Monthly Archives: January 2018

‘Oumuamua’s Many Cousins

The interstellar asteroid 1I/2017 U1 (otherwise known as 1I/’Oumuamua) is fast receding into the distance, towards the constellation of Pegasus (1).  The existence of this rocky visitor from the stars was announced last October (1).  Its trajectory was too fast for it to be a solar system comet – even one from the furthest reaches of the Oort Cloud.  That was an exciting discovery, because that meant that 1I/2017 U1 was the first confirmed observation of an object arriving in the solar system  from deep space.

Although 1I/2017 U1 was initially considered to be an interstellar comet, that thinking changed when it failed to emit any gases as it performed its perihelion transit around the Sun (3).  This barren rock, confirmed as an interstellar asteroid (4), is now speeding away from the Sun.  It spent a relatively short time in the observation zone of professional telescopes, thanks to its great speed, but this was enough to reveal more weirdness (5).  It is an elongated object spinning head over tip, doing cartwheels through the solar system.  Some wondered whether it might be artificial, given the lack of coma as it traversed past the Sun.  But attempts to pick up signals from the object came up blank (6).  Still, its shape is nothing like any known body in our Solar System.  If solar system asteroids resemble rocky potatoes, then 1I/2017 U1 is more like an interstellar carrot, spinning haphazardly through our system.  To remain intact under these conditions, its internal structure must be robust (7).

The colour of our interstellar carrot is neutral with a reddish hue.  The colouration may be patchy across its surface. Solar system minor bodies (asteroids, Kuiper Belt Objects, Trojans) vary in colour, often dependent upon which population group any particular object belongs to.  Continuing my daft vegetable analogy, solar system potatoes come in different varieties.  Many are neutral in colour, some are reddish, others distinctly red.  Like comparing a Maris Piper to a King Edward.  If we compare 1I/’Oumuamua’s colouration to those of various classes of solar system objects, then it seems to most resemble those of the dynamically excited populations of Kuiper Belt Objects.  However, it is less red than the scattered Trans-Neptunian objects whose orbits extend beyond the heliopause (7).

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Book Review: ‘The Gods Never left Us’ by Erich von Däniken

‘The Gods Never Left Us’ by Erich von Däniken
2018, New Page Books
$17.99
ISBN 978-1-63265-119-8

It’s tricky to remark on how amazing it is that Erich von Däniken is still writing prolifically in his 80s, without sounding just a bit patronising.  Nowadays, his books feel like extended letters sent from his mountain home in Switzerland.  He’s still analysing, arguing, questioning, probing.  He bangs the same old drum, of course, but brings into the mix the newest scientific research, and the latest progress on the long, tortuous path towards disclosure.  This helps to keep his newer books fresh and up-to-date.  Erich von Daniken’s early work has spawned a media phenomenon in the form of the successful ‘Ancient Aliens’ TV series.  By comparison, books must seem a quaint anachronism from the point of view of the newer generations.   But I appreciate them, being a bit of an old hand myself, and I’m glad he’s still writing them!

This particular instalment kicks off with a fictional short story involving CERN and time travel, and the desire to be listened to by the gatekeepers of Knowledge.  It would be too easy to psychoanalyse this short story and place von Däniken in the role of the central protagonist.  It’s a curious thing to include in a non-fiction book, but, as with all von Daniken’s writing, it is enjoyable to read and engaging.

If there is a theme running through the book, it is signs from above.  The Fatima sightings set the scene, dealt with briefly here.  I suppose that the October 2017 event near Fátima, Portugal, which is held dear by the Roman Catholic Church, would be interpreted as a Close Encounter of the Fifth Kind by modern ufologists, in the sense of being a pro-active, human-initiated event involving a UFO-related phenomenon. 

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New Infra-red Search for sub-Brown Dwarfs Planned

Brown dwarfs are notoriously hard to find.  It’s not so bad when they are first born: They come into the Universe with a blast, shedding light and heat in an infantile display of vigour.  But within just a few million years, they have burned their available nuclear fuels, and settle down to consume their leaner elemental pickings.  Their visible light dims considerably with time to perhaps just a magenta shimmer.  But they still produce heat, and the older they get, the more likely that a direct detection of a brown dwarf will have to be in the infra-red spectrum.

This doesn’t make them much easier to detect, though, because to catch these faint heat signatures in the night sky, you first need to have a cold night sky.  A very cold night sky.  Worse, water vapour in the atmosphere absorbs infra-red light along multiple stretches of the spectrum.  The warmth and humidity of the Earth’s atmosphere heavily obscures infra-red searches, even in frigid climates, and so astronomers wishing to search in the infra-red either have to build IR telescopes atop desert mountains (like in Chile’s Atacama desert), or else resort to the use of space-based platforms.  The downside of the latter is that the telescopes tend to lose liquid helium supplies rather quickly, shortening their lifespan considerably compared to space-based optical telescopes.

The first major sky search using a space telescope was IRAS, back in the 1980s.  Then came Spitzer at the turn of the century, followed by Herschel, and then WISE about five years ago.  Some infra-red telescopes conduct broad searches across the sky for heat traces, others zoom in on candidate objects for closer inspection.  Each telescope exceeds the last in performance, sometimes by orders of magnitude, which means that faint objects that might have been missed by early searches stand more of a chance of being picked up in the newer searches.

The next big thing in infra-red astronomy is the James Webb Space Telescope (JSWT), due for launch in Spring 2019.  The JSWT should provide the kind of observational power provided by the Hubble Space telescope – but this time in infra-red.  The reason why astronomers want to view the universe in detail using infra-red wavelengths is that very distant objects are red-shifted to such a degree that their light tends to be found in the infra-red spectrum, generally outside Hubble’s operational parameters (1).  Essentially, the JWST will be able to see deeper into space (and, therefore, look for objects sending their light to us from further back in time when the first stars and galaxies emerged).  Read More…

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