Philosophy of Science Portal: telescopes

Showing posts with label telescopes. Show all posts

Saturday, April 27, 2013

Comfort, no comfort using a telescope

Monday, March 25, 2013

Death Warrant for the Hubble Telescope

"Hubble has 3 more years to make amazing discoveries, NASA says"

Karen Kaplan

March 23rd, 2013

Los Angeles Times

Scientists and space junkies got some good news from NASA on Friday: The space agency announced it would keep the Hubble Space Telescope in operation through at least April 30, 2016.

The three-year extension will cost NASA $76 million, according to the announcement. Hubble is operated by the Space Telescope Science Institute in Baltimore through a contract with the Assn. of Universities for Research in Astronomy.

Launched in 1990 from the shuttle Discovery, Hubble has contributed to many scientific breakthroughs. My personal favorite is the 1998 discovery that the universe is expanding at an accelerated rate, pushed apart by a mysterious force called dark energy. Cosmologists deduced this by measuring the strength of light from dozens of distant type 1a supernovae and realized that these exploding stars were farther away than had been expected. The scientists behind this discovery (including my college friend Adam Riess) won the 2011 Nobel Prize in Physics.

A measurement of the Hubble constant. This is a number that takes the speed at which a distant galaxy appears to be receding from us and compares it to its actual distance. If you know this, you can figure out how fast the universe is expanding – and thus, how old it is. In 1999, a team of astronomers used Hubble to figure out that the universe is between 12 billion and 14 billion years old. In 2002, another group narrowed the range to 12 billion to 13 billion years. (This week, researchers using the European Space Agency’s Planck space telescope came out with a new estimate of 13.8 billion years based on measurements of the cosmic background radiation, a remnant of the Big Bang.)

How galaxies evolve. The telescope has zeroed in on a tiny region of space known as the Hubble Deep Field, which contains galaxies that were born when the universe was still very young. By examining these smaller galaxies – some as old as 10 billion years – scientists have found important differences between their structures and the spiral and elliptical galaxies near the Milky Way, which are younger. The observations have led scientists to theorize that these early galaxies became the building blocks for the ones that came after, perhaps through mergers and other collisions.

Confirming the existence of supermassive black holes. Hubble’s observations of dozens of galaxies have convinced scientists that such black holes are common in the centers of galaxies, and that their mass is proportional to the mass of the bulge of stars in a galaxy's middle.

Figuring out how planets are formed. Scientists had believed that planets – including those in our own solar system – formed out of the disk of dust and other material that surrounded young stars. In 1994, Hubble provided visual evidence to support this theory, observing that such disks were common around young stars in the Orion Nebula.

Detecting the atmosphere of an exoplanet. When a Jupiter-like planet passed directly in front of its home star, the light from the star was filtered by the planet’s atmosphere. By analyzing the resulting changes, scientists were able to figure out the composition of the exoplanet's atmosphere.

Though still going strong after nearly 23 years, Hubble has a replacement on which scientists are working hard. The James Webb Space Telescope will have a mirror that’s six times bigger, with more than 100 motors to focus it. The new telescope is way over budget and way behind schedule, but NASA officials expect it will launch in 2018.

For a “brief” history of how Hubble came to be, check out this write-up from NASA. The story begins way back in 1946.

Tuesday, March 13, 2012

Deceased--Tom Johnson

Tom Johnson
1923 to March 13th, 2012

Telescope visionary Tom Johnson poses with one of his early Celestron Schmidt-Cassegrain telescopes.

Johnson's first really ambitious creation graced the cover of the March 1963 issue of Sky & Telescope.

Tom Johnson, 1923 – 2012

Thomas J. Johnson, the creator of the modern Schmidt-Cassegrain telescope and the founder of Celestron, died early this morning (March 13, 2012), according to Celestron president and CEO Joe Lupica. Johnson was 89.

March 13th, 2012

Sky & Telescope

He ranked among the most important figures shaping the last half century of amateur astronomy.

