Author Archives: Allen Versfeld

About Allen Versfeld

Allen is an amateur astronomer, an IT professional, a podcaster, a father of five growing kids, a barely competent chess player, and the owner and publisher of the Urban Astronomer podcast and website. He has formerly served as Director of the Astrophotography and Citizen Science sections of the Astronomical Society of South Africa. You can find his personal social media feed on Mastodon!

GRAIL mission maps Moon’s gravity

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Late last year, a pair of spacecraft completed their mission to probe the hidden inner structure of the Moon by precisely mapping out its gravitational field.  The Gravity Recovery and Interior Laboratory (GRAIL) mission revealed details and features that had never been seen before like tectonic structures, volcanic landforms, basin rings, crater central peaks and many simple bowl-shaped structures. The GRAIL mission worked by sending two small spacecraft (GRAIL-A and GRAIL-B) into the same orbit around the Moon, each about … Continue reading →

How do you define astronomy?

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In an earlier article, I dealt with one of the most annoying questions that astronomers seem to get asked routinely:  “What’s your sign?”  But even more frequent and way more annoying, is being described as an astrologer by people who don’t seem to know the difference between astronomy and astrology!  To help those people, I’m going to answer the question that they never seem to ask, and really should: What is Astronomy? Well, astronomy is a science.  It deals with the … Continue reading →

Why don’t scientists believe in UFO’s?

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A lack of any convincing evidence, mainly.  There have been countless thousands of reports of UFO’s over the last century, but most can be easily explained by natural phenomena or known human activity.  For example, the sighting of a mysterious spinning spiral in the sky above Norway turned out to be a malfunctioning rocket spinning out of control.  Other cases turn out to be the planet Venus (“There’s something hovering above the horizon, as bright as an aeroplane’s landing lights”), … Continue reading →

Nibiru (part 2)

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Return to Part One Planet X New Worlds On 13 March 1781, William Herschel discovered a new planet, which would be named Uranus (God of the Sky, father of Saturn).  This was a huge deal, as it overturned millennia of established knowledge about the Solar System.  Uranus was studied and observed until astronomers were able to plot it’s orbit and predict it’s movements.  Unfortunately, no matter how carefully they refined their figures and checked their calculations, Uranus did not move … Continue reading →

Black Hole

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Science fiction movies love a good Black Hole.  It’s dark, mysterious, dangerous and you can wrap all sorts of interesting plots behind it.  Unfortunately, the traditional bad science penned by script writers gets even worse when black holes are added.  Let’s have a look at some of the properties black holes exhibit in fiction: They are unstoppable celestial vacuum cleaners, sucking up anything that strays close by. If you fall into a black hole, you will be teleported somewhere else … Continue reading →