Astronotes: August 8 - August 21, 2004

Boeing has won a $1.5 million, three-year NASA contract to develop parachute technology that enables more precise touchdowns on Mars, not only for robotic craft, but human landings too. Future Mars missions taking advantage of parachute guidance technology would be capable of landings within 2.5 miles (four kilometers) of the target area. Traditional ballistic parachutes used to decelerate planetary entry vehicles are susceptible to blustery weather on the red planet. Indeed, winds can cause spacecraft to drift away from a pre-selected landing spot. Boeing's approach is to utilize an onboard flight controller that activates a wind drift compensation parachute system during descent to reduce landing site errors. The guidance system would use three slots or flaps on the periphery of a parachute that open and close, regulating wind airflow. Like thrusters, these slots can produce lateral forces thereby providing lateral control to compensate for wind gusts, governing horizontal velocity. Building and testing of the prototype parachute system could occur in 2006 with a simulated Mars environmental drop test scheduled for the following year. The Boeing-led team includes Irvin Aerospace ofOrange County, Calif.; Global Solutions for Science and Learning in Tillamook, Oregon; and Oregon State University, Corvallis. -- Leonard David August 19

Neptune's Ragtag Moons

The 13 known moons of Neptune are a ragtag bunch similar to what exists around other giant planets, according to an analysis in the Aug. 19 issue of the journal Nature.

Five of the 13 satellites were reported in 2003 (including three in a SPACE.com article) and represented the first batch discovered since 1989. The newfound satellites range in size from 19-31 miles (30-50 kilometers). Two orbit in the same direction as Neptune's rotation, and three orbit backward, a motion known as retrograde.

All of these small satellites might be captured asteroids, according to a team led by Matthew Holman of the Harvard-Smithsonian Center for Astrophysics. One, named S/2001 N 1, might be a fragment caused by a collision with the larger Neptunian moon Nereid, Holman told SPACE.com.

Discovered in 1949, Nereid is also about 211 miles (340 kilometers) wide and may be a captured asteroid itself, scientists say. Neptune's largest satellite, Triton, is as big as Pluto, and oddly it traces a retrograde orbit -- unlike other major moons in the solar system. Astronomers say the backward motion suggests even Triton may have been captured. (Astronomers don't know if moons generally form along with a planet or separately.)

Meanwhile, two small satellites were found around Saturn recently, brining its total to 33. Jupiter has 63 known moons. More are expected for both gas giants. Uranus, the other icy giant planet, has 21. Holman said Neptune probably harbors around 50 moons, based on how many have been found, the limited nature of the search so far (Neptune is way, way out there), and what's known about the other giant planets.

-- Robert Roy Britt

MOSCOW. Aug 18 (Interfax) - The negotiations between the Russian Federal Space Agency and the first potential Russian space tourist, businessman Sergei Polonsky, concerning the organization of his flight are verging on failure.

"The parties have still been unable to reach understanding on essential terms and conditions of the contract. In particular, having agreed on the price for the flight, the parties have been unable to reach mutual understanding as regards responsibility in case the flight is cancelled for objective reasons. The final decision will be made on August 19," a source close to the negotiating process told Interfax.

According to the source's information, Polonsky has already paid several million dollars. However, he has demanded that, if the flight is cancelled for objective reasons, the money be returned.

Playing it by the numbers, the Earth's population of 6.4 billion continues to grow by more than 70 million people each year. One mid-range estimate predicts that some 8.9 billion residents will be planted in our part of the solar system a half-century from now. At present, there are two million "arrivals" on our Earth every five days.

And for those insecure social security patrons, there are more young people on Earth than ever before - all with their hands on the volume control.

Finding elbow room in the future is one thing, but the overall impact on our globe from escalating numbers of Earth dwellers is another.

A set of population-focused articles written by various experts dominates the September-October issue of World Watch magazine, published by the Worldwatch Institute, an independent research organization based in Washington, D.C.

Among the observations presented, a United Nations factoid explains that in 2000, young adults aged 15 to 29 comprised more than 40 percent of all adults in over 100 nations, all of which are developing countries. These "youth-laden"  places were roughly two-and-a-half times as likely to experience outbreaks of civil conflict in the 1990s as other nations.

The magazine also points out that population is falling -- not growing -- in countries like Germany, Italy, and Japan, leading these nations to worry about the economic and cultural implications of their aging demographics.

Overall population growth on Earth has declined from 2 percent to 1.3 percent since 1970, with a leveling off at around 9 billion people by 2050 now being predicted.

If you don't like crowds, take note. The sheer number of people on Earth is now much larger than ever before in history, the magazine explains. Some experts question whether Earth can even carry today's population at a "moderately comfortable" standard for the long term, let alone 3 billion more.

Anybody writing a business plan for Off-Earth Moving Vans, Inc.?

-- Leonard David

MOSCOW (Interfax-China) -- Moscow is ready to develop cooperation with China in space exploration, including lunar research programs, deputy head of the Federal Space Agency Nikolai Moiseyev told Interfax last week.

"Russia is ready for comprehensive consideration and discussion of the issue if China makes such a proposal," he said.

The Federal Space Agency has not received specific proposals from China about lunar research programs, he said.

The Chinese government has announced plans for a second manned space flight, and will then begin lunar research. It is planned to first launch research satellites to the Moon, to be followed by a manned landing. Chinese experts highly evaluate Russian expertise in space research.

Russia is already cooperating with China in space exploration, Moiseyev said.

A Chinese delegation visited the headquarters of the Russian Space Forces in early July. The delegation was shown the launch command center, which could control launches from the Baikonur, Plesetsk and Svobodny spaceports from Moscow.

