Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Arizona Telescopes Will Focus On Pluto March 18

15.03.2007
Telescopes from Wyoming to Mexico City and from California to central Texas will point at Pluto as the dwarf planet occults a star in the Sagittarius constellation next Sunday.

University of Arizona astronomers will host colleagues from Paris Observatory, the Massachusetts Institute of Technology and Lowell Observatory at UA telescopes for the not-to-be-missed event.

Arizona has a special tie to Pluto: Astronomer Clyde Tombaugh was working for Lowell Observatory in Flagstaff when he discovered the ninth planet in 1930. Tombaugh was the only American ever to discover a planet in our solar system. The International Astronomical Union ignited public and scientific controversy last August when it downgraded Pluto's status to a dwarf planet known as number 134340.

But whatever you call it, the object interests planetary scientists.

"Occultations are the only way we can monitor the atmosphere of Pluto from the Earth," said Professor William B. Hubbard of UA's Lunar and Planetary Laboratory, who is coordinating the UA campaign to observe the Pluto occultation.

Not only are the observations important to scientists studying Pluto's atmosphere, Hubbard said, they're important to NASA's $620 million New Horizons spaceprobe, which just flew by Jupiter and is on target to reach Pluto and the Kuiper belt in 2015. Previous observations of Pluto occultations have yielded surprising findings about Pluto's changing air pressure, for example, Hubbard said, "so it's going to be important to keep track of what Pluto is doing until the spacecraft gets there."

An occultation is like an eclipse. Just as the moon casts its shadow onto Earth when it passes directly in front of the sun, planets cast their shadows onto Earth when they pass directly in front of a star. Hubbard, Bruno Sicardy of the Paris Observatory and Faith Vilas, who is now director of the MMT Observatory, discovered Neptune's rings in the 1980s, before Voyager detected them, from ground-based observations made during a Neptune occultation.

In past decades, astronomers could typically expect a Pluto occultation only every five to 10 years, Sicardy said. But now Pluto is moving in front of the Milky Way, and astronomers may see one or two Pluto occultations a year because of the abundance of background stars.

"But even though there are now more than one of these events per year, we can't count on seeing them all because of cloudy weather, or because Pluto's shadow falls on Earth where there are no observatories," Sicardy said.

"This time, the event is observable by a region of the world populated with great telescopes -- the southwestern United States," Sicardy said. "To observe this in Arizona is like closing a big loop after more than 70 years. It's kind of like celebrating Pluto's discovery," he added.

Pluto has a diameter of 2,775 kilometers, or about 1,400 miles, and is almost 40 times farther from the sun than the Earth is. It will pass in front of the star in Sagittarius at 4 a.m. Arizona time (11 Universal Time) on Sunday, March 18. The occultation will last six minutes -- about 3 times longer than typical Pluto occultations -- giving telescopes as small as 50 centimeters (20 inches) time to record the event.

If the telescope is aligned in the exact line of sight with the star when Pluto eclipses the starlight, its lucky astronomers might see the "central flash" phenomenon. They would see a sudden brightening, a flash, while entirely in Pluto's shadow. That could give them important information on the shape of Pluto's atmosphere or its winds, as well as a thrill.

All the visible light cameras are fast readout cameras with good time resolution, said Lunar and Planetary Laboratory scientist Steve Larson. He'll observe with the 61-inch Kuiper Telescope in the Santa Catalina Mountains north of Tucson. "This will help provide accurate timings of ingress, egress and a central flash if we are situated right," he noted.

Participating UA astronomers and telescopes include:

? The UA/Smithsonian Institution's 6.5-meter (260-inch) MMT on Mount Hopkins. Steward Observatory astronomers Donald W. McCarthy and Craig Kulesa will use a wide-field infrared camera called "PISCES" that may spot clouds or haze if they exist in Pluto's atmosphere. At the same time, Susan Kern and Michael Person of MIT will use a "POETS" camera loaned by Lowell Observatory to observe at optical wavelengths. POETS is an acronym for Portable Occultation Eclipse and Transit System. http://www.mmto.org/

? Bruno Sicardy will use a camera from his Paris Observatory on the 90-inch (2.3 meter) Bok Telescope on Kitt Peak. His visible light camera takes 10 frames per second. The Bok Telescope is the largest operated soley by the UA Steward Observatory. http://james.as.arizona.edu/%7Epsmith/90inch/90inch.html

? Catalina Sky Survey Director Steve Larson of UA's Lunar and Planetary Laboratory and Thomas Widemann of the Paris Observatory will observe with Steward Observatory's 61-inch (1.6 meter) Kuiper Telescope in the Santa Catalina Mountains north of Tucson. http://james.as.arizona.edu/~psmith/61inch/

? Rick Hill of UA's Lunar and Planetary Laboratory and Henry Roe of Lowell Observatory will use UA's 60-inch (1.5 meter) telescope on Steward Observatory's Mount Lemmon site. http://james.as.arizona.edu/~psmith/60inch/

Contact Information

William B. Hubbard 520-621-6942 hubbard@lpl.arizona.edu
Donald W. McCathy 520-621-4079 dmccarthy@as.arizona.edu
Steve Larson 520-621-4973 slarson@lpl.arizona.edu
Richard Hill 520-621-4077 rhill@lpl.arizona.edu
Bruno Sicardy http://www.lesia.obspm.fr/~sicardy/
Thomas Widemann http://www.lesia.obspm.fr/~widemann/
Related Web sites
6.5 meter MMT Observatory - http://www.mmto.org/
90-inch Bok - http://james.as.arizona.edu/%7Epsmith/90inch/90inch.html
61-inch Kuiper Telescope- http://james.as.arizona.edu/~psmith/61inch/
60-inch Mount Lemmon Telescope - http://james.as.arizona.edu/~psmith/60inch/

Lori Stiles | University of Arizona
Further information:
http://uanews.org/science

More articles from Physics and Astronomy:

nachricht Climate cycles may explain how running water carved Mars' surface features
02.12.2016 | Penn State

nachricht What do Netflix, Google and planetary systems have in common?
02.12.2016 | University of Toronto

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>