Category: Satellites

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This just in from ‘The Sky is Falling’ Department: NASA’s Orbital Debris Newsletter reports that a launch vehicle rocket motor casing was found by ranchers in the Australian Outback during a cattle round-up on a three million-acre pasture property. It was first spotted by Mr. Arthur Taylor who was flying a Cessna aircraft to look for stray cattle. The casing appeared in relatively good condition (see picture above) and did not seem to be very old. Mr. Michael White forwarded numerous photos of the object to the NASA Orbital Debris Program Office, including one with a clear serial number next to the nozzle attachment point. Using the serial number, NASA Kennedy Space Center personnel were able to trace the motor casing to a a specific mission.

The casing came from a Delta 2 rocket used on June 2, 1990 to launch the Indian INSAT-1D geosynchronous spacecraft from the Cape Canaveral Air Force Station, Florida. This solid rocket motor served as the launch vehicle’s third stage which carried the payload from a low altitude parking orbit into a geosynchronous transfer orbit. (If you want to trace it yourself, here are the particulars: U.S. Satellite Number 20645, International Designator 1990-051C), Reentry of the stage occurred a few months later.

This isn’t the first time rocket casings have been found in Australia, and this object joins similar solid rocket motor casings found in Saudi Arabia, Thailand, and Argentina during the past several years.

Yikes!

Sources: CollectSpace, NASA’s Orbital Debris Program

A controversial concept called the electromagnetic drive, or Emdrive for short has been called impossible. But one company believes the concept is viable and has worked for several years on building demonstration models. The Emdrive is a reactionless propulsion system that supposedly generates thrust by converting electrical energy via microwaves. If it works it could provide an almost endless supply of thrust for satellites and possibly other spacecraft. But no detectable energy emanates from the device, and most scientists say the Emdrive violates the well-established principle of the conservation of momentum. Satellite Propulsion Research, Ltd. (SPR), the company working on the drive now says researchers from China have confirmed the theory behind the Emdrive, and they should have a trial engine ready to test by the end of this year.

A reactionless drive was first proposed in the 1950’s, but came to attention in 2006 when New Scientist published an article about Dr. Roger Shawyer, who founded SPR, and claimed he had constructed a prototype that produced 88 millinewtons of forces while using only 700 watts of power. The idea was met with criticism from nearly all fronts.

The idea of the Emdrive involves forces created by reflecting microwaves between opposite walls of a cavity. If a cavity could be designed which would cause the forces on one side to be greater than the other, thrust could be achieved. The proposed cavity is cone shaped, which supposedly would provide the unequal force design.

In principle, no microwaves or anything else leaves the device, and so it is considered reactionless. But Shawyers website claims that the device is not reactionless, or a perpetual motion machine, because the force is created by a “reaction between the end plates of the waveguide and the Electromagnetic wave propagated within it.”

Originally, Shawyer, a British scientist, got funding from the UK, and then from am US company. Now the researchers at China’s Northwestern Polytechnical University (NPU) in Xi’an say they have confirmed the Emdrive theory, and have gotten funding to build the device.

Their device is based on Shawyer’s theories, and if it works, it would confirm what Shawyer has been claiming all along. The Chinese lead researcher, Professor Yang Juan, previously has worked with microwave plasma thrusters, which has similar engineering principles. A recent article in Wired said he Chinese should be capable of determining whether the thruster really works or whether the apparent forces are caused by experimental errors.

If the Emdrive works, what would it mean for spaceflight? Shawyer says a solar-powered Emdrive could take a manned mission to Mars in 41 days.

Paper by Shawyer on the Emdrive (not peer reviewed)
Opposing paper by Dr. John Costella

Sources: Wired, Emdrive.com, Wiki

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While imaging the Large Magellanic Cloud, astrophotographer Doug Robertson got a real surprise when he went to process his data…. He’d accidentally recorded the uncontrolled return of the intermediate stage of a recent Russian rocket launch that just put three GLOSNASS satellites into orbit.

Eyewitnesses in Adelaide, Australia were astounded when a huge fireball lit up the skies shortly after midnight local time. The initial response was believed to be attributed to meteoric activity, but the 45 second event broke into several pieces and traveled along a parallel trajectory. Hearing the news, Robertson checked his photographic data and sure enough, during the time stamp of 12:12:38am, he’d caught the event. Like all good astronomers, the initial reaction is to immediately report and wait for an answer.

According to the Publicity Officer of the Astronomical Society of South Australia, Tony Beresford: “Last night at around 00:18CST sept 27 or 14:48 UT Sept. 26, an intermediate stage of a recent Russian launch that put 3 GLOSNASS satellites into orbit, re-entered the atmosphere and became visible travelling N-S over Adelaide. I had a full report from a person who saw the pass from Hallett Cove immediately after the event. It was an expected uncontrolled re-entry. The rocket stage had broken into several pieces. This aspect seems similar to other re-entries reported to me over the years. It took nearly a minute to pass over. A Sunday Mail reporter who rang this morning said they had a least a dozen reports. Some of the reports incorrectly used the term “meteor shower” to describe what they saw. Some meteors could give the same phenomena of multiple bodies on parallel paths, but that is not a meteor shower!!”

Is returning “space junk” a problem? You bet. In a very comprehensive article done by Nancy a few months ago called Space Debris Illustrated: The Problem in Pictures, she clearly illustrated how spent booster stages and discards from spacecraft could turn into a serious problem for future spaceflight if left unmonitored and uncontrolled. While the Russian return was expected, it’s still just another indicator of a mounting problem – inactive space hardware in orbit around the Earth .

According to NASA Shuttle program director John Shannon, “Next month’s shuttle flight to the Hubble Space Telescope faces an increased risk of getting hit by space junk because it will be in a higher, more littered orbit than usual. New number-crunching puts the odds of a catastrophic strike by orbital debris including bits of space junk at about 1-in-185 during Atlantis’ upcoming mission to Hubble. That compares to 1-in-300 odds for a shuttle flight to the International Space Station.”

Thankfully for everyone concerned there was no impact on the Shenzhou-7 mission – just a little late night excitement. Said Robertson, “Unfortunately I didn’t witness this naked eye. But as you see that main fragment/track looks extremely bright. Although rough, the crop clearly shows the number of fragments/debris surrounding the brighter tracks – reminded me off the shuttle disaster a few years ago. Glad it wasn’t anything to do with the manned Chinese mission. Wish I had put down my coffee and stepped outside a bit earlier to see it!”

Many thanks to AORAIA member, Doug Roberston for this fine catch!