Johnson was in his early 30s when, in 1955, he used his World War II experience as a radar technician, and postwar employment in the electronics industry, to establish a company called Valor Electronics. Based in Gardena, California, Valor made various components for military and industrial customers, and by the early 1960s it had expanded to roughly 100 employees.

As Valor was growing, so too was Johnson’s own interest in amateur astronomy. After first purchasing 4-inch and later a 10-inch Newtonian reflector, Johnson then headed down a path followed by many amateurs of the day and turned to the hobby of telescope making. The first scope he made was an 8-inch f/4 rich-field Newtonian, soon followed by a 12-inch Cassegrain. Meanwhile, in 1960 he established an "Astro-Optical" division of Valor.

His next telescope project demonstrated that his telescope-making talent and energy would be truly formidable. This scope was a highly unconventional 18¾-inch Cassegrain, made to be transportable. To reduce the weight of the 3-inch-thick primary mirror, Johnson had a ribbed pattern sandblasted into the back of the glass blank. Six months and about $1,000 later, he had a fork-mounted scope that could be disassembled and packed into a car in about 15 minutes.

On July 28, 1962, he hauled the scope to the parking area atop Mount Pinos for its public debut at one of the Los Angeles Astronomical Society’s star parties. It made a big impression among the group’s advanced amateurs, who examined it in detail. The telescope was so noteworthy that it became the cover story of Sky & Telescope's March 1963 issue.

But it was another S&T article that prompted Johnson to change history. As he was finishing the 18¾-inch scope, Donald Willey published a seminal analysis of Cassegrain telescope designs in the April 1962 issue. Johnson was intrigued by the excellent off-axis optical performance of the Schmidt-Cassegrain design. Based on his experience building the 18¾-inch scope and a plan to use optics made to order by Perkin-Elmer Corporation, Johnson took the bold step of advertising a 20-inch multipurpose Schmidt-Cassegrain telescope, called the "Celestronic 20," in S&T’s January 1964 issue.

The Astro-Optical Division name quickly morphed to Celestron Pacific, a division of Valor. By December Valor was dropped, and Celestron’s ad introduced pictures of 4-, 6-, 10-, and 22-inch Schmidt-Cassegrain telescopes as well as mention of a 36-inch. But most of Celestron’s sales were for the 10-inch, which cost about $2,000 when outfitted with basic accessories.

Despite his initial arrangement with Perkin-Elmer, Johnson was soon making his own Schmidt-Cassegrain optics. A breakthrough came early on when Johnson created a method for mass producing the telescopes’ optically complex corrector plates. For this and other contributions to optics, Johnson was later awarded the Optical Society of America’s David Richardson Medal; he was one of only a few non-Ph.D. optical engineers to ever receive the honor.

In the late 1960s, Johnson and his colleagues speculated that the sweet spot of the market would be for a compact, quality 8-inch portable Schmidt-Cassegrain costing around $1,000. And unlike most telescopes of the day, it should be as photography-friendly as the technology of the time allowed. Johnson returned to the drafting table, and what emerged was the $850 “classic C8,” first advertised in S&T’s June 1970 issue. With a radically new orange and tan motif, the C8 was an overnight hit. It set the pattern for all the amateur Schmidt-Cassegrains that would follow in the coming decades from Celestron, its competitor Meade Instruments, and others.

Writes Celestron's president and CEO Joe Lupica: "Tom's innovative, pioneering spirit created a revolutionary method of mass producing an affordable Schmidt-Cassegrain telescope design, which allowed millions of amateur astronomers to pursue their passion for astronomy. Other notable achievements include a 1978 David Richardson Medal from the Optical Society of America, a 1993 Bruce Blair Medal from the Western Amateur Astronomers, and a 2009 Lifetime Achievement Award by the Small Telescope & Astronomical Society. Our hearts go out to Tom's wife and family and to all who were touched by his achievements and innovation."

