Astro Bob: Asteroid 2023 CX1 explodes over France; Venus greets Neptune

Astronomers discovered an asteroid just hours before it safely struck Earth's atmosphere. And thanks to Venus, we'll easily find Neptune this week.

Fireball Feb 13 2023
This screenshot from a short video (watch it below) captures the fireball and explosion when the small asteroid 2023 CX1 slammed into the atmosphere across England and France early Monday morning, Feb. 13.
Contributed / Kade Flowers

For only the seventh time, an astronomer spotted an incoming asteroid just hours before it crashed to Earth. Krisztián Sárneczky of Hungary recorded the object, now designated 2023 CX1, as faint, fast-moving blip through his telescope.

His observation, paired with others made soon after, quickly revealed that the meteoroid — the name given to very small asteroids — would impact the planet. Sure enough, hours later it lit up the sky in a spectacular fireball display.

Dozens of witnesses from England, France, Belgium and the Netherlands watched a brilliant bolide streak across the heavens and explode in a brilliant flash brighter than the full moon at 2:59 a.m. (London time) Monday morning, Feb. 13. Based on its discovery brightness, the space boulder was about 3 feet (1 meter) across — small enough to harmlessly break up in the atmosphere.

Expert fireball trackers consider it likely that meteorites from the explosion are already on the ground in France's Normandy region. That means meteorite hunters will soon follow. Hopefully, we'll have the first samples in hand of this wayward visitor from the asteroid belt in the next week or two.

Asteroid impact events
This diagram maps the data gathered from 1994-2013 on small asteroids impacting Earth's atmosphere that created bright meteors, technically called bolides and commonly referred to as fireballs. Sizes of red dots (daytime impacts) and blue dots (nighttime impacts) are proportional to the visible radiated energy and show the locations from objects about 3 feet (1 meter) to almost 60 feet (20 meters) in size.
Contributed / NASA Planetary Science

Rocks from space fall all the time. U.S. government sensors recorded 556 small brilliant fireballs from small asteroid strikes from 1994 to 2013. They ranged from 3 feet (1 meter) to almost 60 feet (20 meters) in size. Almost all objects this size disintegrate in the atmosphere and are usually harmless. If we're lucky, fragments of the original asteroid survive and land on the ground as meteorites.


NASA estimates that 10-50 meteorites arrive on the planet every day. Most go undiscovered, but each year roughly a dozen observed meteoroid (small asteroid) falls are recovered by locals and hunters.

Venus and Neptune shake hands

Venus is the brightest planet in our night sky and visible below Jupiter in the southwestern sky at dusk this month. On Monday, Feb. 13, the two shiny "stars" will be just 14° apart. Lurking very near Venus is the faintest and most remote planet in the solar system, Neptune.

Jupiter Venus Neptune
Look southwest to find Venus and Jupiter, then focus on Venus and seek Neptune just a half-degree to its upper-left.
Contributed / Stellarium

On Feb. 14 and 15, the two meet up in a close conjunction I'm hoping we'll be able to see in binoculars. Normally, it takes a bit of work to spot faint Neptune all by its lonesome, but having a bright planet nearby makes the search an easy one. The contrast in brightness between them will be astonishing. Venus shines at magnitude -3.9 and Neptune at 8, a difference of 12 magnitudes or a factor of 60,000.

Venus Neptune conjunction
This simulation shows Venus and Neptune through binoculars. Venus is the big white dot. On Feb. 14 at dusk, it will appear to a half-degree below and right of Neptune. One night later (Feb. 15), Venus shines just above the faint, remote planet. For best results, buttress your binoculars against the side of a building or roof of your car.
Contributed / Stellarium with additions by Bob King

On both nights, only 0.5° (one full moon diameter) will separate these dissimilar worlds. You'll need a pair of 50 millimeter or larger binoculars to pick out Neptune, which will look like a faint star. The best time to view the pair is during late twilight about 90 minutes after sunset. Venus will be low in the southwestern sky at that time. It's possible that binoculars won't be enough, so if you have a small telescope (any will do), try that, too!

If you're successful, think about the true distance between the two planets. They may appear like they're almost touching, but Venus glitters in the foreground more than 21 times closer — 133.4 million miles (214.7 million kilometers) compared to Neptune's 2.9 billion (4.6 billion kilometers)!

"Astro" Bob King is a freelance writer and retired photographer for the Duluth News Tribune. You can reach him at
What To Read Next
Get Local