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Oakland Teachers Scope Out What Galileo Saw

 

Ben Burress by Ben Burress  November 6th, 2009
37.8148, -122.178

Oakland Unified teachers assembling Galileoscopes at ChabotWhat was it like for Galileo, the first time he put an eye to his telescope to see things in the heavens as never before seen? As anyone who has seen a planet or a star cluster or a nebula—or the Moon—through even a small telescope knows, the sight can be quite breathtaking. For Galileo, it must have been a universe-changing experience….

Through a generous donation by a concerned citizen (concerned that kids today aren't seeing enough of the sky), Chabot just completed a pair of workshops for Oakland teachers that places in their capable hands and in their classrooms "Galileoscopes"—special telescopes designed and manufactured for the 2009 International Year of Astronomy. The Galileoscope is a low cost, simple, but good-quality telescope designed to simulate the power and field of view of Galileo's original telescope, which opened up the universe in such a profound way.

In September and October, a total of 23 Oakland teachers received training, activities, and one Galileoscope each (plus tripod), enabling them to share the experience with their students and, hopefully, spark their imagination and curiosity about the world around us in a way that nothing but astronomy does.

A look through a telescope—any telescope, big or small—does put a spark in the eye and the imagination. At least, that was my experience. Growing up in Oakland back in the 60's, I didn't have access to any small telescopes, but Chabot Observatory was only a couple miles away, and my family often went up on a weekend night for a classroom demo, a planetarium show, and thoroughly enjoyable viewing through the two antique telescopes, Leah and Rachel. Something about the actual light from Saturn or Jupiter or a distant galaxy tickling the receptors in your retina places you out there—or puts those objects directly into your brain.

The Oakland teachers now armed with their Galileoscopes will use these simple but effective tools to show their students the difference between seeing Saturn as a spot of light and Saturn as a disk with "ears" (the appearance of its rings through a Galileoscope), or the difference between Jupiter as a brighter spot of light and Jupiter as a world with a giant storm in its clouds and four smaller "worlds" (moons) in orbit around it, or the difference between the Moon as a disk with light and dark areas that make interesting shapes in our imaginations and the Moon with mountain ranges, vast plains, thousands upon thousands of craters, and shadows stretching across the landscape.

By the way, Galileoscopes can still be ordered, through the Galileoscope website, for a short time still, in case you're interested in getting your toe into the door of a much bigger universe….

Web of Stars

 

Ben Burress by Ben Burress  October 23rd, 2009
37.8148, -122.178

Students in Cork, Ireland interacting live via Skype with Chabot
during real-time observing session.
What do Chabot's 36-inch telescope, Nellie, and a classroom full of 14-year-old girls in Cork, Ireland have in common? In a few words, the International Year of Astronomy and the Web of Stars!

Wednesday morning around 1:00 AM, Chabot staff astronomer Conrad Jung and I fired up the systems in the 36-inch observatory and made a Skype video call to the Blackrock Castle Observatory in Cork, Ireland. Staffers Frances McCarthy and Alan Giltinan answered—it was 9:00 AM for them, and Frances had already been up four hours to prepare for our premiere session of Web of Stars. A bus-load of girls from a local school were on their way through the downpours of rain Cork was experiencing at the time.

On our end, everything technological was working fine: Nellie, our 36-inch telescope, was stoked, motors humming and ready to drive us to faraway celestial locales; computers were singing (in their own particular way), and the webcam-Skype interlink was green. The webcam view nicely framed the telescope, making a great background for the session.

A little after 2:00 AM PDT, the girls from North Presentation Secondary School rolled into the classroom, and there was a great deal of excitement. Eight or nine of them immediately descended upon the microphone and webcam and started chirping "helloes" and "hi's" at us across the 5,000 mile gulf (what's an ocean and a continent to get in the way of the Internet?).

After the greeting buzz died down, and the girls' teacher and the facilitators at Blackrock Castle got them to their computer stations, the morning's work began….

