Bob Trembley

About Bob Trembley

Bob is a lifelong amateur astronomer, the Outreach Officer for the Warren Astronomical Society, and a volunteer NASA/JPL Solar System Ambassador. Bob does a lot of astronomy outreach - he lectures about astronomy and space science, and sets up his telescopes at schools, planetariums, conventions, and other venues. From 2014-2016, he was the editor of the Warren Astronomical Society's newsletter.

Bob is fantastically interested in asteroids and near-Earth objects (NEOs), and a HUGE fan of Kerbal Space Program; he is determined to improve the teaching of astronomy and Space History throughout Michigan, and the U.S.

Rocket in Flight
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In the Sky this Week- September 19, 2017

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

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

An Introduction to the Universe: The Big Ideas of Astronomy

Now You Know Media presents a new lecture series with Br. Guy An Introduction to the Universe: The Big Ideas of Astronomy In these 12 lectures, Br. Guy Consolmagno, S.J., Ph.D. leads you on a journey through the Cosmos; you’ll learn how the stars and planets reveal the beauty of Creation, and explore Scripture, the great astronomers, and the most profound questions about the universe. Topics include: Naked Astronomy: How can we to learn the sky, to recognize its regularities and its changes, and find God in the rhythm of the stars? Dark skies: For most of human history, nightfall meant the absence of light, a daily shift of what we could and could not do. How has the ubiquitous presence of artificial light changed the way we the spirituality of preserving our view of the heavens Astronomy in the Bible: How does scripture talk about the stars? What can we learn today about the best way to appreciate the … Continue reading

In the Sky this Week – September 12, 2017

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

Become a Volunteer NASA/JPL Solar System Ambassador

NASA/JPL is looking for highly motivated volunteers to communicate the science and excitement of NASA’s space exploration missions and discoveries to the people in their communities. Each September, the volunteer NASA/JPL Solar System Ambassador program has a recruitment drive for new volunteers; there are currently volunteers from all 50 states, Puerto Rico, Guam, the District of Columbia and the US Virgin Islands. SSAs are required to do a minimum of four events over the year, and log them on the SSA website; events can include: lectures, workshops, star/eclipse parties, hands-on activities, etc. The SSA program hosts frequent teleconferences with NASA scientists, mission specialists, and engineers covering a HUGE range of topics; presentation materials and media for each teleconference are made available for SSAs to use. When it can, the program also provides freebies; my wife and I received 1000 solar glasses and distributed them far and wide before the eclipse. Applicants that are accepted into the program are required to … Continue reading

Sun Spots, CMEs, and Solar Storms!

Oh my! Sol apparently didn’t get the memo that it’s past solar maximum, and time to be heading towards solar minimum. There are a couple massive sunspot groups (Active Regions) on the Sun, and one in particular has magnetic fields harboring enough energy to generate X-class solar flares. AR2674 hasn’t changed much in size over the the last few days, but it is still a very active region with large coronal loops. AR2673 was an innocuous little spot last week, then over the weekend ballooned out into an area larger than the Earth, with intense magnetic fields. On September 4th, AR2673 spit out a Coronal Mass Ejection (CME) towards Earth – due to hit Earth’s magnetic field today (Sept. 6th), and causing G3-class geomagnetic storms on September 6th and 7th; effects can include: GPS problems, intermittent HF radio, spacecraft surface charging, power system voltage corrections, etc… Aurora watchers may want to keep an eye on the Auroral Oval, as increased auroral activity … Continue reading

In the Sky this Week – September 5, 2017

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

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

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

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

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

Perseid Meteor Shower 2017: Aug. 11-12

The Perseid meteor shower is a very popular annual event, with Perseid parties being held around the globe each year. Best seen from the northern hemisphere, the meteors will appear to radiate from a point in the constellation Perseus – between the “W” of the constellation Cassiopeia, and the bright star Capella (see image above). Every year I see posts about this year’s shower being the “shower of the century” or it will be the “brightest shower in the recorded human history!” I’m not so sure about that this year… although the Perseids typically puts on a pretty good show at about 100 per hour, the waning gibbous Moon will be bright, and just to the east of the radiant; this will obscure many of the dimmer meteors. Peak: August 11-12 Active from: July 13th to August 26th Radiant: 03:12 +57.6° (see image above) Hourly Rate: 100 Velocity: 37 miles/sec (swift – 60km/sec) Parent Object: 109P/Swift-Tuttle Source: American Meteor Society … Continue reading