We can become very attached (even fondly) to the instruments that give us such a thrill observing the Universe. It can come very hard, then, for us to question their quality. Reviewer Steve Ringwood takes a look through a Ronchi eyepiece that permits the user to obtain a definitive and exacting exposure of a telescope’s optical quality.
At 6am GMT on the mornings of 3 and 4 February, around the onset of astronomical twilight for the centre of the British Isles, the old waning crescent Moon brushes by ringed planet Saturn low to the south-southeast horizon. As a bonus for telescope users, the Moon occults globular cluster M9 shortly after 6am GMT on 4 February too.
This Hubble image is of the peculiar galaxy NGC 1487, lying about 30 million light-years away. We are witnessing the possible merger of several dwarf galaxies into a new single galaxy. Its appearance is dominated by large areas of bright blue stars, illuminating the patches of gas that gave them life. This burst of star formation may well have been triggered by the merger.
As avid skywatchers will already know, all of the bright naked-eye planets are currently visible in the pre-dawn sky — the first time in eleven years that such an alignment has occurred. At 6am GMT on Monday, 1 February, the last quarter Moon in the constellation Libra lies just 2½ degrees from magnitude +0.8 planet Mars low in the south for UK observers.
When the Moon is high in the sky, it produces bulges in the Earth’s atmosphere that create measurable changes in the amount of rain that falls below, according to new research. But no-one should carry an umbrella just because the Moon is rising — even in the tropics, average rainfall rates are only increased by 1/10,000 of an inch per hour.
The Sun’s magnetic field is responsible for everything from the solar explosions that cause space weather on Earth — such as aurorae — to the interplanetary magnetic field and radiation through which our spacecraft journeying around the solar system must travel. But even now, scientists are not sure exactly where in the Sun the magnetic field is created.
Data from NASA’s New Horizons spacecraft point to more prevalent water ice on Pluto’s surface than previously thought. Water ice is Pluto’s crustal “bedrock,” the canvas on which its more volatile ices paint their seasonally changing patterns. The new false-colour image is derived from observations in infrared light by the probe’s Ralph/Linear Etalon Imaging Spectral Array.
A new animation showing a simulated flight over the surface of dwarf planet Ceres using images from NASA’s Dawn spacecraft in its high-altitude mapping orbit has been produced by members of Dawn’s framing camera team at the German Aerospace Center, DLR. The movie emphasises the most prominent craters, such as Occator, and the tall, conical mountain Ahuna Mons.
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