Sidewalk Astronomy and John Dobson

Have you ever been stopped by a person on a city street who is standing next to a telescope inviting you to look up at Jupiter or the Moon or Saturn or even sunspots? Sidewalk Astronomers enjoy doing just this, planting themselves at busy intersections or interesting locations with a telescope and a smile and willingness to share the cosmos with anyone who happens across them. There is no special membership needed to be a sidewalk astronomer, just a 'scope and a socially-minded demeanor.

There is a worldwide association of Sidewalk Astronomers

Huge Hand-Made Dobsonians

, a loosely organized bunch of urban guerrillas who enjoy standing on the street corners of the world sharing their love of the heavens. I've done this myself from time to time, although I tend to focus more on public 'star parties' and events such as the Mt. Tam Astronomy Nights or Yosemite National Park where I connect with visitors and share the night sky. But all of the amateur astronomers around the world owe a debt of gratitude to John Dobson, the first sidewalk astronomer. John was passionate about sharing the sky with everyone on the planet, did so with countless hours on the sidewalks of San Francisco and elsewhere, and revolutionized the world of amateur astronomy with the development of a telescope design that now bears his name, a design that is relatively easy to construct from low cost materials and yet provides a spectacular view of the heavens. Dobsonians are now commonplace in the world of amateur astronomy and are even sold commercially. John loved looking up at the sky and being dazzled by what he saw, and the Dobsonian is a living legacy of his passion and commitment to bring that sense of wonder to millions.

John passed away earlier this year at the ripe old age of 98. He's remembered fondly by many, including the San Francisco amateur astronomy community where he was a fixture for many of his years as a sidewalk astronomer. I only met him on two occasions, but as is the case when you brush with greatness, you know that this person is unique and special in a deep way and you come away from that encounter with a feeling that something greater was before you. I stand in awe and respect for John and am glad to be an astronomy evangelist, inspired in part by the pioneering work he did for all people on the planet.

Moon and Winter Stars and Star Clusters

Moon visits the Winter Circle

The March evening sky features the bold constellations and bright stars of Orion, Gemini, Taurus, Canis Major and Canis Minor. Jupiter is currently occupying a prominent position and this week the Moon passes through this rich part of the sky, enhancing the view with its close encounters with stars and star clusters. On March 7th the Moon will be passing through the Hyades star cluster and two days later through the band of the Milky Way between Orion and Gemini. If the weather permits, take in the view and watch the Moon make its grand procession through the Winter Circle. Binoculars will enhance the view.

Image courtesy of Sky & Telescope.

KFOG Broadcast - February 25, 2014

Today's show with Greg and the Morning Show team at KFOG included a recap of Comet ISON's ill-fated flyby, discussion about the winter skies and magnificent Jupiter, the Vernal Equinox, and upcoming Star Parties on Mt. Tamalpais. Click here to listen.

King of the gods (and the night sky): Jupiter

Jupiter and Winter Circlet

I've been enjoying Jupiter this winter. Jupiter is the most obvious and brilliant object in the night sky after sunset. It dominates the already spectacular winter sky, outshining the bright stars of Orion, Canis Major, Taurus and Gemini, and adding to this bright and busy part of the night sky. The attached diagram shows the bright "Winter Circlet" and the location of Jupiter among the stars of this distinctive circle of stars.

Jupiter is brilliant to the naked eye, but with some magnification becomes even more impressive. This article in Sky & Telescope provides but a few of the highlights to look for if you point binoculars or a telescope at Jupiter. It's marvelous to look at, even if you can only spot the four Galilean moons. But with stronger optics and a clear sky you can see the equatorial bands that stretch across the surface of the planet. And with even more magnification and excellent skies you can see the Great Red Spot. So much to look for in an object that is unmistakeable even in the brightest of city settings. Stop and take a look tonight for Jupiter -- you can't miss it.

Image courtesy Sky Safari.

Dark Universe at the California Academy of Sciences

Over the past few years since the new Morrison Planetarium has opened, the California Academy of Sciences has used the state-of-the-art projection system at the Morrison to present amazing shows, scientifically accurate portrayals of the universe that include travel across vast regions of the cosmos using the latest research and findings from science and the latest in digital projection technology. The results are stunning visual experiences that relate some of the most complex and sophisticated concepts in science and bring the viewer face to face with these realities.

