The late hours of Monday night (24.08.09) brought an opportunity to take in a quick observation of Jupiter with the 25×100 binoculars. Initially I could only discern three of the Galilean moons, but further investigation revealed the fourth elusive satellite — Io — hugging close by Europa. Upon checking ‘The Night Sky’ section in my August edition of Astronomy Now I realised that I was witnessing a burgeoning occultation as Io converged upon Europa. Unfortunately I was unable to watch this entire Jovian event unfold, but it was fascinating to see the wafer-thin gap between the shimmering moons slowly disappear as they drifted towards their celestial rendezvous.
Archive for the ‘Astro Art’ Category
Aug
04
2009
Science Needs You!
Near the end of June I was offered the chance to produce two digital renders for Tavi Greiner’s monthly ‘Our Night Sky’ report over at Astrocast.TV. A passionate stargazer and co-author of the blog: A Sky Full of Stars; Tavi also enthusiastically promotes outreach astronomy to fellow amateurs via Twitter, and FaceBook.
The latest episode of Our Night Sky focuses on citizen science and how members of the public can volunteer their time to make an invaluable contribution to real scientific research. Two projects in particular are highlighted: Stardust@Home and Citizen Sky; the leading project of the American Association of Variable Star Observers.
Stardust@Home are eagerly searching for microscopic grains of comet and interstellar dust obtained during a recent space mission, while Citizen Sky are hoping to unravel the enigma of a mysterious variable star that has puzzled astronomers for 175 years.
To visualise the concepts at the centre of these two projects I employed Photoshop CS2 as well as the combined power of Blender 2.46 and Terragen 2. The first of these renditions (above) is an impression of an interacting binary system on the verge of an eclipse, while the second one (below) depicts the fiery reentry of a spacecraft capsule on it’s return to Earth after visiting a distant comet.
The opportunity to support Tavi’s admirable work over at Astrocast.TV has been a welcome one, and I’ve enjoyed working on these illustrations which have opened my eyes to the vital role that citizen science plays within the scientific community. To quote the American anthropologist Margaret Mead: “Never doubt that a small group of committed citizens can change the world.”
Jul
15
2009
Three Times the Charm
Jupiter, the majestic giant of the solar system, has always been my favourite planet. While Saturn delivers undeniably glorious views; Jupiter, at least for me, has always stolen the show. Having suffered a grueling month of cloudy evenings, and twilight nights, the chance to take in an observation of this dazzling planetary behemoth early on Saturday morning was a welcome one.
The fact that Jupiter was in conjunction with Neptune, and the star µ (Mu) Capricorni just added to the celestial spectacle. My view however was to be a short lived one. Due to the urban geography of the neighbourhood; both planets remained in my sights for only 16 minutes before disappearing behind the row of three storey buildings that line the front of the house.
A Planetary Dance
Despite my brief window of opportunity I was afforded a stunning observation. The 25mm Celestron plössl revealed the equatorial belts of Jupiter as rust coloured bands, while the four moons: Callisto, Ganymede, Io, and Europa beamed like a string of brilliant diamonds against the dark sky. Having conducted my most recent observations of Jupiter with the 25×100 Strathspey binoculars; it was a real pleasure to see this distant world with such clarity.
While Jupiter made a striking impression; Neptune, bathing in the alabaster light of the waning gibbous Moon, was just discernible as a faint point of light with a hazy turquoise hue. This is the second time that I have been fortunate enough to view this remote ice giant which sits just over 2 billion miles from the Earth. Gazing upon this diminutive speck you realise that you are actually looking at the end of planetary space beyond which begins the Kupier belt, the Oort cloud, and finally galactic space. An amazing, but rather humbling thought.
In between this planetary dance µ Capricorni, a yellow-white F3 IV type subgiant that lies 90.2 light years away, cast it’s white incandescent light upon the scene. Subgiants are stars which have, or are in the process of ending hydrogen fusion. Beyond this point in it’s evolution µ Capricorni is destined to become a red giant that may, at some point in the far flung future, bloom into a planetary nebula.
As quickly as Jupiter, and Neptune had risen above the roof tops then no sooner were they gone. Hidden from view by the suburban sprawl. Left alone with the Moon, which made for a very tempting target, I decided to make the most of it by taking in one more special observation before packing up.
One Giant Leap
Forty years ago, on the 20th of July 1969, NASA realised the mandate that the late President John F. Kennedy had laid down eight years earlier: to land a man on the Moon, and return him safely to the Earth. Apollo 11, carrying the astronauts Neil Armstrong, Michael Collins, and Edwin ‘Buzz’ Aldrin, set down near the south western shore of the Mare Tranquillitatis, and made history.