"We regret," Conrad and I had to inform them, "that the weather at Chabot is damp, and we're completely fogged out." This was a disappointment, of course, but we had a Plan B lined up in the event of bad astronomy weather. From Conrad's archive of astrophotography, we pulled up some un-processed astronomical images from months past and dumped them to our FTP server, where Alan at Blackrock Castle immediately downloaded them to the girls' computers: Comet Lulin, the Andromeda Galaxy (M-31), the Hercules globular cluster (M-13), the Apollo 15 landing region on the Moon, the Great Nebula in Orion (M-42), and the Ring Nebula (M-57) were the fare for the session.

With the astro-image processing software Salsa-J, the Cork girls proceeded to process the images—taking each set of three color channel (red, green, blue) black and white images and combining them into composite full-color images. Throughout the 2-hour session, the girls broke away from their computers two and three at a time to come to the microphone and chat with Conrad and I—we were even treated to a song or two from the girls, one by the entire class: On the Banks of My Own Lovely Lee.

The Web of Stars program was conceived of by Blackrock Castle Observatory, and Chabot became the partner observatory through proximity to San Francisco, which is a sister city of Cork. In Ireland, classrooms competed over the summer to earn one of the six pilot observing sessions with Chabot, and the program will unfold from October through March with one session each month.

Though we had to resort to our bad weather Plan B ("B" for "bad" weather) for our kick-off session, the A plan ("A" as in "actual active astronomy") will be for us to acquire and image objects with Nellie from lists of targets sent to us by the students in Cork, and deliver them in real time to the classroom at the Castle, where they will conduct the image processing and measurement activities in lock step.

Please wish us and the students in Cork good weather!

Jumpin' Jupiter! Where Did the Galileans Go?

 

Ben Burress by Ben Burress  September 11th, 2009
37.8148, -122.178

Three views of Jupiter before, during, and after the disappearing act by its four large moons. Credit, Conrad Jung, Chabot Space & Science CenterNow you see them, now you don't! Had Galileo spied the planet Jupiter with his telescope 400 years ago on a night such as a couple of Thursdays ago, would the history of modern astronomy have unfolded any differently? Would Jupiter's four large "Galilean" moons have been named so in his honor? Would we still think that everything revolves around the Earth?

What am I talking about? About a week ago a relatively rare alignment of Jupiter and its four Galilean moons—Io, Europa, Ganymede, and Callisto—made for a brief time in which the moons disappeared, hidden behind and in front of their massive parent planet. For that brief time, Earth, Jupiter, and all four Galileans coincided on a nearly perfect line.

The event took place late in the evening on September 2nd, a little after 10:00 PM. Ganymede (the Solar System's largest moon) and Europa (the "snowball" with the probable deep liquid water oceans under its icy crust) crossed in front of Jupiter's disk, and the other pair, Io (the volcano moon) and Callisto passed behind it.

It's not uncommon for one of these moons to be out of view for a time when you aim a telescope at Jupiter. Even Galileo, on his first telescopic look at Jupiter, saw only three of them.

The disappearance of two or three of them at once is more rare, however, and a vanishing act by all four only happens a few times in a lifetime—every century, there are about 20 such alignments. The last such event prior to last week's was back in the 1980's; the next one won't happen until 2019. This event was not only observed on September 2nd by Chabot Space & Science Center astronomer Conrad Jung, but also in 1913 by then Chabot Observatory director Charles Burckhalter.

When Galileo took his newly made telescope and became the first person in history to look at Jupiter through the new invention, he saw three star-like points of light positioned around Jupiter, roughly on a common line that passed through the planet. At first he thought they might be stars, but on subsequent nights he observed that not only did these "stars" follow Jupiter's own movement through space, they changed position relative to each other. This led to Galileo's hypothesis that these were satellites in orbit around Jupiter.

The rest is history (oh, and lifelong house arrest for Galileo for suggesting that there was something in the Universe that didn't revolve directly around the Earth…).

I'm sure that if Galileo had first looked at Jupiter on one of these rare nights and saw no moons, he would certainly have discovered them the next time he looked at Jupiter—so maybe it wouldn't have changed the unfolding of historical events much. But I wonder which would have been more surprising to him: seeing the moons on the first look, or observing them to appear out of nowhere after the initial observation of a solitary Jupiter….