Tour Kennedy Space Center with Space Shuttle Columbia's first pilot, Bob Crippen. Explore the U.S. Space and Rocket Center with Skylab astronaut Owen Garriott before departing on your own Space Camp parent-child experience. Own a small piece of the equipment netting used by moonwalker Charlie Duke that traveled to the lunar surface aboard Apollo 16.

These and more than a dozen astronaut artifacts and experiences are to be offered during the second annual Astronaut Scholarship Foundation (ASF) Silent Auction to benefit college students who exhibit motivation, imagination, and exceptional performance in the science or engineering field of their major.

Presented in cooperation with collectSPACE, online bidding begins Monday, August 23 and extends through  the morning of Saturday, September 4, when the bidding goes live at the Universal Autograph Collector Club's Show and astronaut dinner in Burbank, California.

Registration and a catalog preview are now available online at: http://www.collectspace.com/auction/

Other astronauts donating of their time or possessions include James Lovell, who donated a mission emblem carried on his perilous Apollo 13 flight; Apollo 7 astronaut Walter Cunningham who will accompany the winning bidder on a tour of Johnson Space Center; Al Worden, Apollo 15 Command Module Pilot, who has donated a piece of his mission photography-inspired artwork; and four-time Space Shuttle veteran Dan Brandenstein who will visit the classroom of the winning bidder's child.

Through the years, the Foundation has awarded more than $2 million in scholarships to 183 college science and engineering students. ASF currently awards $170,000 annually to 17 students. Last year's auction raised $60,000 for the Foundation.

A piece of science fiction became fact this week as Japanese researchers launched not one, but two large solar sails, successfully deploying the gossamer-thin sheets in space during a brief rocket flight.

It marked the first time any solar sail was successfully deployed in space, despite a number of sail research programs in nations around the world.

Solar sails are designed to be pushed along by light particles and have long-been a target for propulsion researchers hoping to find ways around the need for spacecraft to lug heavy propellant with them on long space voyages.

Scientists with Japan's Institute of Space and Astronautical Science (ISAS), part of the Japanese Aerospace Exploration Agency (JAXA), launched their reflective solar sail duo aboard a small S-310 rocket during an Aug. 9 flight. The launch was staged from the Uchinoura Space Center in Kagoshima, Japan at 3:15 p.m. local time.

While the space shot lasted just over six minutes, it was long enough for the to deploy a clover-shaped sail in space about 1.6 minutes into the flight and 75 miles (122 kilometers) above Earth. At 3.8 minutes after launch, the clover sail was jettisoned and a second, fan-shaped sail unfurled at an altitude of 105 miles (169 kilometers). After deploying its two sails, the rocket plunged into the Pacific Ocean.

Both metallic sails measured just 7.5 micrometers thick. One micrometer (or micron) is about the size of an average bacterium.

In addition to ISAS's successful sail deployment, NASA's solar sail propulsion team at Marshall Space Flight Center (MSFC) announced their successful Aug. 9 deployment of two 33-foot (10-meter) sails in ground-based vacuum chambers.

-- Tariq Malik

The Defense Advanced Research Projects Agency (DARPA) is delving into creation of a "Pulsar Network" for satellites to know their exact whereabouts in space and time.

The idea is to create a celestial seasoning of sorts, adding a little pizzazz to the Global Positioning System (GPS) constellation of satellites in Earth orbit.

"We're on our way...basically creating a pulsar network," said Tony Tether, Director of DARPA during opening remarks at the Small Satellites: Complimentary or Disruptive Technology conference, being held this week at Utah State University.

The effort is dubbed X-ray Source-based Navigation for Autonomous Position Determination (XNAV) Program, and is being spearheaded under DARPA's tactical technology work, Tether told the audience.

XNAV is a research and development look into an autonomous position, attitude and time determination system using celestial sources in the X-ray band of the electromagnetic spectrum. The goal of this program is to prove the feasibility and viability of the use of celestial sources, pulsars as well as neutron stars for position, attitude and time determination of low Earth orbiting spacecraft.

Such a capability would provide an autonomous backup system to military navigation and communication satellites. Using XNAV, a satellite in space will be able to find where it is using pulsars.

In the GPS world there's a term called "Dilution of precision" - a measure of the quality of the GPS data being received from the satellites. "I don't think we'll have that problem with pulsars," Tether said. "First of all, there's lots of pulsars," Tether said. "What hasn't been done is that they haven't been characterized. It would be useful for anywhere in the solar system...a great way to navigate around, all over space."

-- Leonard David

NASA has backed off a decision to decommission weather-watching satellite and will instead keep it operational through the current hurricane season.

The space agency had decided earlier this year to end the working life of the Tropical Rainfall Measuring Mission (TRMM). NASA informed the Japanese Aerospace Exploration Agency (JAXA), a partner on the satellite, that it intended decommission TRMM satellite in the weeks ahead and steer it into the ocean in 2005.

TRMM was launched in 1997 on a planned 18-month mission to study rainfall in the Earth's tropical regions. The $650 million spacecraft, designed to last at least three years, is now in its seventh year of operations.

An outcry from scientists led to the change in decision. In particular, a request to keep it running came from the National Oceanic and Atmospheric Administration (NOAA), parent of the U.S. National Weather Service, according to a NASA statement last week.

"We have decided to extend TRMM through this year's hurricane season in our effort to aid NOAA in capturing another full season of storm data," said Dr. Ghassem Asrar, deputy associate administrator of NASA's Science Mission Directorate.

TRMM complements other satellites by measuring rainfall over the global tropics, allowing scientists to study the transfer of water and energy among the global atmosphere and ocean surface that form the faster portions of the Earth's climate system. Hurricanes develop in tropical waters and draw on humid air and warm water for their strength.

-- SPACE.com Staff

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