It was here that I aimed the telescope in search of three small craterlets: Aldrin, Collins, and Armstrong; all of which form a chain just east of the larger impact craters Ritter, and Sabine. After ten minutes of continued scrutiny the 6mm plössl finally resolved these three small monuments to the first manned lunar landing. In reality Aldrin, Collins, and Armstrong range in size from 2.4 Km to 4.6 Km giving some idea of just how vast this region of the Moon really is.
Letting my gaze drift down not far from Collins I imagined the quiescent remnants of Tranquility Base, also known as Statio Tranquillitatis, forever frozen in time by the vacuum of space. A lasting testament not only to the triumph of Apollo 11, or the United States of America, but probably the single greatest achievement Mankind has ever made. Where the 21st Century will take space exploration is anyone’s guess, but hopefully one day humanity will find itself once again voyaging to the Moon, and beyond.
If you have the time then why not follow in the footsteps of the Apollo 11 astronauts by tracking down the craterlets Aldrin, Collins, and Armstrong yourself. The best time to do this is nearer the end of the month, on the 27th of July, five days after the new Moon. I’d also recommend that you take in an view of Jupiter, and Neptune as they drift past one another in the night sky. This is the second of three conjunctions that will take place between these two planets during the year, with the third one to occur on the 20th of December. Have fun, and happy observing!
Jun
09
2009
Moon Safari
The Moon is, and always has been a favourite observing target of mine. So when last weekend (30.05.09) brought some beautiful clear skies with it; I took the opportunity to explore some new lunar locations as well as revisit some old ones. There was so much to see that I couldn’t possibly fit it all into this blog post. However two features that really stood out for me were: Rima Ariadaeus and Rima Hyginus; both impressive rilles that lie near the west coast of the Mare Tranquillitatis.
The word rille is used to describe the various depressions, or trenches that can be seen scarring the surface of the Moon. The term was used by early observers to characterize such lunar objects and was probably introduced by the German astronomer Johann Schröter in about 1800. More recently the latin word rima (meaning fissure) is often used interchangeably with the word rille to describe the same kind of feature.
Rilles can be divided into three categories: linear, arcuate and sinuous. Those of the first type are thought to be grabens: extended slabs of crust that have collapsed between parallel faults. They are comparatively straight, flat-floored and are sometimes associated with crater chains. In comparison arcuate rilles have smooth curves and are often observed near the edges of the lunar maria. They are believed to have formed when the lava that established the maria cooled, contracted and sank. The sinuous variety seem to be similar to the channels that lava flows on Earth produce, but these lunar valleys are far more rambling; perhaps because the ancient lavas that spread across the Moon were more fluid than those found on Earth.
The shadowy laceration of Rima Ariadaeus, a 300 Km long graben, offered a wonderful view through the five inch refractor. At around 3.85 to 3.2 billion years old this lunar fault formed some time between the late, or early Imbrian epochs. A violent period characterized by colossal impacts and vast volcanic eruptions that formed the lunar maria that we see today.
Conversely Rima Hyginus proved just a little harder to find, but only because I had chosen to look for it when low light conditions were not at there optimum. This hybrid rille, also an Imbrian formation, evolved through a fault that was subsequently altered by volcanic activity. Closer inspection of this lunar feature reveals that it ramifies by adjoining Rima Ariadaeus via a shallow groove towards the north east.
Both of these rilles made for wonderful viewing and testify to the Moon’s tumultous past. So if you haven’t done so already I would thoroughly recommend that you take in an observation of these two fascinating lunar objects. A minimum aperture of around 90mm is almost certainly needed, and I would advise searching for them both around six days after a new Moon, or five days after a full Moon. Just be careful that you don’t get stuck in a groove!
May
21
2009
Doubling Up
I began a short observing session last Tuesday morning (12.05.09) by trying to split the well known double star Izar (also known as Epsilon Boötis) in the constellation of Boötes. Despite a hazy mist in the upper atmosphere conditions were fairly decent, but try as I might I just couldn’t separate the orange giant primary, and it’s smaller main sequence companion from each other. I was sure that a power of 166x would be up to the job, but obviously it wasn’t so perhaps someone can offer a little advice on the subject?
After about twenty minutes of fruitless scrutiny I decided to move on from Boötes to bathe in the radiance of my second morning target: Cor Caroli in Canes Venatici. The view through the 6mm plössl was delightful, but unexpectedly, and quite oddly the brighter A class primary shone with a greenish hue rather than the white or pale blue luminosity that I was anticipating. The secondary which is an F class star should have displayed a yellow iridesence, but instead showed no sign of colour.
Regardless of the perculiar spectral colours that I percieved this really was an attractive binary system to study, but I think it will be one that I will return to quite soon for a follow up observation.