Crab Nebula: Awesome Beauty From Destruction

 

Ben Burress by Ben Burress  August 28th, 2009
37.8148, -122.178

The Crab Nebula as seen through Chabot Space & Science Center’s 8-inch refracting telescope, Leah. Image: Conrad Jung, Chabot Space & Science CenterWhen asked what got me interested in astronomy, the stock answer I offer is my childhood experience going to Chabot Observatory and looking through the telescopes—and I'm sure that had a great deal to do with it. But, if I want to give an even shorter answer, I just say, "Crab Nebula!" and walk away….

What's the Crab Nebula? Astronomy enthusiasts are very familiar with this celestial object, or at least become so very quickly after entering the world of space. It's a supernova remnant—a torn and tortured cloud of gases expanding outward into space, the aftermath of a supernova explosion that happened almost a thousand years ago in the constellation Taurus. In fact, as I write this blog, the age of the Crab Nebula is exactly 955 years and 40 days.

How do we know with such precision when this former star went supernova? The answer, as always in science, is careful observation! The explosion of the star was witnessed by Chinese and Japanese astronomers—and possibly sky watchers of the American Southwest—who carefully observed and recorded the event. The explosion took place on July 4th, 1054 CE.

Seven hundred years later, a century after the invention of the telescope, the Crab Nebula was discovered in the same spot—first in 1731 by John Bevis, then again by Charles Messier in 1758 (August 28, in fact—the date of this blog posting!). Messier ran across it while searching for Halley's Comet, and at first mistook it for a comet. This was the reason that he began compiling his famous Messier catalog of "fuzzy" objects: a wall of mug shots of unusual suspects that resembled, but were imposters of, comets. He began his catalog with Messier 1 (M1), the Crab Nebula.

Messier 1 got its nickname of the Crab from a drawing made by observer Lord Rosse in 1844.
Today, the Crab Nebula is an expanding cloud of gas and some dust spanning 10 light years, or 60 trillion miles. The cloud is still expanding at a speed of about 1,800 kilometers per second—a speed that would get you to the Moon in just under 4 minutes! At its center is the collapsed remnant of the dead star's core, which has become the incredibly small and dense object known as a neutron star.

So why did the Crab Nebula spark my interest in astronomy? I have a specific memory of being at a summer camp and engaging in a craft activity where we cut out the pictures from a bunch of astronomy calendars and made frames and matting to display them in. I selected a few of my favorite images, which included the Dumbbell Nebula (a planetary nebula), the Veil Nebula (another supernova remnant), and, of course, the Crab. Of all these stunning astrophotos, it was the Crab that stuck the longest in my mind and on my bedroom wall, and impelled me to get my first subscription to Astronomy Magazine, and eventually my first telescope. Sometimes, our lives are guided by stars….

Science Event Pick: Stardust in our Bones

 

Kishore Hari by Kishore Hari  August 15th, 2009
37.871754, -122.260760

David Lindberg, Professor of Integrative Biology at UC Berkeley, and Steve Croft, postdoctoral researcher in the Department of Astronomy at UC Berkeley2009 marks the double whammy for science historians and lovers:  The celebration of the 400th anniversary of Galileo first pointing the new invention of the telescope at the sky and the 200th birthday of Charles Darwin and the 150th anniversary of On the Origin of Species.

How do you connect seemingly separate historical events? Team an astrophysicist and an evolutionary biologist of course. David Lindberg, Professor of Integrative Biology at UC Berkeley, and Steve Croft, postdoctoral researcher in the Department of Astronomy at UC Berkeley will tie these great anniversaries in a unique lecture this weekend.

Starting 14 billion years ago with the Big Bang, Steve will trace the evolution of the universe, from scorching hot gas forming galaxies to the continued birth and death of new stars. David will step in and discuss how the history of our special little planet is inexorably tied to material raining down from space. The water in our oceans, the formation of some organic molecules, and even mass extinctions on this planet have largely been determined by extraterrestrial events. And let's not forget Area 51 (that's a joke!).

Astronomy and Evolution: From the Death of the Dinosaurs to the Stardust in your Bones

When: Saturday, August 15th 11AM – 12 PM

Where: 100 Genetics & Plant Biology Building, UC Berkeley Campus

Cost: Free

Far Out, Man: Measuring Astronomical Distances

 

Ben Burress by Ben Burress  July 3rd, 2009
37.8148, -122.178

Centuries ago the stars were believed to reside just beyond the planets of our solar system.It never fails to astound me how big the Universe is—how far away even the nearest stars are, let alone other galaxies scattered from here to near infinity….

