What's Up - March 2023
What are some skywatching highlights in March 2023? Following their close approach in the sky on March 1, Venus and Jupiter go their separate ways. Venus climbs higher each evening, while Jupiter exists the morning sky at month's end. And those with binoculars of a small telescope can seek out dwarf planet Ceres, which is at its brightest this month.
What's Up for March? Venus climbs high while Jupiter dives sunward, and the little planet that shares its namesake with your breakfast cereal.
Venus and Jupiter begin the month very close together in the evening sky, following their close conjunction on March 1st. They quickly go their separate ways, though. Venus climbs higher in the sky each night for the next couple of months, while Jupiter dives after the Sun. The giant planet appears lower in the sky each night through the month, making its exit as an evening object. It'll reappear in May, in the pre-dawn sky, with Saturn.
On the 23rd and 24th, in the couple of hours after sunset, you'll find the Moon as a beautifully slim crescent hanging just below, and the next night above, blazing bright Venus. Then, on the 25th, the Moon continues upward in the sky, landing right next to the brilliant Pleiades star cluster that night.
With March bringing the arrival of spring in the Northern Hemisphere and fall in the Southern Hemisphere, it's a time for both planting or harvesting crops, depending on where you live. So it's perhaps a fitting time to try and spot the planet named for a mythical goddess of agriculture, grains, and fertile lands. (In addition to being the origin of the word "cereal.")
That's dwarf planet Ceres. This month it's at opposition, meaning it's directly on the opposite side of Earth from the Sun. This is when a planet is around its shortest distance from Earth, making this the best time to have a go at observing it when it's at its brightest.
Ceres is the largest object in the main asteroid belt between Mars and Jupiter. Still it's only about 600 miles wide – far smaller than our own Moon. Its dusty surface is peppered with impact craters, with bright salt deposits here and there, that hint at the possibility of slushy, briny ice beneath. In fact, NASA's Dawn spacecraft found that Ceres could be up to one-quarter water ice on the inside.
Now, Ceres is too faint to see with the unaided eye, so to locate it in the March sky, you'll need binoculars or a small telescope. Find the lion constellation Leo in the southeast after around 9pm. The bright, bluish-white star Regulus (the lion's heart) should catch your eye first. Then look eastward about 25 degrees to find Denebola, which represents the lion's tail. From there Ceres should be 8 or 9 degrees farther east from Denebola. It appears as a faint, star-like point of light – which is why, when Ceres and objects like it were first discovered in the early 19th century, they were called "asteroids," which means "starlike."
Since 2006, Ceres has been classified as a dwarf planet – along with other diminutive worlds in our solar system including Pluto, Eris, Haumea, and Makemake. Wherever you land on the topic of "planet vs. dwarf planet" -status for worlds like Ceres and Pluto, what's really important to remember is that the way we think about different families of objects in our solar system has evolved over time, and likely will continue to evolve as we explore and learn more about them. So here's hoping you try your hand at spotting Ceres as you explore the skies above your home planet this month.
Here are the phases of the Moon for March. Stay up to date with all of NASA's missions to explore the solar system and beyond at nasa.gov. I'm Preston Dyches from NASA's Jet Propulsion Laboratory, and that's What's Up for this month.