For more about Johnson's life and how his optical innovations revolutionized amateur astronomy, see The Path of Light. Produced by Celestron two years ago, this 17½-minute documentary features interviews with Johnson and others who grew up using his telescopes.

The Path of Light: Generation of Dreamers

Celestron [Wikipedia]

Sunday, August 28, 2011

Palomar Observatory...1940 footage of construction

Well, here are reels #2 and #3 of some historical footage of the construction of the Palomar Observatory. Unfortunately reel #1 has not been digitized as this time.

The Online Archive of California is an initiative of the California Digital Library.

Historical Note:

Palomar Observatory is located in San Diego County, California, 90 miles (140 km) southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. At approximately 5,570 feet (1,700 m) elevation, it is owned and operated by the California Institute of Technology. Research time is granted to Caltech's faculty and staff members and to research partners, which include the Jet Propulsion Laboratory and Cornell University. The 200-inch Hale reflecting telescope is the principal instrument at the Palomar Observatory. It was built by Caltech with a 6-million dollar grant from the Rockefeller Foundation. The historic 200-inch mirror was manufactured using a Pyrex blank by Corning Glass Works, in Corning, New York, and was shipped by rail to Pasadena for grinding and polishing. It was the vision and effort of the astronomer George Ellery Hale that caused the project to be funded and to go forward. The building of the 200-inch telescope was easily the most famous scientific undertaking of the 1930s. From the beginning, everyone associated with the project realized that the work must be done right or not at all. Every task associated with the Palomar project required a considerable extension of the technology of the day. In an article in the April 1928 issue of Harper's Magazine, George Hale set forth the case for the building of what was to become the 200-inch Palomar reflector. The purpose of this article was to inform the American public about his proposal to construct the largest telescope in the world to answer questions relating to the fundamental nature of the universe. Hale hoped that the American people would understand and support his project. George Ellery Hale died in 1938 and did not live to see the completion of his last and biggest telescope. In June 1948 the 200-inch reflector was dedicated to his memory. The telescope (the largest in the world at that time) saw first light on January 26, 1949, targeting NGC 2261. Russell W. Porter was primarily responsible for the striking Art Deco architecture of the Observatory's buildings, most notably the dome of the 200-inch Hale telescope. Porter was also responsible for much of the technical design of the telescope, producing a series of remarkable cross-section engineering drawings that are considered among the finest examples of such work. Porter worked on the designs in collaboration with many engineers and Caltech committee members. The iconic, gleaming white building on Palomar Mountain that houses the 200-inch Hale telescope is considered by many to be "The Cathedral of Astronomy."

You can download or view at...

Internet Archives

Enter "Palomar Observatory" in the blog's search engine for more material.

Sunday, July 17, 2011

Cheap telescope advertisements

[Click to enlarge and read.]

Tuesday, May 26, 2009

6 years later and Mount Stromlo Observatory reopens

Perhaps you remember the terrible Australian fires of 2003 that demolished most of the Mount Stromlo Observatory complex.

On July 13th, 2003 Penny Sackett, Director of the Research School of Astronomy and Astrophysics, wrote:

The fires destroyed much of our infrastructure, but left our most important asset intact - our people,....

The day after fires, we committed to restoring Stromlo and its network of facilities as a pillar of Australian science.

Three weeks after the fires, our staff were back at work on the mountain, working in two office buildings which were largely undamaged.

We can not and we should not reconstruct a carbon copy of the old Stromlo. This new design is overwhelmingly oriented around meeting the needs of staff, students and visitors - while also ensuring Stromlo retains its status as an internationally important observatory.

For decades, Stromlo and Siding Spring have been operated as integrated observatories, combining the virtues of a control base close to ANU, close to the nation's capital and accessible to the community with a primary observation base offering optimal astronomical and climatic conditions.

The new design retains telescopes and the research hub at Stromlo, but provides even stronger integration with the University’s Siding Spring resources, ultimately providing a more powerful research facility for Australia.

