Planetary Opposition 2025: Best Time to See Planets
The next planet to reach opposition will be Mars — mark your calendar for January 16, 2025. With the Sky Tonight app, you can easily find reddish Mars in your location. Read this article to learn more about oppositions and find out the best dates to see planets and asteroids.
Contents
- What does opposition mean in astronomy?
- Planetary oppositions
- Upcoming planetary oppositions
- Other upcoming oppositions
- F.A.Q.
- Planet oppositions: Bottom line
What does opposition mean in astronomy?
Astronomical opposition means that a planet is located on the opposite side of the Earth from the Sun. From our perspective, it means a planet at opposition is precisely 180 degrees from the Sun in the sky — so, when the Sun sets in the west, a planet appears in the east. In addition to planets, an opposition can be reached by comets, asteroids, and some other Solar System objects. A well-known example of opposition is a Full Moon. During this event, the lunar disk is opposed to the Sun, therefore fully lit by the star’s light.
Planetary oppositions
Next opposition: Mars (January 16, 2025)
Mars will reach opposition on January 16 at 01:17 GMT (January 15, at 8:17 p.m. ET). For a few weeks around opposition, Mars will look big and bright in the sky. The planet will be in the constellation Gemini, visible in the evening and during the night. To find Mars in the sky in your location, use the free Sky Tonight app.
What planets can be seen at opposition from the Earth?
Since an opposition can only occur when the Earth is between the Sun and another celestial body, this event happens for the planets further from the Sun than the Earth. These are Mars, Jupiter, Saturn, Uranus, and Neptune.
The planets’ oppositions occur roughly every year when the Earth reaches the proper configuration with them relative to the Sun. The only exception here is Mars. The Red Planet’s orbit and orbital speed are similar to the Earth’s, so the Earth “outraces” Mars only about every 27 months. That’s why Mars oppositions occur only once in about two-three years. Mercury and Venus are located inside the Earth’s orbit, so we’ll never see them at opposition.
How to find a planet at opposition?
To find a planet at opposition, look in the opposite direction from the sunset. The planet will be well-placed for a few weeks around the exact moment of opposition. So, check a forecast for your location, find a date close to the opposition when the skies are clear, and get outside to observe the bright planet.
You can easily locate and identify a planet using a stargazing app like Sky Tonight:
- To locate your desired planet, use the app's search function. Tap the magnifier icon in the bottom-left corner of the main screen and type the object’s name in the search bar. Tap the blue target button next to the matching result, and then tap the blue compass button in the lower right corner of the screen. Move your device in the direction of the white arrow until you see the planet on the screen. This is the direction in which you will find the planet in the real sky above you.
- To identify any bright dot in the sky, launch the app and point your device at the sky. On the app’s interactive sky map, you’ll see what celestial objects are in that direction. You can tap the object to learn its name and tap its name for more information.
At opposition, you can spot most of the planets with the naked eye, but you’ll see them even better through a pair of binoculars or a telescope. For instance, with a small 4-inch telescope, you should be able to observe Saturn’s rings, including the Cassini Division between them.
Why are planetary oppositions interesting?
Opposition is the best time to observe a planet or another celestial body. At that time, objects are fully illuminated by the Sun and shine brightly in the sky. Moreover, planetary oppositions occur near a planet’s closest approach to the Earth, when a planet appears at its biggest. Mars experiences the most striking size change because it’s the closest superior planet to the Earth. Most importantly, an opposition gives us plenty of time for stargazing! A celestial object is seen through the night and well-placed in the midnight sky. It is no coincidence that asteroids and other faint Solar System objects are often discovered at their opposition.
Upcoming planetary oppositions
The complete calendar of all the planetary and other celestial events is available in the stargazing app Sky Tonight.
January 16, 2025: Mars opposition
Mars will reach opposition on January 16, 2025, at 01:17 GMT (January 15, 2025, at 8:17 p.m. ET). This is the most anticipated planetary opposition of all, as Mars oppositions occur only once in 2–3 years. Other planets that can be in opposition (Jupiter, Saturn, Uranus, and Neptune) reach it about every year.
During the opposition, Mars will shine with a magnitude of -1.4 in the constellation Gemini. It will be easily visible to the naked eye. To explore the planet's surface, such as ice caps and brighter and darker areas, use a telescope of at least 50x magnification.
The planet will be in the sky throughout the night, reaching its highest point around midnight. In addition to Mars, you may spot 5 other planets if you start watching at sunset. This is commonly called a planetary parade – you can learn more about it in our dedicated article. To complete the view, the brightest Gemini star Pollux will be shining close to Mars.
