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Asteroid Near-Earth

2015 SY

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(2015 SY)

Where is it now

Distance from Sun
0.968 AU
True anomaly
235.43°
Distance from Earth
1.172 AU
As of
21 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 — 0.995 AU from the Sun Earth 2015 SY — 0.968 AU from the Sun 2015 SY
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2015 SY is 1.172 AU from Earth today (9.7 light-minutes).

In the sky

Right ascension
10h 29m 59s
Declination
+06° 38′ 58″
Constellation
Leo
Distance from Earth
1.17 AU
Elongation from the Sun
52.17° — near the Sun — look low at dusk or dawn

Visible from both hemispheres.

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
0.919 AU
Eccentricity
0.487
Inclination
3.17°
Orbital period
321.6 days
Perihelion
0.471 AU
Aphelion
1.366 AU
Longitude of ascending node
182.56°
Argument of periapsis
43.59°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 3.0 LD
0.0077 AU
Tisserand (Jupiter)
6.397

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
137
Data arc
9.22 years
First observed
20 September 2015
Last observed
7 December 2024
Residual RMS
0.38 ″
Solution · Otto Matic
7 December 2024

Physical properties

Rotation period
2.1 hours

Visual & observation

Absolute magnitude (H)
23.42

Discovery & classification

Aten Near-Earth Object

Close approaches 163 on record

When (UTC) Body Distance Lunar distances Relative speed
2029-08-20 17:21:00 Merc 0.0956 AU 37.2 LD 20.7 km/s
2029-08-20 17:21:00 Mercury 0.0956 AU 37.2 LD 20.7 km/s
2031-04-13 23:11:00 Venus 0.1133 AU 44.1 LD 21.8 km/s
2032-04-07 22:00:00 Merc 0.0509 AU 19.8 LD 15.7 km/s
2032-04-07 22:00:00 Mercury 0.0509 AU 19.8 LD 15.7 km/s
2034-11-23 05:03:00 Merc 0.0283 AU 11.0 LD 16.1 km/s
2034-11-23 05:03:00 Mercury 0.0283 AU 11.0 LD 16.1 km/s
2037-06-11 11:42:00 Venus 0.0669 AU 26.0 LD 18 km/s
2037-07-13 07:00:00 Merc 0.0839 AU 32.7 LD 22 km/s
2037-07-13 07:00:00 Mercury 0.0839 AU 32.7 LD 22 km/s

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

Sources