OBSERVER SKY VIEW
Awaiting observer dataWhere to look
Compass projection of the current sky direction. The chart shows direction, not brightness or a photograph of the sky.
NASA/JPL HORIZONS EPHEMERIS
Where Is BepiColombo Now? Live Location & Distance
ESA/JAXA · Mercury · Launched 2018-10-20
The road to Mercury
BepiColombo’s journey uses repeated planetary flybys to reshape its orbit. A Mercury flyby is different from orbit insertion. The tracker follows the available mission ephemeris, whose coverage can change between mission phases.
FROM EARTH NOWWaiting for dataSample timestamp will appear here
FROM SUN NOWWaiting for dataSample timestamp will appear here
ONE-WAY RADIO DELAY—Geometric light time to Earth
TIME SINCE LAUNCH—Launch date: 2018-10-20 · calendar-day estimate
Loading current samples independently of the map date.
Radio signal simulator
Estimate a signal’s travel time from a fixed distance sample. No signal is transmitted. Spacecraft motion, processing time and station scheduling are excluded.
An ideal immediate reply takes twice the one-way light time.
Explore mission dates
Snapshots use 12:00 UTC on the selected day, not exact encounter time. Check the map timestamp and data availability. The current summary above stays independent.
Drag to rotate · Scroll/pinch to zoom · Tap a planet to focus
Solar System ViewPlanet sizes are enlarged for visibility; orbital positions use JPL ephemerides.
Loading mission ephemeris…UTC --:--:--
BepiColombo · FROM YOUR LOCATION
Find the spacecraft in the sky
See where the spacecraft appears in the sky for the location selected above. The chart shows direction and does not guarantee naked-eye or telescope visibility.
Waiting for your selected location…
Right ascension · ICRF—
Declination · ICRF—
Sky direction—
Above horizon—
Rise, highest point and set
Rise above horizon—
Highest altitude—
Set below horizon—
Rise, highest point and set are estimates. Atmospheric refraction and terrain are excluded.
A calculated direction does not imply optical visibility.
Distance from your location
Observer range in astronomical units. Close flybys and maneuvers can change the distance quickly.
About BepiColombo
A joint ESA/JAXA mission in its Mercury arrival phase, designed to study the innermost planet.
DestinationMercury
Launched2018-10-20
AgencyESA/JAXA
DAILY SKY POSITION
12:00 UTC sample · dates and times labeled UTCThe next 15 days
| Date (UTC) | RA (°) | Dec (°) | Azimuth (°) | Altitude (°) | Range (AU) |
|---|---|---|---|---|---|
| Select your observing location above to load the position table. | |||||
These are observer-based line-of-sight calculations, independent of the compressed scale used in the 3D voyage map. No brightness prediction is made.
TRACKER GUIDE & MISSION EXPLAINER
BepiColombo Tracker: Journey to Mercury and Mission Architecture
BepiColombo is a joint ESA-JAXA mission designed to study Mercury with two scientific orbiters. The tracker above uses JPL Horizons ephemerides to show the cruise and arrival trajectory, current distance, light time and Sun-centred vector.
The mission launched on October 20, 2018 aboard an Ariane 5. Reaching Mercury is difficult because a spacecraft must lose substantial orbital energy while avoiding excessive heat. BepiColombo combined solar-electric propulsion with flybys of Earth, Venus and Mercury.
Three spacecraft travelling together
During cruise, ESA's Mercury Planetary Orbiter and JAXA's Mercury Magnetospheric Orbiter, Mio, travel with the Mercury Transfer Module. Near Mercury, the stack separates and the two science orbiters enter complementary polar orbits.
MPO will investigate Mercury's surface, composition, interior and surrounding environment. Mio concentrates on the planet's magnetic field and magnetosphere. Together they can distinguish spatial changes from time-dependent variations more effectively than one spacecraft.
How the tracker should be read
Horizons provides position and velocity vectors for the mission identifier. SpaceTracker.live samples and interpolates those ephemerides. During gravity assists and arrival operations, the true mission geometry is complex; the compressed scene is only a guide.