How do we know how far away celestial objects are? This shouldn't be taken for granted, as it's not as straightforward as sounding the depth of the ocean floor with sonar, or determining the range to an object by bouncing radio waves off it and timing the reflection.

In fact, we have "pinged” the nearest celestial objects with radar to determine their distances very accurately. Examples are the Moon and Venus, where round-trip lightspeed travel is measured in seconds or minutes.

Before radar, the scale of the Solar System had to be determined geometrically, by observing events like Venus or Mercury transiting the face of the Sun from different locations on Earth and triangulating. Even this technique requires telescopes, which we've had only four hundred years. Before that, figuring out distances to just about everything except the Moon was mostly guesswork. In fact, it wasn't too many centuries ago that the entire Universe was believed to be not much larger than the Solar System—the Sun and it's nine…excuse me…eight planets—as we know it today.

Once the distance from Earth to the Sun was figured out, that length (the "Astronomical Unit”) in effect became a basic measuring rod for working out distances to everything else, by one means or another.

As Earth orbits the Sun, the direction from which we see stars shifts minutely, and we can observe a small change in a star's position compared to the more distant "background” stars. You can see the same effect by holding a finger in front of your face and looking at it alternately with one eye, then the other.

The geometry of this observation is a simple triangle, whose base is the distance between your eyeballs and whose legs are the lines from each eyeball to your finger. By knowing the length of the base, and observing the change in viewing angle against the background, the length of the legs (distance from your eyeballs) can be calculated.

In the case of Earth and a nearby star, the "eyeballs” are the Earth at two ends of its orbit around the Sun (six months apart) and the "finger” is the star.

But this measuring of distance by "trigonometric parallax," as it's called, only works for the nearest stars, as the minute shift in the star's apparent position diminishes with distance.

As astronomers learned more about the distance to nearby stars, they determined how to relate their temperature and mass to their actual brightness, and it became possible to estimate the distance of many stars by measuring their apparent brightness, with an understanding of how the brightness of light weakens with distance.

To measure the depths of space between us and galaxies far, far away, in which individual stars are indistinguishable from the overall galactic glow, we can turn to certain types of supernovae: individual stars that temporarily shine brightly enough to be observed and measured. Like the flare of a match struck in the dark night, the brilliance of the flash reveals how far away the striker stands.

We have built up our knowledge of the Universe's vastness over the past couple centuries, working out the problem from the near to the far. Even as science and technology have made the world on which we live smaller, it has done exactly the opposite to the Universe….

Reporter's Notes: Crash Landing

 

David Gorn by David Gorn  May 29th, 2009
37.414208, -122.06224

Credit: NASA.

When the LCROSS satellite, nicknamed Centaur, smacks into the south pole of the moon in late October, it is expected to produce a plume of dust 37 miles high, which may be visible from Earth with a good backyard telescope. It will be visible in an arc from Hawaii to Texas.

If you'd like to catch the impact, the Chabot Space and Science Center in Oakland is hosting a Shooting the Moon star party on the night of impact. Morrison Planetarium in San Francisco may host a star-gazing event, as well, but it hasn't been announced yet. And you could check in on other observatories in the Bay Area, as well: Lick observatory in the Santa Cruz mountains, Foothill observatory in Los Altos Hills, Sonoma State observatory in Rohnert Park, and the Fremont Peak observatory in the East Bay.

Not all of them will be open to the public; for instance, Foothill Observatory will be closed to the public, because they’ve been asked to take photographs of the event.

If you know anyone with a 10-inch telescope (that's the diameter of the lens), you can bet that telescope will be lined up to look skyward when the LCROSS probe hits the moon.

If the impact goes well, then the plume above the moon's surface could hover there for hours. It will make its own crater on the moon about 6 feet deep and 30 yards wide, so the plume of dust will not be visible to the naked eye, or even through binoculars.

The exact date, time and even the exact location of the impact have not yet been determined. Keep your eye on NASA's site for more information.

