Out of Space

Lunar landing by Indian space probe

Duncan Steel Sep 06, 2019

All being well, the Indian space probe Chandrayaan-2 now in orbit around the Moon will drop its lander safely and softly onto the surface on Saturday morning. The lander (named Vikram) will then roll out its rover (Pragyan), which it is hoped will prowl around for the next two weeks before the cold of the lunar night closes it down. Read More

An invitation to name a star and a planet

Duncan Steel Sep 04, 2019

The International Astronomical Union (IAU) — the global organisation of professional astronomers — is marking its centenary this year by inviting different nations to propose names for both a distant star, and a planet found to orbit it (a so-called exoplanet). Anyone can suggested a moniker, for the star, for the planet, or both. So: calling all New Zealanders to … Read More

The fires in Brazil in satellite imagery: Part 1

Duncan Steel Aug 31, 2019

The numerous fires now burning in Brazil have been much-discussed of late, with world leaders complaining that the nation’s authorities allowing such clearing of land is highly detrimental to international efforts to limit the release of more carbon dioxide into the atmosphere, with the potential to exacerbate anthropogenic global warming/climate change. In this post I illustrate how such fires may … Read More

Remembering Apollo 11

Duncan Steel Jul 18, 2019

There are lots of ways of remembering the Apollo project, which resulted in a dozen men walking on the lunar surface (and some of them even driving around in their lunar buggies). Here I show a few of them, dear to my heart.  You may not have heard, but this weekend marks the 50th anniversary of Apollo 11, when we … Read More

Apollo 11 and the Real Dish

Duncan Steel Jul 16, 2019

The TV pictures of Neil Armstrong clambering down the ladder of the Apollo 11 Lunar Excursion Module and taking the first steps by a human on the Moon’s surface are rightly iconic, though rather fuzzy. Most people seem to think that those images were received by the radio telescope at Parkes in New South Wales, largely because that was what … Read More

The Equation of Time

Duncan Steel Jul 14, 2019

The solstice on June 22nd marked the shortest duration of sunlight (or day length) during this year. One might have expected that from that date sunrise would have started getting earlier; and prior to that date sunset to have been consistently getting earlier (as the daylight duration was shortening). In fact the latest sunrise did not occur until almost a … Read More

Orbits of the satellites launched by Rocket Lab three days ago

Duncan Steel Jul 02, 2019

On Saturday June 29th Rocket Lab launched another cluster of seven satellites into low-Earth orbit from the Mahia Peninsula in New Zealand’s North Island. In this blog post I illustrate the orbital paths of the ten resultant tracked items now in orbit.  In a blog post last week (June 27th) I showed the orbits of the various satellites launched … Read More

Asteroid Day… and what may follow

Duncan Steel Jun 30, 2019

The Tunguska explosion in 1908 was due to the arrival of a small (perhaps 50 metre) cosmic object, quite likely a fragment of a known comet. Astronomers are now wondering whether siblings of that projectile might pass close by the Earth over the next week or so.  I write tonight on Asteroid Day, which occurs on June 30th each … Read More

Tracking satellites launched from NZ

Duncan Steel Jun 27, 2019

With so many thousand satellites now in orbit, and tens of thousands of other tracked items, one might think that it is difficult keeping tabs on them, simply as an interested person. In fact it is quite straightforward, with long lists of orbital elements freely available for all except the few satellites deemed by the US Government to require secrecy, … Read More

The day the Sun stood still

Duncan Steel Jun 25, 2019

We have just passed the solstice, the shortest day of the year in the southern hemisphere. From now on, the hours of daylight will get longer through until the December solstice. Here I discuss why the June solstice occurs a few days before the Feast Day of St John the Baptist, the traditional time of ‘midsummer’ in the northern hemisphere … Read More