Robot Gas Attendants Could Keep Old Satellites Chugging (SPACE.com)

NEW YORK — Aging or broken satellites orbiting Earth could one day get a second life from two different companies hoping to build new spacecraft designed to serve as robotic gas attendants and space mechanics.

The Canadian company MacDonald, Dettwiler and Associates Ltd. (MDA) is designing a spacecraft that will essentially function as a flying gas station for out-of-fuel satellites. Separately, Vivisat, which is a joint venture of rocket manufacturer Alliant Techsystems (ATK) and aerospace firm U.S. Space, has proposed a vehicle capable of performing in-orbit satellite servicing.

Both spacecraft have the potential to rescue or extend the lives of satellites in orbit, which could be a game-changing technology for the industry, officials said.

Traditionally, satellites have been constrained by how much fuel they can carry onboard. Once satellites reach the end of their lives and their tanks are empty, the dead and decommissioned spacecraft clutter low-Earth orbit. Some also pose the risk of colliding with other satellites, or of falling uncontrolled to Earth, like the NASA climate satellite UARS that plunged into the Pacific Ocean in late September.

"The space infrastructure is an incredibly fragile thing," Steve Oldham, president of Space Infrastructure Services at MDA, told attendees Wednesday (Oct. 11) at the 2011 Satellite and Content Delivery Conference & Expo. "We totally rely on that network, but strangely we don't service it, unlike any other network that we use. Road networks, sewer networks — all of those networks we service." [Photos: Space Debris Photos & Cleanup Concepts]

More than a space gas station

MDA's refueling craft, called the Space Infrastructure Servicing (SIS) vehicle, is also designed to be more than simply a gas station. In addition to loading satellites up with more fuel, the SIS vehicle will be equipped with a robotic arm and tool kit. This will allow the spacecraft to inspect, reposition, tow and make minor repairs to existing satellites.

Earlier this year, MDA announced that it had entered into an agreement with its first client. The Luxembourg and Washington-based communications satellite company Intelsat has agreed to pay $280 million over time for the SIS vehicle to refuel certain satellites in its fleet. [Video: How the Refueling Satellite Will Work]

"I think the issue of why we want to do [this] is pretty obvious," said Richard DalBello, vice president of legal and government affairs at Intelsat. "We want to be able to touch our assets, and we want to be able to see them. A large number of satellites are de-orbited that are perfectly good, perfectly functioning satellites. The ability to refuel is a very powerful technology."

But MDA is not the only company looking to service satellites in orbit.

Vivisat's so-called Mission Extension Vehicle (MEV) is also being designed to dock to satellites, but instead of transferring fuel, the MEV's own thrusters will provide propulsion and attitude control, said Bryan McGuirk, chief operating officer of Vivisat.

"We found that the majority of missions are actually retired with all subsystems functioning," McGuirk said. "We found a ready market for what we're working with here."

The value of on-orbit servicing

Vivisat's design is founded on simplicity, which should help them keep the costs low, McGuirk told SPACE.com.

"We want something that mitigates risk," he explained. "For us, the MEV accomplishes that because there's no electrical connection and no fuel exchange."

Since the MEV can dock to satellites and use its own propulsion system, the vehicle will also be able to rescue fully fueled satellites that may be in the wrong orbit and boost them into their correct position. Or, the MEV could move a satellite to a different destination to be used for a new purpose, McGuirk said.

Being able to refuel and service satellites in orbit will also help reduce the amount of orbital debris and the number of defunct satellites in space, officials said.

"We think there's a tremendous market for space awareness," DalBello said. "We believe that there is a tremendous need for greater precision in how satellites are flown in the debris environment."

For satellites that are obsolete and not worth saving with extra fuel, MDA and Vivisat's vehicles could boost them into what is known as a "graveyard orbit." This higher orbit gets them out of the way of operational spacecraft, which lowers the risk of collision. Alternatively, the refueling vehicles could tow the dead satellites into a lower position so that they can fall and break up as they re-enter Earth's atmosphere.

"This is going to happen," DalBello said. "This is not science fiction. This is within our grasp right now."

You can follow SPACE.com staff writer Denise Chow on Twitter @denisechow. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

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Spermless mosquitoes could help halt malaria spread

A puddle full of mosquitoes is seen in Jimani on the border between Dominican Republic and Haiti in this picture taken October 10, 2009.

Credit: Reuters/Eduardo Munoz

By Kate Kelland

LONDON | Mon Aug 8, 2011 3:27pm EDT

LONDON (Reuters) - Releasing genetically modified, spermless male mosquitoes into the wild could in future help to prevent malaria transmission and reduce the chances of large outbreaks of the killer disease, British scientists said on Monday.

Researchers from Imperial College London sterilized male mosquitoes by genetically modifying them to neutralize a gene required for sperm production.

In a study to see how these mosquitoes would fare when trying to get a mate, they found that female mosquitoes cannot tell if the males they mate with are fertile, or spermless and therefore unable to fertilize the females' eggs.

The researchers said findings suggest that in future it might be possible to control the size of the malaria-carrying mosquito population by introducing a genetic change that makes males sterile. Female mosquitoes would then unknowingly mate with the modified males and fail to produce any offspring.

