Goodbye – Cassini’s Last Splendiferous Hurrah
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        The English language is lacking in positive affirmations glowing enough to encompass the significance of the Cassini Mission to Saturn. Side winding its way into my mind in the effort to find the right words came a memory of an old TV variety show. In the show, the host announces the artists to perform by pronouncing very large words in rapid precision. Each word is preceded by a judgemental gavel blow. The hyperbolic introductions primed the audience to welcome the splendiferous offerings of the forthcoming show. The pulchritudinous (excellent) nature of the mission has produced an abundance of most noteworthy images. The collection can spectacularly stimulate our senses to levitate our minds and souls. Cassini therefore invites us to relish the beauty of Saturn and its many moons. NASA has magnanimously offered the images videos and gifs to all who wish to enjoy the resplendent wonder of this epic mission. If the same host was to … Continue reading

In the Sky this Week- September 19, 2017
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A veritable riot of conjunctions is happening all week in the eastern predawn skies; Venus is VERY close to the star Regulus, and Mercury and Mars continue to be low in the sky before sunrise. These conjunctions can also be seen from the southern hemisphere; note how the position of the planets differs from the northern hemisphere. Saturn continues to be a good observing target in the southern skies after sunset. The southern skies seen from Perth after sunset are something I’d REALLY like to see; visible are the two Magellanic Clouds, the Carina Nebula In the eastern sky seen from Perth at 1:00 AM on Sept. 18th we see a good example of the different orientation of constellations seen from the southern hemisphere. The Pleiades star cluster can be seen high in the eastern sky at 2:00 AM. The Pleiades open star cluster consists of approximately 3,000 stars, and is among the nearest star clusters to Earth; the cluster … Continue reading

A Heartfelt Farewell to NASA’s Cassini Mission to Saturn
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The Cassini mission to Saturn ranks right at the top of my list of favorite space missions; this morning, on NASA TV, I watched Cassini’s final moments as it plunged into the atmosphere of Saturn… and I had a good cry. It’s an odd juxtaposition of feelings: being overjoyed and incredibly sad at the same time. When Cassini launched in 1997, my daughters were aged 12 and 9; my wife likes to recall the story of my phoning my eldest in 2004, then in college, to tell her that Cassini was making its orbital insertion burn! She also claims that I can be “such a geek.” Yesterday, I heard a story on NPR with a NASA engineer that was at the very first Cassini planning meeting – 30 years ago! For several people, this mission has been their entire career! In an interview I heard this morning, one mission specialist said that most of what’s in recent science textbooks about … Continue reading

In the Sky this Week – September 12, 2017
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Mercury is about as high as it’s going to get in the eastern predawn sky on the 12th, and will start getting lower each morning. Sirius is high in the sky, and the constellation Canis Major is now fully visible above the southeastern horizon before sunrise. Mercury and Mars will appear very close to each other in the eastern predawn sky on the 16th. Saturn continues to be a great observing target in the southern sky after sunset. The Moon will be in conjunction with the star Aldebaran on the morning of the 12th, and will appear between(ish) the stars Aldebaran and Betelgeuse on the 13th. The eastern predawn sky on the 18th should look pretty interesting: Mercury, Mars, a sliver of a waning crescent Moon, the star Regulus and Venus will all appear in a line. Sunspot AR2680 has rotated into view; this sunspot is about the same size as AR2673 was from last week – which ballooned out and blew off … Continue reading

In the Sky this Week – September 5, 2017
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Mercury and Mars make a reappearance very low in the eastern morning sky – so low in fact, you may have trouble seeing them if you have low shrubs; atmospheric turbulence and light pollution may also make them difficult to spot. Over the week, Mars will not get any higher in the sky, but Mercury will get visibly higher each morning. Mercury will be very close to the star Regulus in Leo on Sept. 10th. Catch Mercury while you can – by next week, Mercury will start getting lower in the sky, and will vanish entirely by late September. The full Moon rises in the east with the sunset on Sept. 5th; Saturn remains high in the southern sky, after sunset. Polaris, the North Star, is visible above the northern horizon before dawn. Two of Polaris’ three stars can be made out in a modest sized telescope; Polaris A, the primary component of the trinary is a Cepheid variable star, … Continue reading

In the Sky this Week – August 29, 2017
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The eastern sky before sunrise is getting busy! Venus is accompanied by several bright stars, and the easily recognizable constellation of Orion is higher each morning; winter stars are on their way! There will be a conjunction of Saturn and the Moon in the southern sky on the nights of the 29th and 30th; the first quarter moon will be very close to Saturn, and likely wash it out a bit when observing through a telescope. The Constellation Cygnus is overhead after sunset, and the star Albireo, makes for a very interesting object through a small telescope. To the naked eye, Albireo appears to be a single star; in a telescope, it resolves into a beautiful gold and blue double star. Tip: If you slightly unfocus your telescope when observing Albireo, the colors will spread out, and you can see them a bit better. It is unknown if Albireo is a true binary star, or an “optical double” – a … Continue reading

