06 16 44.8 +11 44 27 22.139 22.979 147.5 1.3 291 43.1
2025-11-27 00:00 UT 06 16 35.7 +11 44 17 22.136 22.984 148.5 1.3 291 43.1
2025-11-28 00:00 UT 06 16 26.5 +11 44 07 22.133 22.989 149.4 1.3 292 43.1
2025-11-29 00:00 UT 06 16 17.2 +11 43 58 22.130 22.994 150.4 1.2 293 43.1
2025-11-30 00:00 UT 06 16 07.8 +11 43 49 22.128 22.999 151.3 1.2 294 43.1
2025-12-01 00:00 UT 06 15 58.4 +11 43 41 22.126 23.004 152.3 1.1 295 43.1
2025-12-02 00:00 UT 06 15 48.8 +11 43 33 22.124 23.009 153.2 1.1 296 43.1
2025-12-03 00:00 UT 06 15 39.2 +11 43 26 22.122 23.014 154.2 1.1 297 43.1
2025-12-04 00:00 UT 06 15 29.5 +11 43 20 22.121 23.019 155.1 1.0 298 43.1
2025-12-05 00:00 UT 06 15 19.8 +11 43 14 22.120 23.024 156.0 1.0 299 43.1
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.
