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 NASA mission surfs through waves in space to understand space weather
25.07.2017 | NASA/Goddard Space Flight Center

nachricht A new level of magnetic saturation
25.07.2017 | Georg-August-Universität Göttingen

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: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA mission surfs through waves in space to understand space weather

25.07.2017 | Physics and Astronomy

Strength of tectonic plates may explain shape of the Tibetan Plateau, study finds

25.07.2017 | Earth Sciences

The dense vessel network regulates formation of thrombocytes in the bone marrow

25.07.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>