In the Sky This Week – August 22, 2017
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Sirius, the “Dog Star,” accompanies Venus low in the eastern predawn sky. Jupiter sets shortly after dusk and will vanish from view entirely in a early September. Saturn is high in the southern sky, and with the planet’s northern hemisphere tilted towards us at about 26°, Saturn is just a spectacular observing target. The Moon, fresh from the eclipse, will be in conjunction with Jupiter in the west at dusk on August 24th and 25th. The Moon will be a waxing crescent in the west at dusk, growing larger each evening until it is at first quarter on August 28th; the later part of this week will be excellent nights for star parties. Sirius, the brightest star in Earth’s sky, is a binary star system about 8.6 light years away. Sirius A is a bright and hot main sequence star, with a faint white dwarf companion: Sirius B. Sirius A is class A0 star about twice the mass of the … Continue reading

In the Sky This Week – August 15, 2017
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Venus is a bit lower and Orion a bit higher in the eastern morning sky. Venus orbits closer to the Sun than Earth, and is racing ahead-of and away-from the Earth; the planet will vanish from view in mid-November as the Sun comes between it and the Earth. The waning crescent Moon appears thinner and closer to the horizon each morning in the eastern sky. Note: I used Stellarium’s new “Astronomical calculations” feature to generate the ephemeris for this image – I expect you’ll be seeing more of this. The Moon be in conjunction with the star Aldebaran on the Aug. 16th, appearing VERY close to each other, VERY early in the morning. Aldebaran is a orange giant star about 44 times the size of the Sun, located about 65 light years away. Aldebaran is positioned close to the ecliptic plane, and is frequently occulted by the Moon… just not this month. Jupiter is visible only for a short time … Continue reading

In the Sky This Week – August 8, 2017
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Venus is a bit lower in the eastern predawn sky, and Orion is fully visible now before sunrise. The waxing gibbous Moon, just days after full,  rises in the east with the sunset, and sets in the west with at dawn. Jupiter is low in the western sky, and visible for only a short time. Saturn is high in the southern sky after sunset, and sets about 2:00 AM. The Perseid Meteor shower peaks the evening of August 11-12th; the Moon will be at Third-Quarter on August 14th. Apps used for this post: Stellarium: a free open source planetarium app for PC/MAC/Linux. NASA Eyes on the Solar System: an immersive 3D solar system and space mission app – free for the PC /MAC. Also in In the Sky This Week Weekly post on what you can see in the sky. In the Sky This Week – June 22, 2017 In the Sky This Week – June 27, 2017 In the Sky This … Continue reading

In the Sky This Week – August 1, 2017
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Venus is still high in the eastern morning sky; the constellation Orion appears a bit higher each morning. The southern sky is filled with objects this week: the waxing gibbous Moon accompanies Jupiter and Saturn for several days. The Moon will appear very close to Saturn on the evening on August 2nd. The constellation Cetus appears in the predawn sky to the southeast. Cetus is depicted as a sea monster in Greek mythology, but is often referred to as “the whale” today. I know several astronomers who had a copy of H.A. Rey’s “The Stars: A New Way to See Them” when they were young – I still have my copy! I was overjoyed to see that Stellarium has a starlore set depicting constellations as drawn by H.A. Rey in his book. The constellation Cetus in Stellarium as drawn by H.A. Rey in his book “The Stars: A New Way to See Them.” The sky overhead – Aug 1, 2017 … Continue reading

In the Sky This Week – July 25, 2017
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Venus is still bright in the eastern predawn sky, but a little bit lower each morning. The constellation Orion is rising with the dawn; a little more of the constellation visible each morning. A wafer-thin waxing crescent Moon will be visible for a short time after sunset in the west on July 25th. Jupiter is visible low in the southwestern sky, and will be a little lower in the sky each evening after sunset. Saturn is high in the southern sky, and is a great target for telescope observers. Jupiter will be a scant 3° South of the Moon after sunset on July 28th. The Moon will be at First Quarter on the evening of July 30th, surrounded by Jupiter and Saturn, and the Southern Delta Aquariids Meteor Shower peaks on July 29-30th; this would be a great evening to host an astronomy outreach event! Apps used for this post: Stellarium: a free open source planetarium app for PC/MAC/Linux. NASA … Continue reading

In the Sky This Week – July 18, 2017
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Venus continues to dominate the morning sky in the east, but appears slightly lower in the sky each morning as it pulls ahead of us in its orbit. The waning crescent Moon will appear near Venus the the star Aldebaran on the mornings of July 19th and 20th. The New Moon will be on the 23rd. Jupiter and Saturn appear in the south-southwestern sky after sunset; Jupiter will appear slightly lower in the western sky each day as the Earth pulls ahead of Jupiter in its orbit. The constellations Pegasus and Andromeda appear low in the northeast sky after sunset; the wispy cloud of M31, the Andromeda galaxy, makes a good target for telescope observers. M31 is the nearest major galaxy to the Milky Way. It is 2.5 million light years distant, and heading straight at us; in a little over 4 billion years, it will collide with the Milky way, and the two galaxies will merge into a large … Continue reading