PLANS UNVEILED FOR THE NEW STROMLO

Part of Mount Stromlo Observatory has been rebuilt.

"Eye of Mount Stromlo rises from the ashes"

by

Yuko Narushima

May 26th, 2009

The Sydney Morning Herald

UNRAVELLING the mysteries of the skies will be made easier for scientists worldwide by something of a $13 million phoenix.

A giant telescope was unveiled yesterday, an improvement on equipment lost to Canberra's bushfires six years ago.

The Skymapper is the country's first new optical research telescope in 25 years. It will be used to create a digital map of the southern skies, using detailed pictures taken over the next five years.

The telescope will be based at Siding Spring Observatory near Coonabarabran in NSW and research will be shared freely with scientists overseas via the internet.

The Minister for Science and Research, Kim Carr, said the Skymapper added to Australia's impressive capabilities in astronomy. "It is fantastic to see Mount Stromlo reborn as a centre for internationally significant astronomy after the horror of the 2003 bushfires," he said.

Supporting space science helped people to understand their place in the universe and inspired technology that improved lives, he said.

The lead scientist on the project, Professor Brian Schmidt, said astronomers would use data retrieved by the telescope to make new discoveries. "Everything from dwarf planets like Pluto in our solar system to the first black holes in the universe," he said.

The project began in 2002 when the Australian National University applied for a grant to survey the southern skies using a telescope at Mount Stromlo. Only 18 days after it won the grant, a bushfire ripped through the observatory in a blaze that claimed four lives and destroyed hundreds of homes.

The telescope is also Australia's most sensitive digital camera and can take snaps of a patch of sky 25 times larger than the full moon.

Professor Schmidt called it a "268 megapixel behemoth" with sensitivity 5 million times greater than the human eye.

Space sciences and astronomy projects received $160.5 million in the last Federal Budget, including an $8.6 million pledge to create a Space Policy Unit.

Wikipedia gives this historical outline...

The observatory was established in 1924 as The Commonwealth Solar Observatory. The Mount Stromlo site had already been used for observations in the previous decade, a small observatory being established there by Pietro Baracchi using the Oddie telescope being located there in 1911. The dome built to house the Oddie telescope was the first Commonwealth building constructed in the newly established Australian Capital Territory. Until World War II, the observatory specialised in solar and atmospheric observations. During the war the workshops contributed to the war effort by producing gun sights, and other optical equipment. After the war, the observatory shifted direction to stellar and galactic astronomy and was renamed The Commonwealth Observatory.

The ANU was established in 1946 in nearby Canberra and joint staff appointments and graduate studies were almost immediately undertaken. A formal amalgamation took place in 1957 with Mount Stromlo Observatory becoming part of the ANU.

On January 18, 2003 the devastating Canberra firestorm hit Mount Stromlo (which is surrounded by a plantation pine forest) destroying five telescopes, workshops, seven homes and the heritage listed administration building. The only telescope to escape the fires was the 1868 15-centimetre Farnham telescope.

Saturday, April 4, 2009

"400 Years of the Telescope" on PBS this Friday

Mark your calendar for this Friday night [April 10th] PBS will air "400 Years of the Telescope".

"PBS documentary turns lens on 400 years of telescope"

by

William Loeffler

April 3rd, 2009

TRIBUNE-REVIEW

He filmed the world's most powerful telescopes on five continents. But what really moved Kris Koenig was looking through the primitive instrument that started it all.

During the making of the PBS documentary "400 Years of the Telescope," Koenig visited the Institute and Museum of the History of Science in Florence, Italy. There, he was permitted a peek through the telescope that Galileo used to gaze skyward in 1609.

The instrument that sparked a scientific revolution was a humble, dented cylinder roughly a yard long, with a lens pocked with air bubbles.

"It's impressive that he was able to do the discoveries he did," Koenig says. "It's a very difficult telescope, optically, to look through. He was obviously a very patient man."

