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Asteroid Near-Earth

2017 SE20

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(2017 SE20)

Where is it now

Distance from Sun
0.832 AU
True anomaly
125.92°
Distance from Earth
0.931 AU
As of
16 October 2026

Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.

Sun Earth — 0.997 AU from the Sun Earth 2017 SE20 — 0.832 AU from the Sun 2017 SE20
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2017 SE20 is 0.931 AU from Earth today (7.7 light-minutes).

In the sky

Right ascension
16h 50m 54s
Declination
-26° 50′ 14″
Constellation
Scorpius
Distance from Earth
0.93 AU
Elongation from the Sun
51.1° — near the Sun — look low at dusk or dawn

Favours the southern hemisphere; low or below the horizon from far north.

From your location

See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.

How do I find my coordinates?

Google Maps on a computer

  1. Right-click the spot where you'll be observing.
  2. The first line of the menu is the coordinates, e.g. 51.50722, -0.12758 — click it and they're copied.
  3. Paste them above.

Google Maps on a phone

  1. Press and hold the spot to drop a pin.
  2. The coordinates appear in the search bar (or on the pin's card) — tap to copy, then paste above.

A full Google Maps link works too, but the short maps.app.goo.gl share links don't carry coordinates — copy the numbers instead. We round to about a kilometre; that's all the sky calculation needs.

Know your what3words address? Paste it, e.g. ///filled.count.soap. This is optional — the three words are sent to what3words to convert them, and we don't store the address or the result.

Your location stays in your browser and is sent only for this calculation. Using a what3words address is optional; if you do, the three words go to what3words to be converted and we don't record them. Set a location first, then you can save an email alert for this object. See our privacy policy.

Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.

Orbital elements

Semi-major axis
0.755 AU
Eccentricity
0.3706
Inclination
7.31°
Orbital period
239.4 days
Perihelion
0.475 AU
Aphelion
1.034 AU
Longitude of ascending node
4.51°
Argument of periapsis
192.45°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 4.2 LD
0.0107 AU
Tisserand (Jupiter)
7.598

Orbit quality

Orbit poorly determined (uncertainty code 7).

Observations used
23
Data arc
4 days
First observed
26 September 2017
Last observed
30 September 2017
Residual RMS
0.48 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
27.9

Discovery & classification

Aten Near-Earth Object

Close approaches 64 on record

Flyby geometry
Ecliptic flyby of 2017 SE20 at 2032-09-23 05:21 UTC Top-down view of the ecliptic, Earth at the centre, for the 2032-09-23 05:21 UTC close approach of 2017 SE20. Catalogue miss distance 147.3 LD · 5.66 × 10⁷ km. The curve is the geocentric path from 2032-09-20 to 2032-09-26, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 147.3 LD · 5.66 × 10⁷ km 2032-09-23 05:21 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2032-09-23 05:21 UTC close approach of 2017 SE20. Catalogue miss distance 147.3 LD · 5.66 × 10⁷ km. The curve is the geocentric path from 2032-09-20 to 2032-09-26, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.

JPL Horizons

When (UTC) Body Distance Lunar distances Relative speed
2032-09-23 05:21:00 Earth 0.3786 AU 147.3 LD 20.4 km/s
2034-09-18 01:12:00 Earth 0.1915 AU 74.5 LD 14.2 km/s
2035-04-12 04:35:00 Venus 0.0614 AU 23.9 LD 11.9 km/s
2040-11-04 07:13:00 Earth 0.1505 AU 58.6 LD 11.6 km/s
2042-06-10 21:32:00 Earth 0.4627 AU 180.1 LD 13.7 km/s
2042-11-01 04:43:00 Earth 0.3157 AU 122.9 LD 17.6 km/s
2042-12-03 20:11:00 Venus 0.0846 AU 32.9 LD 12 km/s
2044-10-24 22:35:00 Earth 0.4904 AU 190.9 LD 23.7 km/s
2045-01-11 16:19:00 Merc 0.0888 AU 34.6 LD 14.7 km/s
2045-01-11 16:19:00 Mercury 0.0888 AU 34.6 LD 14.7 km/s

Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.

Sources