Malaria is a mosquito-borne disease that affects up to 300 million people and kills nearly 800,000 every year. Its threat is greatest in Africa, where the World Health Organization says a child dies of malaria about every 45 seconds.

Public health experts are working toward the eventual global eradication of malaria, but progress is slow and there is a constant need for better and cheaper ways to get there.

"In the fight against malaria, many hope that the ability to genetically control the mosquito vector will one day be a key part of our armory," said Flaminia Catteruccia from Imperial's life sciences department, who led the study.

But she added that for these currently theoretical control ideas to work in practice, scientists have to establish whether the insects would continue to mate as normal, unaware that their sexual mechanisms had been tampered with.

After mating for the first and only time in her life, the female mosquito goes through certain physiological changes, then eats a meal of blood, and lays a batch of eggs.

In this research, Catteruccia's team found that this behavior pattern was the same whether or not the mating had produced fertilized eggs that could hatch into mosquito larvae.

Using Anopheles gambiae mosquitoes -- the species primarily responsible for malaria spread in Africa -- the team created spermless males by injecting ordinary mosquito eggs with a protein that disrupts the development of their testes and prevents them from producing sperm as adults.

Crucially, this did not interfere with any other sexual function or behavior in either the female or the male, they explained in their study, published in the journal Proceedings of the National Academy of Sciences.

The scientists said they were also encouraged to find that after mating with a spermless male, the female made no attempt to find another mate -- and so effectively missed out on the opportunity to reproduce and pass on her genes.

This was contrary to what they had expected based on studies of other species such as fruit flies, where females tend to mate with more than one male to ensure their eggs are fertilized.

Another group of British scientists said last year they had created genetically sterile Aedes aegypti mosquitoes which early field trials suggested could be used to halt the rapid spread of another infectious disease, dengue fever.

(Editing by David Stamp)

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'Dramatic' solar flare could disrupt Earth communications (AFP)

WASHINGTON (AFP) – An unusual solar flare observed by a NASA space observatory on Tuesday could cause some disruptions to satellite communications and power on Earth over the next day or so, officials said.

The potent blast from the Sun unleashed a firestorm of radiation on a level not witnessed since 2006, and will likely lead to moderate geomagnetic storm activity by Wednesday, according to the National Weather Service.

"This one was rather dramatic," said Bill Murtagh, program coordinator at the NWS's Space Weather Prediction Center, describing the M-2 (medium-sized) solar flare that peaked at 1:41 am Eastern time in the United States, or 0541 GMT.

"We saw the initial flare occurring and it wasn't that big but then the eruption associated with it -- we got energy particle radiation flowing in and we got a big coronal mass injection," he said.

"You can see all the materials blasting up from the Sun so it is quite fantastic to look at."

NASA's solar dynamics observatory, which launched last year and provided the high-definition pictures and video of the event, described it as "visually spectacular," but noted that since the eruption was not pointed directly at Earth, the effects were expected to remain "fairly small."

"The large cloud of particles mushroomed up and fell back down looking as if it covered an area of almost half the solar surface," said a NASA statement.

Murtagh said space weather analysts were watching closely to see whether the event would cause any collision of magnetic fields between the Sun and Earth, some 93 million miles (150 million kilometers) apart.

"Part of our job here is to monitor and determine whether it is Earth-directed because essentially that material that is blasting out is gas with magnetic field combined," he told AFP.

"In a day or so from now we are expecting some of that material to impact us here on Earth and create a geomagnetic storm," he said.

"We don't expect it to be any kind of a real severe one but it could be kind of a moderate level storm."

The Space Weather Prediction Center said the event is "expected to cause G1 (minor) to G2 (moderate) levels of geomagnetic storm activity tomorrow, June 8, beginning around 1800 GMT."

Any geomagnetic storm activity will likely be over within 12-24 hours.

"The Solar Radiation Storm includes a significant contribution of high energy protons, the first such occurrence of an event of that type since December 2006," the NWS said.

As many as 12 satellites and spacecraft are monitoring the heliosphere, and one instrument in particular on board NASA's lunar reconnaissance orbiter is measuring radiation and its effects.

"Certainly over the (two-year) lifetime of the mission this is the most significant event," said Harlan Spence, principal investigator for the cosmic ray telescope for the effects of radiation, or CRaTER.

"This is really exciting because ironically when we were developing the mission initially we thought we would be launching closer to a solar maximum when these big solar particle events typically occur," Spence told AFP.

"Instead we launched into a historic solar minimum that took a long, long time to wake up," he said.

"This is interesting and significant because it shows the Sun is returning to its more typical active state."

The resulting geomagnetic storm could cause some disruption in power grids, satellites that operate global positioning systems and other devices, and may lead to some rerouting of flights over the polar regions, Murtagh said.

"Generally it is not going to cause any big problems, it will just have to be managed," he said.

"If you fly from the United States to Asia, flying over the North Pole, there are well over a dozen flights every day," he added.

"During these big radiation storms some of these airlines will reroute the flights away from the polar regions for safety reasons to make sure they can maintain communications.

"People operating satellites would keep an eye on this, too, because geomagnetic storming can interfere with satellites in various ways whether it is the satellite itself or the signal coming down from the receiver."

The aurora borealis (Northern Lights) and aurora australis (Southern Lights) will also likely be visible in the late hours of June 8 or 9, NASA said.

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