"400 Years of the Telescope," which premieres at 10 p.m. Friday on WQED, examines how the telescope altered man's relationship with the universe, from Galileo through the Hubble Space Telescope and beyond.

Aided by the magnifying power of the telescope, Galileo discovered the four largest moons of Jupiter, the phases of Venus and the mountains of the moon. His observations also led him to support Nicolaus Copernicus' theory that the Earth revolved around the sun and not vice versa -- a supposition that eventually led to his conviction as a heretic by the Roman Catholic Church.

"The telescope helped prove that the Earth wasn't the center of the universe," says Tom Reiland, founder and director of the Nicholas E. Wagman Observatory in Deer Lakes Park, "It wasn't even the center of our solar system."

Koenig wrote, produced and directed "Telescope" through his California-based company, Interstellar Studios. He interviewed cosmologists and astronomers from around the world, including Wendy Freedman, director of the Carnegie Institute Washington Observatories, and Chris Corbally, vice director of the Vatican Observatory in Rome. The documentary includes footage of the dormant volcano Mauna Kea in Hawaii, which has 13 observatories.

While it added inestimably to our body of knowledge, the most profound effect of the telescope might have been to show us how little we really know of the universe, Koenig says.

"In reality, '400 Years of the Telescope' is less about the history of the telescope and more about the future of the telescope," Koenig says. "What we are trying to show is that we are as ignorant today in our understanding of the universe as Galileo was 400 years ago."

The documentary explores new theories, such as dark energy, a mysterious force that is accelerating the expansion of the universe, and provides a glimpse of a new generation of super-telescopes, which will have lenses the size of football fields. One is the European Extremely Large Telescope, or EELT. It will most likely be built on a mountaintop in Chile, where atmospheric turbulence is minimal.

"These telescopes that are coming online are 10- to 100-fold better in light gathering and resolution than we have today," Koenig says. "Our view of the universe today will not be our view in 20 years."

Two new survey telescopes that are in the planning stages, the Pannstarr and LSST (Large Synoptic Survey Telescope), will enable scientists to detect asteroids up to 30 years before their possible collision with Earth.

"They'll be online in another five to 10 years," Koenig says.

Galileo built his own telescope after hearing about the new novelty "spyglass," a tube-shabed object that magnified distant objects. That telescope had less power than a pair of modern-day opera glasses, says Peter Machamer, professor of history of philosophy and science at the University of Pittsburgh and an authority on Galileo.

Galileo's discovery that the moon had mountains and craters also disproved Aristotle's theory that matter in space was physically different from that on Earth.

"There's just one kind," Machamer says. "When he looks at the moon, when he finds mountains, this is the support that there's only one kind of matter in the universe."

"400 Years of the Telescope" is part of the International Year of Astronomy 2009, a global celebration of astronomy and its contributions to society and culture. It was created by UNESCO and the International Astronomical Union, the same world body that demoted Pluto from its status as a planet in August 2006.

It is the first PBS documentary to be filmed on 4K digital cinema technology. The process renders a picture with more than five times the pixels of standard high definition.

"400 Years of the Telescope" [PBS]

CARLA BEFERA PUBLIC RELATIONS [many photographs available]

Thursday, March 26, 2009

Just a reminder...the Galileoscope

The Galileoscope

Just a reminder that the Galileoscope is an inexpensive way to celebrate the International Year of Astronomy.

"The Galileoscope, a Telescope for Everyone"

by

Jenny Williams

March 26th, 2009

Wired

I still remember seeing Saturn's rings through a telescope when I was about ten years old. The image of the planet, all white with beautiful rings encircling it, is forever burned into my memory. Most people who have seen such things as children never forget what it felt like to see them for the first time. The awe of seeing something so far away as if it was right in front of you can be life changing. A few months ago, my daughter and I saw Jupiter and its four Galilean moons through my (albeit larger) telescope. I know she'll never forget it, and I won't either.

