APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
If you have the latest JAVA, this applet will show you a good 3D view of the relationship between Earth and Hartley2jumpjack wrote:Why can't we see any tail attached to this comet? Which are Earth and Hartley positions in their orbits?
I can't find any gif animation, and I can't see youtube from this PC.
The Comet is opposite the Sun from Earth, the tail would be going away from us.jumpjack wrote:Why can't we see any tail attached to this comet?
thanks.BMAONE23 wrote: If you have the latest JAVA, this applet will show you a good 3D view of the relationship between Earth and Hartley2
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1 ... ;cad=0#orb
you're welcomejumpjack wrote:thanks.BMAONE23 wrote: If you have the latest JAVA, this applet will show you a good 3D view of the relationship between Earth and Hartley2
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1 ... ;cad=0#orb
Cool, didn't notice it.BMAONE23 wrote:you're welcomejumpjack wrote:thanks.BMAONE23 wrote: If you have the latest JAVA, this applet will show you a good 3D view of the relationship between Earth and Hartley2
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1 ... ;cad=0#orb
you can also designate any other named or numbered object orbiting the sun and see its orbital path
like entering apophis in the search box near the top of the page
(not the Search JPL area in blue though) but next to the line "JPL Small-Body Database Browser"
Exactly one week before the world gets a new look at comet Hartley 2 via NASA's EPOXI mission, observations of the comet by the Arecibo Planetary Radar in Puerto Rico have offered scientists a tantalizing preview.
"It kind of looks like a cross between a bowling pin and a pickle," said EPOXI project manager Tim Larson of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Only it's about 14-thousand-times larger and hurtling through space at 23 miles per second."
Scientists using Arecibo's massive radar dish began observations of Hartley 2 on Oct. 24, just four days after the comet made its closest approach to Earth since its discovery in 1986. (On Oct. 20, the comet came within 17.7 million kilometers, or 11 million miles, of Earth). The observations are scheduled to continue through Friday, Oct. 29.
During the Nov. 4 flyby, the cameras aboard the EPOXI mission spacecraft will get within 700 kilometers (about 435 miles) of the comet.
"Observing comet Hartley 2 from the Earth with radar was like imaging a 6-inch spinning cucumber from 836 miles away," said Jon Giorgini, a scientist at JPL and a member of the Arecibo team that imaged the comet. "Even without all the data in, we can still make some basic assertions about Hartley 2. Its nucleus is highly elongated and about 2.2 kilometers [1.4 mile] long, and it rotates around itself about once every 18 hours. In addition we now know the size, speed and direction of particles being blown off the comet, and we immediately forwarded all this information to the EPOXI team."
Just what a celestial pickle means for the EPOXI mission remains to be seen. Mission engineers and scientists are discussing the new findings and what - if anything - they signify for the upcoming comet encounter.
Along with Giorgini, observations of comet Hartley 2 were led by Arecibo Obervatory's John Harmon, with contributions by Mike Nolan and E. S. Howell.
bystander wrote: Space Radar Provides a Taste of Comet Hartley 2
NASA JPL | 2010-358 | 28 Oct 2010Exactly one week before the world gets a new look at comet Hartley 2 via NASA's EPOXI mission, observations of the comet by the Arecibo Planetary Radar in Puerto Rico have offered scientists a tantalizing preview.
"It kind of looks like a cross between a bowling pin and a pickle," said EPOXI project manager Tim Larson of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Only it's about 14-thousand-times larger and hurtling through space at 23 miles per second."
http://en.wikipedia.org/wiki/Indian_clubs wrote:
A pair of painted late 19th century Indian Clubs<<Indian clubs belong to a category of exercise (and juggling) equipment that was popular in the late 19th century and early 20th century in Europe, the British Commonwealth and the United States. They comprise bowling-pin shaped wooden "clubs" of varying sizes and weights, which are swung in certain patterns as part of an exercise program. They can range from a few pounds each, up to special clubs that can weigh as much as 50 pounds. They were used in carefully choreographed routines where the clubs were swung in unison by a group of exercisers, led by an instructor in the front, similar to modern aerobics classes. The routines varied according to the group's ability and the weight of the clubs used.Click to play embedded YouTube video.
Indian clubs derive their name from the much larger and heavier objects of similar shape traditionally used by martial artists and pehlwani wrestlers in India to train for strength. The practice of swinging such clubs to develop physical fitness was first recorded in ancient Egypt and the Middle East. It was introduced to England by British soldiers who were stationed in India during the 19th century.
They were exceptionally popular during the health craze of the late Victorian era, used by military cadets and well-heeled ladies alike, and even appeared as a gymnastic event in the 1904 and 1932 Olympics. Gymnasiums were built just to cater to club exercise groups. The popularity of the Indian Club waned in the 1920s and 1930s as organized sports became more popular. Regimented exercise routines, like those requiring Indian clubs, were relegated to professional athletes and the military, who had access to more effective and modern strength training equipment. While torches and other sticklike objects have been used in juggling for centuries, the modern juggling club was inspired by the Indian club, which was first repurposed for juggling by DeWitt Cook in the 1800s.>>
http://en.wikipedia.org/wiki/19P/Borrelly wrote:<<Deep Space 1 flew by comet 19P/Borrelly on September 22, 2001. It flew within 2,171 km of the nucleus at 22:29:33 UT. The nucleus is about 4 by 8 kilometers in size and incredibly dark, with an albedo varying from 0.01 to 0.03. Credit: NASA / JPL / Ted Stryk
On September 21, 2001 the spacecraft Deep Space 1, which was launched to test new equipment in space, performed a flyby of Borrelly. It was steered toward the comet during the extended mission of the craft, and presented an unexpected bonus for the mission scientists. Despite the failure of a system that helped determine its orientation, Deep Space 1 managed to send back to Earth what were, at the time, the best images and other science data from a comet.
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Attributes Borrelly Hartley 2 --------------------------------------------------- Aphelion distance: 5.83 AU 5.87 AU Perihelion distance: 1.35 AU 1.05 AU Semi-major axis: 3.59 AU 3.46 AU Eccentricity: 0.624 0.694 Orbital period: 6.8 6.46 Inclination: 30.3° 13.6° Dimensions: 8×4×4 km 2.2×0.7×0.7 km Density: 0.3 g/cm³ Albedo: 0.03 0.028
