Planet Data For January

The table below shows key data for the planets this month, including rise, transit and set times, as well as magnitude, apparent size and position data (right ascension and declination).

Events that occur when the sun is below the horizon are shown with a black background and white text. All other events happen when the sun is in the sky and other for not visible for observation.

January’s sky is a story of starting over for many planets. Mercury, Jupiter and Saturn are all invisible at the start of the month but should be observable with a keen eye by the time February comes into view. Mars and Venus both offer improved views over December but still none of the bright planets are visible at transit (this is the highest point in the sky as they cross the southern horizon.

There’s more detail on all the planets further down the page and the table below can be downloaded as a PDF from the printables section.

All night sky images on this page are courtesy of SkySafari Pro 6. Click here to find out more about the software (opens new tab).

All of the images below can be opened full screen in a new tab by clicking on them


05th Jan

Mercury (and Jupiter & Saturn) is too close to the sun to be observed.

15th Jan

Mercury passed behind the sun on 10th Jan and is still too close to it to be seen.

25th Jan

Finally beginning to reappear, this view of Mercury is half an hour after sunset.

There is little to see of Mercury in January. It is too close to the sun to be observable until the final week of the month and even then it will not be easy. On 25 January (see picture above) the tiny planet is just above the horizon half an hour after sunset, and very close to the one-day-old moon. This is a challenging spot! Have an attempt if you have an unobstructed view of the horizon and know just where you need to look.


05th Jan

This is the view an hour after sunset, Venus is 18° above the southwest horizon and 80% illuminated against Capricornus.

15th Jan

Venus continues to get higher as the month goes on and it moves from Capricornus towards Aquarius.

25th Jan

We can now see Venus well in a properly dark sky. This is the view 90 minutes after sunset.

Venus rapidly improves over the course of January, moving higher in the sky as the days tick past so that, by the end of the month, it is easily observed against a dark background in the early evening.

Illumination of the planet’s surface steadily decreases from just over 80% at New Year’s Day to below 75% by the time we reach February. Oddly, its brightness barely changes and that’s because as its surface illumination decreases it actually moves closer towards us, its bigger disc balances out the smaller crescent.

In the final week of the month the brightest object in our sky after the moon sets more than three hours after the sun leaving us ample opportunity to observe it.


05th Jan

Mars begins the year high over the southeast horizon in Libra at 6am.

15th Jan

Little has changed ten days later. This view is also at 6am.

25th Jan

This is the view half an hour earlier on the 25th of January. Mars has travelled away from Libra by this time.

Mars will put on a spectacular show in the fall of this year but, right now, it’s a small pinprick of red light a few degrees above the south-east horizon before sunrise.

As we come towards the end of the month, it passes by the star Antares which gets its name from its color; it means ‘rival of Mars’. Open the picture above for 25th of January and see that Mars and Antares are just a few degrees apart. Observe them for yourself and see if you agree they shine with a similar hue?

The Martian disc grows fractionally this month but, at just five arc seconds across by the end of January, it is nothing to write home about. Indeed, it is just a fraction larger than the disc of distant Uranus.


05th Jan

Jupiter (and Mercury & Saturn) is too close to the sun to be observed.

15th Jan

Technically rising before the sun now, but practically no chance of seeing it before dawn overwhelms our view.

25th Jan

As the final week of January begins, we might just spy Jupiter above the southeast horizon in the brightening dawn.

Jupiter spends most of January not visible but, towards the end of the month, we should begin to see the gas giant. Over the horizon in the predawn sky. Much better views are assured in February and they will improve throughout the year as we had to opposition in the summer.


05th Jan

Saturn (and Mercury & Jupiter) is too close to the sun to be observed.

15th Jan

The ringed planet passed behind the sun two days ago and is too close to it to be observed today.

25th Jan

Saturn is heading towards early morning visibility, but this is not the day to try. In a week, we might just glimpse the rings.

Saturn does not reveal itself during January, except maybe for the last day or two. On 13 January, the ringed planet passes behind the sun which is why it is too close to our star for us to see it this month.

Happily, visibility will return in February and will keep improving until we reached opposition in the summer.

Uranus & Neptune

15th Jan

This shows Uranus 25° above the western horizon at 11pm.

15th Jan

Neptune is caught in Aquarius, not too far from Venus, at 7pm on the 15th of January.

Neptune and Uranus are both evening objects in January. They both put on better views earlier in the evening, so try and find them as soon as it gets dark.

Uranus shines a magnitude 5.8, putting it near the limit of naked eye visibility in a dark sky. Neptune is at magnitude 7.9 making it invisible to the naked eye so you’ll need to star hop your way to finding it.