And one aside: This impact will not hurt the moon, or send it off its orbit. That may seem apparent to many people, but NASA Ames officials say those are the most-asked questions about the project.

Listen to the Crash Landing radio report online.


Hubble Gets a New Lease on Space

 

Ben Burress by Ben Burress  May 22nd, 2009
37.7631, -122.409

The Hubble Space Telescope being serviced by Space Shuttle
Atlantis astronauts in May 2009. Credit: NASA
Four hundred years ago, Galileo built his telescope and became the first on record to point the new device (invented the previous year) at objects in the sky. Today (in fact, even as I write!) what has become a symbol for the current state of evolution of the telescope—the Hubble Space Telescope–is being repaired and upgraded by the crew of the Space Shuttle Atlantis…for the last time.

Galileo's telescope had a magnification of only about 27x, allowing him to see that Venus has phases like the Moon, Jupiter has four large moons of its own, Saturn does not appear as a simple disk but has unusual "projections" to either side, and the Milky Way contains far more stars than is apparent to the naked eye. And though these are features that can be seen through the least powerful home telescopes today, Galileo's observations changed the way we look at the universe.

Hubble has done the same thing, but on a modern scale of magnitude. Not a large telescope by the standards of ground-based behemoths like Keck in Hawaii (Hubble's primary mirror is 2.4 meters in diameter), Hubble's "edge" is it's location in space, orbiting the Earth over 300 miles high, outside of our atmosphere. Particularly in its earlier days before ground based telescopes were using adaptive optics techniques to compensate for atmospheric distortion, Hubble's vision on the universe was unparalleled in its clarity.

Here's is a recap of a few of the many big discoveries Hubble has made possible:

Dark Energy: By accurately measuring the distance and velocity of distant supernovae, over a large range of distances, Hubble has refined out knowledge of the rate of expansion of the universe–leading to the discovery that the expansion of the universe is actually accelerating, contrary to what was expected. Scientists suggest the existence of a mysterious "dark energy" throughout the universe that exerts an antigravitational repulsive pressure on the cosmos.

Age of the Universe: Since Edwin Hubble (for whom the Space Telescope was named) discovered that the universe is expanding, astronomers have been trying to determine how long ago the expansion began–how long ago the "starting gun" of the Big Bang was fired, and thus the beginning of the universe. Through precise observations with the Hubble, astronomers in recent years have been able to peg it between 12 and 14 billion years. (Most recently, observations made with the WMAP mission have honed that down to 13.7 billion years, give or take 0.13 billion.)

Supermassive Blackholes: Hubble found the clues that point to the existence of "supermassive" blackholes at the heart of maybe most–or every–galaxy. The Milky Way's own central blackhole has a mass equivalent to four million Suns.

Stellar Dust Disks: Before the first extrasolar planets were actually detected, Hubble observations revealed that flat disks of dust encircling young and developing star systems–aka "protoplanetary disks"–is commonplace. This has given us a glimpse at what our own solar system may have looked like before the planets formed.

It has been seven years since the last Hubble servicing mission, with another servicing scheduled a few years ago cancelled in the wake of the Columbia disaster. Several failing systems will be repaired or replaced this time, and other instruments are receiving upgrades that will make Hubble more powerful than ever in its declining years.

This mission to service the Hubble will be the last. Since NASA is retiring the Space Shuttle fleet after 2010, we will no longer have a space vehicle large enough to carry upgrade and replacement equipment to and from the Hubble. After that, the next new big space-based descendent of Galileo's spyglass will be the James Webb. Stay tuned…

Reporter's Notes: Do-It-Yourself Mini-Satellites

 

Lauren Sommer by Lauren Sommer  May 15th, 2009
37.42444, -122.16714

Cal Poly's CP-4 mini-satellite in orbit. Credit: The Aerospace
Corporation.

It's a classic engineering story – a garage inventor spends years working in isolation, only to produce something that gets the attention of the world. Ok, the CubeSat story may not be quite as romantic, but it does have a lot of the same ingredients.

Professors at Stanford University and Cal Poly created CubeSats – 10 by 10 by 10 centimeter mini-satellites – as enginneering projects to give their students hands-on experience. Compared to standard satellite missions, which can run hundreds of millions of dollars and take years to complete, CubeSat missions are mean to be done cheaply and quickly.