Other upcoming oppositions
Not only planets but also comets, asteroids, and other Solar System bodies can reach opposition. Such events are more challenging to spot, so they are more for experienced astronomers. Opposition is also the best time for asteroid hunters. If you want to discover a new asteroid, it’s better to look at night in the direction opposite to the Sun, and maybe you’ll get lucky!
Asteroids in opposition
- January 13, 2025: 79 Eurynome (mag 10.2), constellation Canis Minor.
- January 14, 2025: 51 Nemausa (mag 10.6), constellation Canis Minor.
- January 31, 2025: 28 Bellona (mag 10.0), constellation Cancer.
- February 12, 2025: 29 Amphitrite (mag 9.2), constellation Leo.
- March 12, 2025: 8 Flora (mag 9.7), constellation Leo.
- March 24, 2025: 18 Melpomene (mag 10.1), constellation Virgo.
- May 1, 2025: 4 Vesta (mag 5.7), constellation Libra.
- May 8, 2025: 9 Metis (mag 9.7), constellation Libra.
- May 14, 2025: 3 Juno (mag 10.1), constellation Serpens Caput.
- May 19, 2025: 354 Eleonora (mag 10.3), constellation Hercules.
- June 5, 2025: 5 Astraea (mag 10.6), constellation Ophiuchus.
- August 2, 2025: 63 Ausonia (mag 8.6), constellation Capricornus.
- August 5, 2025: 129 Antigone (mag 10.0), constellation Capricornus.
- August 6, 2025: 532 Herculina (mag 10.2), constellation Capricornus.
- August 7, 2025: 2 Pallas (mag 9.4), constellation Delphinus.
- August 10, 2025: 89 Julia (mag 8.5), constellation Aquarius.
- August 26, 2025: 6 Hebe (mag 7.6), constellation Aquarius.
- November 5, 2025: 12 Victoria (mag 9.9), constellation Aries.
- December 7, 2025: 16 Psyche (mag 9.7), constellation Taurus.
- December 25, 2025: 42 Isis (mag 11.3), constellation Gemini.
Dwarf planets in opposition
- March 6, 2025: 90482 Orcus (mag 19.0), constellation Sextans.
- March 30, 2025: 136472 Makemake (mag 17.1), constellation Coma Berenices.
- April 21, 2025: 136108 Haumea (mag 17.2), constellation Bootes.
- July 1, 2025: 50000 Quaoar (mag 18.7), constellation Scutum.
- July 10, 2025: 2002 MS4 (mag 20.3), constellation Aquila.
- July 24, 2025: 134340 Pluto (mag 15.0), constellation Capricornus.
- August 28, 2025: 225088 Gonggong (mag 21.4), constellation Aquarius.
- October 2, 2025: 1 Ceres (mag 7.6), constellation Cetus.
F.A.Q.
What planets are in opposition now?
Jupiter reached its maximum angular size (47") and apparent brightness (mag -2.8) during the opposition on December 7, 2024. The planet will look big and bright in the sky until mid-January 2025. You can find it in the constellation Taurus.
How often do planetary oppositions occur?
A planetary opposition occurs when the Earth passes between the Sun and a planet. It happens every year for the superior planets. The only exception is the Martian opposition. Since the planet is very close to the Earth and its orbit and orbital speed are similar to the Earth’s, our planet manages to pass between Mars and the Sun only every 27 months, so we get one Martian opposition in about two-three years.
How long does an opposition last?
A planet is said to be “at opposition” at the exact moment of time, but the period of opposition lasts for a few weeks. You can observe the planet on any convenient date around that time. It will rise on the opposite side to the Sun right after sunset, reach the highest point at midnight, and set at dawn.
What is the opposite of opposition in astronomy?
The opposite of opposition in astronomy is a conjunction. During the conjunction of a planet and the Sun, the planet is at the closest distance from the Sun in the sky. It’s the most difficult time to observe the planet because the Sun hinders the view. But there are other astronomical conjunctions that don’t involve the Sun: for instance, planetary conjunctions and lunar-planetary conjunctions. They are quite interesting to observe!
Planet oppositions: Bottom line
Opposition is the best time to observe planets because they appear at their biggest and brightest and are visible all night through. Don’t miss the opposition of Mars on January 16, 2025! Get the stargazing app Sky Tonight to easily find Mars or any other planet in the sky in your location.
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