You can now share this kind of joy and excitement with your little ones for a very reasonable price. It is always a great time for astronomy, but this year is particularly exciting because it is the International Year of Astronomy. As part of their effort to promote the study of the night sky, you can now buy the Galileoscope, a small, inexpensive, high-quality refractor telescope that is as similar as possible to the one Galileo made himself. You can repeat Galileo's observations with help from this educational guide.

Buy a telescope for yourself at $15 plus shipping, or donate one for $12.50 with no shipping charge, however the donation is not tax deductible. The telescope will attach to a standard tripod (not included), and will accept standard telescope attachments (also not included).

The telescope has only a two inch diameter, but for this price, you can bring the joy of astronomy to those who might not be able to afford a larger telescope. With even a telescope of this size, you are able to see sights such as lunar craters, the four largest moons of Jupiter, Saturn's rings and many other objects.

If you have always wanted a telescope but could never afford one, now is your chance to see the night sky close up. The site will begin shipping the Galileoscope in late April.

Galileoscopes

"Constellation" poll

Wednesday, March 25, 2009

Oldest operating public telescope--Mount Lookout

Carol Abbott

Cincinnati Observatory Center in Mt. Lookout

Posthumous accolade of one man's effort to keep a public observatory functioning.

"Sundial brings out astronomer's pals"

by

John Eckberg

March 22nd, 2009

Cincinnati.com

MOUNT LOOKOUT - Dean Regas of Columbia Tusculum figures the late Paul Nohr had a good chuckle during a sundial dedication ceremony Saturday at the Cincinnati Observatory Center.

For most of his life, Nohr was devoted to this Mount Lookout observatory.

He cleaned and rebuilt the two telescopes. He led a drive to save the observatory from the wrecking ball, and today Cincinnati boasts the oldest operating public telescope in the nation: from 1845.

But something was missing at the Paul Nohr Memorial Sundial dedication, and no amount of waiting was going to change that.

"No sun," said 35-year-old Regas. "Paul would have gotten a kick out of that."

This ground level sundial, which has a 50-foot diameter, requires audience participation - and a few rays of sun - to get the time.

It was designed by RWA Architects and found support in donations from businesses and friends of Nohr, a former University of Cincinnati astronomer who died in 2006.

Nohr first came to the observatory in the late 1940s for an astronomy club meeting. His dad drove across town. The boy took weekly trips across the cosmos.

By the time Nohr was an adult, the observatory had fallen into disrepair. Nohr couldn't ignore the place, his wife, Pamela, said. "He loved teaching about astronomy."

And nothing was better than explaining the nuances of the firmament to an awestruck kid. In fact, Nohr wanted to retire from the university to teach children full time.

"I remember when I met him," said Chuck Strubbe, 50, of Hyde Park. "We walked into the observatory. He looked at us and said, 'Here's the telescope - point it at something.'"

"We were like whoa, this telescope was a national treasure."

Nohr knew that telescopes - even antique ones made of wood with lenses from Bavaria - were not museum pieces. They were meant to be viewed not stored.

[The Cincinnati Observatory Center is open to the public on Friday and Saturday nights but reservations are suggested. Children under 18 are admitted for $3; adults, $5. The observatory, on the border of Mount Lookout and Hyde Park at 3489 Observatory Place, has a gift shop on the grounds. Call 321-5186 for reservations or email: observatory@fuse.net.]

Cincinnati Observatory

Saturday, March 14, 2009

"Telescope ownership/use" poll

Do you own and use a telescope?

Yes....1
No....1

Surprised by the number of responses. And I know who voted "No". That person should return those 15 cans of Beanie Weenies to the Dollar General and buy this telescope...

Galileoscopes

Thursday, March 12, 2009

Telescopes--ticket to the stars

A good presentation on our relationship with telescopes and the stars.

[These are large screen presentations and thus slip beyond the frame of the template.]

Part 1