A change in Earth distance can be caused by both the spacecraft path and Earth's own motion. Sun distance is especially important near Mercury because solar radiation and thermal design shape operations.
Educational questions
- Why is slowing down toward Mercury harder than simply falling toward the Sun?
- How do gravity assists change velocity without consuming equivalent propellant?
- Why are two orbiters better for studying a changing magnetosphere?
- How does solar-electric propulsion differ from a short chemical-engine burn?
- Why must the visual compress interplanetary distances?
Accuracy and status
ESA listed Mercury arrival activities for late 2026 with a sequence of manoeuvres continuing into 2027. Mission schedules can be updated, so official ESA pages should be used for operational milestones. The tracker is limited to ephemeris position and does not report spacecraft health or separation events.
Mercury as an engineering destination
Mercury combines intense sunlight with long cold nights, a weak magnetic field and an orbit deep inside the Sun's gravity well. BepiColombo must manage thermal exposure during cruise and science operations while carrying two observatories with different goals. The tracker gives a geometric context for that engineering problem: Sun distance affects heating and power, Earth distance affects communications, and arrival velocity determines how difficult capture will be. Following these quantities through the approach is more informative than treating the mission as a straight line from Earth to Mercury.
MISSION REFERENCE · RESEARCH & TRAJECTORY
BepiColombo science, Mercury approach and mission interpretation
Two orbiters and a long cruise
BepiColombo carries ESA’s Mercury Planetary Orbiter and JAXA’s Mercury Magnetospheric Orbiter, known as Mio, toward Mercury. During the interplanetary cruise they travel in a combined stack with a transfer module; the two science spacecraft will later pursue different observing roles. Mercury is deep in the Sun’s gravity well. Reaching orbit there requires shedding much of the sideways orbital energy inherited from Earth, so the mission uses solar-electric propulsion and repeated planetary gravity assists rather than a simple straight flight.
What the spacecraft will investigate
The ESA orbiter is designed to study Mercury’s surface, composition, geology and internal structure. Mio focuses strongly on the planet’s magnetic environment and interactions with the solar wind. Taken together, those measurements can connect what Mercury is made of with how it responds to intense solar conditions. A mission tracker shows the cruise or operating geometry; it cannot substitute for a scientific image, a magnetometer reading or a finding released by the science teams.
Why flyby dates and arrival estimates can change
A Mercury flyby alters the trajectory that sets up the next encounter. Engineers also account for propulsion performance, navigation updates and spacecraft constraints. Published future milestones are plans, not observations that have already happened. This article therefore distinguishes completed events from planned operations and directs readers to ESA for the current schedule. A graph of spacecraft distance from Earth can rise even when the vehicle is successfully approaching Mercury, since Earth and Mercury keep moving around the Sun.
Reading a Mercury-bound trajectory
The map uses a compressed Solar System scale; it does not mean the mission craft is the visual size shown near a planet. Earth-to-spacecraft distance is relevant to communication delay. Sun-to-spacecraft distance helps put heat and illumination into context. Neither alone measures distance to Mercury. A location-based sky chart gives the direction of the spacecraft from an observer, not a promise that a distant, faint spacecraft can be visually found.
Frequently asked questions
Why does BepiColombo need so many flybys?
Mercury is deep in the Sun's gravity well. Flybys and electric propulsion remove orbital energy gradually and manage arrival speed.
Is BepiColombo one spacecraft?
The cruise stack contains a transfer module and two science orbiters that will separate for Mercury operations.
What will the two orbiters study?
MPO focuses on the planet and its environment; JAXA's Mio focuses strongly on the magnetosphere and solar-wind interaction.
Does this tracker show official arrival manoeuvres?
No. It displays ephemeris-derived position. Use ESA operations updates for manoeuvre status.
Sources and further reading
Educational-use note: SpaceTracker.live is an independent educational website and is not an official mission-control service. Positions, paths, distances and pass predictions are computed from third-party orbital elements or ephemerides. They may be delayed or approximate and must not be used for navigation, collision avoidance or safety-critical decisions.