CubeSat is also a standard – a basic blueprint that any university program can use. CubeSats are actually known as "FedEx satellites," since universities can mail them to Cal Poly to arrange a ride into space. They've created launching devices called P-Pods (a box that fits the CubeSats perfectly) so they can piggyback on larger rocket launches. Once the main cargo is deployed, the P-Pod releases the CubeSats into orbit. Depending how high they are, CubeSats can orbit for more than a decade before they burn up in the atmosphere.

What started at universities has spread – NASA, Boeing and other aerospace companies all have mini-satellite programs. Despite the small size, CubeSats are actually able to do valuable research. They can space test new technology, submitting it to all the rigors of space travel like solar radiation and launch stress. Recreating those conditions on the ground can be very expensive.

CubeSats can also gather scientific data. On Tuesday, NASA will be launching Pharmasat, which they hope will be their second nano-satellite in orbit. It will carry yeast samples, and once in orbit will hit them with an anti-fungal to see if their resistance is increased in space. NASA has previously observed that some bacteria are more resistant to antibiotics in space, something that could be dangerous for future human space travel.

You can tune in on Tuesday evening for the Pharmasat launch. Three other CubeSats from Cal Poly and other organizations will also be getting a lift into space.


Listen to the Do-It-Yourself Mini-Satellites radio report online, and see our Web Extra: Mini-Satellites Slideshow.


Producer's Notes: LCROSS Rocket to the Moon

 

Sheraz Sadiq by Sheraz Sadiq  April 7th, 2009
37.4189, -122.063999

A scale model of the LCROSS payload.

Update: On October 9th, 2009 at 4:30AM PDT, the upper stage of the Centaur rocket carrying LCROSS smashed into a crater near the moon's south pole. The LCROSS spacecraft followed close behind, made measurements and took images of the emerging lunar debris. On November 15th, beds of water ice were discovered at the lunar south pole.

With a price tag of 80 million dollars and a little more than two years in the making, the LCROSS spacecraft will begin its voyage atop an Atlas V rocket. Shortly thereafter it will shepherd the upper stage of the rocket in an orbit around the moon to position it in place for a colossal impact that will kick up a cloud of lunar dust forty miles high. The goal is to see if water exists on the moon and if it does, buried deep beneath the lunar soil, accumulating over millions of years of impacts with comets, it would accelerate our efforts to establish a permanent lunar base. Think of it as a rest stop to refuel (oxygen is an essential ingredient of rocket fuel) before arriving at the next closest planetary body, Mars, a journey which takes roughly 600 days, or 200 times longer than a trip currently to the Moon from Earth.

The avid QUEST viewer may recall that we covered the LCROSS mission in the first episode of QUEST back in 2007. A lot has happened since then, including most notably a change in the launch date which at the time of this post was scheduled for May 20th, 2009. Peter Schultz's vertical gun range has been outfitted with some dizzyingly high-tech cameras, which are capable of recording at tens of thousands of frames per second (one can record at one million frames per second) to capture the most minute progressions of the lunar impact simulations performed with the thirty-foot tall vertical gun. The suite of nine instruments aboard LCROSS, known as its "payload", has been mercilessly subjected to thermal, vibration and acoustic testing to make sure they can withstand the effects of launch and the harsh celestial environment. And then there's the spacecraft itself which we weren't able to show you in 2007 because the spacecraft still had to be transformed from a set of designs into a compact, robust structure the size of a small car by a team of sharp, young Northrop Grumman engineers. Moreover, amateur astronomers, armed with telescopes ten inches or more, are now being encouraged by NASA to share their images of LCROSS' historic lunar impact.

One of the most impressive attributes of the LCROSS mission is its rapid turnaround and cost containment which in turn highlight the innovative production model that was essential in making LCROSS a reality. Imagine the spirit of Silicon Valley, with its entrepreneurial zeal and efficiency, fusing with some of the sharpest minds in astrophysics and aeronautical engineering, and you have a glimpse of the unique nature of this small but nimble mission which just may forever change our understanding of the moon and its secrets.


Watch the LCROSS Rocket to the Moon" television story online.


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