Astronomy Picture of the Day 7-20-03

NASA ^ | 7-20-03 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2003 July 20

An Ion Drive for Deep Space 1
Credit: New Millennium Program, JPL, NASA

Explanation: Space travel entered the age of the ion drive in 1998 with the launch of Deep Space 1, a NASA mission designed primarily to test new technologies. Although the ion drive on Deep Space 1 provided acceleration much smaller than we feel toward Earth, it gradually gave the spacecraft the speed it needed to travel across our Solar System. The propulsion drive worked by ionizing xenon atoms with power provided by large panels that collect sunlight. As these ions were expelled by a strong electric field out the back, the spacecraft slowly gained speed. Pictured above, hot blue ions emerge from a prototype drive that was successfully tested at JPL in 1997. Deep Space 1 successfully zoomed past asteroid 9969 Braille in July 1999 and then Comet Borrelly in September 2001, then obtaining the most detailed photograph ever taken of a comet nucleus. The spacecraft was retired in December 2001

[petuniasevan]

Remember Deep Space One? I don't remember a lot of publicity about this craft. It did get close to Comet Borrelly. The timing was bad, though; it was September 2001. Below is an image of the comet taken on 9-25-01.

For details of the mission conclusion, go to this JPL PDF File

[petuniasevan]

[petuniasevan]

Bit by bit I'm adding to the new pages. Click on the pic.

[petuniasevan]

HAPPY BIRTHDAY!

[RightWhale]

Remember Deep Space One?

This technology is the same technology that will be used in asteroid mining. Of course the results of the mission are entirely satisfactory to future asteroid miners.

[Capitalism2003]

curious...How fast can this thing go?

[petuniasevan]

The ion propulsion system on Deep Space 1 carried about 81.5 kilograms of xenon propellant, and it took about 20 months of thrusting to use it all. It increased the speed of the spacecraft by about 4.5 kilometers per second, or about 10,000 miles per hour. This of course was in addition to the speed imparted by the launch into space, and any and all "slingshot" gravity assist maneuvers.

Under the circumstances for which ion propulsion is appropriate, it can push a spacecraft up to about ten times as fast as chemical propulsion. Because the ion propulsion system, although highly efficient, is very gentle in its thrust, it cannot be used for any application in which a rapid acceleration is required.

Missions to the Moon wouldn't use this technology, for example. Neither would manned missions to Mars. It would be in the future Mars-bound astronauts' best interest to get to Mars ASAP.

[graycamel]

Thanx for the birthday greeting. Oh, I forgot to call our sister and wish her the same thing. I'm online now at home.

[petuniasevan]

I was on the night shift when you replied.

I updated the ancestry chart and emailed you a new invite to see it. Thanks for the info...

[graycamel]

Thanx. I thought you didn't get my email. I saw the ancestry chart, or at least part of it. You have stuff I don't have, along with things I need to correct. I have to be in class in 6 hours so I have to go, bye.