Out of Space

When is the day inserted into a leap year?

Duncan Steel Feb 24, 2020

Surprisingly enough, one could argue (as I often do) that the day inserted into a leap year is not that we label 29th February, but actually the 24th of February. Here I explain why, briefly.  Almost everyone assumes that the day added into February in a leap year is the 29th, but that assumption is based on a lack of … Read More

New launch of 60 SpaceX satellites crossing NZ

Duncan Steel Feb 22, 2020

Last Monday SpaceX launched another clutch of Starlink satellites into low-Earth orbit, bringing up to 300 the number of these units intended to bring 5G internet to the whole globe. In this post I present a movie showing how all 300 such satellites will be zipping around our planet over the next eight days (until the end of the month), … Read More

Update on how to see the Space-X satellite chains from NZ

Duncan Steel Feb 08, 2020

In a previous post I described briefly when and how the Starlink satellite chains – recent launches by Space-X in a scheme to bring 5G internet connectivity to the whole globe – could be seen from New Zealand with the naked eye. Here I provide an update and predictions for the next several days.  My preceding post included … Read More

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Seeing the Space-X satellite chains from NZ

Duncan Steel Feb 04, 2020

Space-X has started launching its Starlink satellites into low-Earth orbit with a plan to use some tens of thousands of these to deliver 5G wifi to the whole globe. Chains of these satellites can be seen in the evening or before-dawn skies, through the sunlight they scatter. Here I provide a movie showing opportunities for spotting such satellites over the … Read More

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Southern Cross and Pointers Painted Large Across Christchurch

Duncan Steel Dec 25, 2019

Using knowledge of when the Sentinel-1A radar satellite was due to pass over New Zealand, a team at Christ’s College laid out specially-constructed radar retroreflectors across Hagley Park in Christchurch, in that way painting the Southern Cross and the Pointers in a huge array clearly visible in the derived radar image of the city.  A special – but brief – … Read More

Kiwi exoworlds are named

Duncan Steel Dec 20, 2019

The International Astronomical Union (IAU) this year invited nations to propose names for distant stars selected on the basis of having planets (exoplanets) discovered to be orbiting them. The New Zealand entries, now adopted officially by the IAU, are Karaka for the star, and Kererū for its associated exoplanet.  In a previous blog post I described how New Zealanders had … Read More

Among my favourite asteroids: (2472) Bradman

Duncan Steel Nov 25, 2019

There are many thousands of asteroids with formal names, some humdrum but other more noteworthy (depending on your predilections). One of my favourites, the name of which I was involved in suggesting, is (2472) Bradman, named for the Australian cricketing great. After discussing (2472) Bradman, I also make some comments about (6581) Sobers.  As a minor planet (synonym: asteroid) spotter, … Read More

JFK’s assassination: a bit of physics

Duncan Steel Nov 22, 2019

There are perennial arguments about the circumstances of the assassination of President Kennedy in 1963, and in particular whether more than one shooter is required by the evidence (such as the Zapruder film). Those who know little about physics frequently claim that the sharp backwards motion of JFK’s head as the fatal shot hit him is proof that there must … Read More

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Earth’s artificial rings

Duncan Steel Nov 20, 2019

Satellites pass over NZ all the time (literally). Here I focus on the 187 Planet Labs ‘Dove’ Earth-imaging satellites, and I show that one can determine in advance where they will be, enabling scientists on the ground to correlate their environmental and other data collection with opportunities to get imaging from space. That is, we can get ‘space-truth’ (rather than … Read More

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