"Dark Universe" is the latest in a series of shows specially designed to take advantage of the Morrison’s projection system. The most recent shows have been created by the Hayden Planetarium and sometimes co-created with the Cal Academy. Dark Universe has credits that span the scientific community for the depth and breadth of visuals and scientific discoveries that are portrayed, an effort to create something that truly reflects the leading edge of our collective knowledge of the universe. The show focused on the most significant cosmological idea and astrophysics question that is being researched, to understand the nature of dark matter and dark energy, the two unknown materials that represent 95% of the “stuff” of the universe. 

Dark Universe appropriately addresses the rapidly increasing knowledge of our universe from the period of Edwin Hubble at Mt. Wilson observatory in the 1920s to the present era of research and discovery of the deepest regions of the universe. Hubble and his contemporaries established visual proof of the theories of galactic evolution and validated that the Milky Way was but one of an extraordinary number of galaxies in the universe, and did so via the concept of redshift, detecting quasars that were in such fast motion that their redshifted spectra proved that the distance to the Andromeda Galaxy in particular was farther than anything seen before in the Milky Way. Starting with that evidence and with the concept of redshift, astronomers over the past century have shown with increasing levels of precision that in fact everything in the universe appears to be expanding and based on mass and gravitational measures, the rates of expansion were not explained by the data they were measuring. "Dark Matter" and "Dark Energy" became the two needed elements to fully describe the physical phenomenon being measured in the cosmos. Yet our current (2014) techniques for measuring these impacts are still not sufficiently calibrated to reveal the true underlying physics and reality of dark matter and dark energy. 

Dark Universe provides highly accurate and visually engaging imagery, one of the hallmarks of the shows at the Morrison Planetarium. The graphics are quite advanced and bring us visuals that were unattainable even just a few years ago. The images are rich with scientific findings from many different missions and research teams (as the lengthy credits made clear), and I believe that the average viewer of Dark Universe will be as impressed as the scientifically-savvy viewer, and will come away with new knowledge and understanding of the cosmos. 

I highly recommend that anyone with interest in science and astronomy see this impressive show. The museum itself is always worth a visit for all of the richness and science it presents, and the Morrison is an excellent space in which to experience Dark Universe. Enjoy!

New Moon and Mercury at Dusk

Mercury and a Young Moon

Elusive Mercury springs into view as January comes to an end, emerging in the glare of dusk this week. The very thin crescent Moon emerges at the same time, and a careful observer with a clear western horizon (and a good pair of binoculars) will have a lovely sight to enjoy. I enjoy seeing the stars and Moon emerge from the glare of the sunset, and when I have a clear view of the sky to the west after sunset I also look backwards to experience the Belt of Venus as it rises on the opposite horizon and envelops the eastern horizon.

Old Moon at Dawn

Old Moon at Dawn

The early morning sky this week features an old Moon fading each day into the sunrise, passing landmarks in our sky as it fades. The Moon follows a path across the sky that parallels the planets, so there are frequent encounters between the Moon and planets, and on the 25^th that features the planet Saturn, not positioned in the east before sunrise. Saturn is gradually moving from the constellation Libra into Scorpius over the next few years, but the Moon makes that same move across the sky in a few days, passing by the bright orange heart of the Scorpion, Antares, one of the biggest stars in the entire galaxy.

You will need a good eastern horizon to see the fullness of Scorpius and the Moon’s path on the 26^th and 27^th but if you are up early you will have a treat seeing these bright objects shining in the morning darkness.

Crescent Moon and Crescent Venus

Two Crescents

The evening sky features two crescents this week, that of the waxing Moon and waning Venus. The Moon's phases are quite familiar to all, but Venus goes through similar phases for similar reasons, and we can observe it from more than just the 'full' phase as we do with outer planets such as Jupiter and Saturn. Venus waxes and wanes like the Moon. This week as it comes close to inferior conjunction, it will resemble the Moon when viewed through a telescope or binoculars. You'll need a clear and low western horizon to see this view shortly after sunset.

More details on EarthSky: http://earthsky.org/space/as-2014-begins-venus-a-thin-crescent-in-bright-twilighthttp://earthsky.org/space/as-2014-begins-venus-a-thin-crescent-in-bright-twilight

Image courtesy of Sky & Telescope.