A Great Week to See the Milky Way

The moon is at new phase on Sept. 18 and during this upcoming week will appear as a gradually diminishing crescent of light in the after midnight-hours, and won't be much of a hindrance to stargazing. This combined with the fact that at this particular time of the year the hazy skies of summer are giving way to clearer skies and cooler overnight temperatures means that this is an optimum week to check out the beautiful summer Milky Way.

As soon as darkness falls, it becomes evident as a wide glowing arch of variety and beauty, stretching across the sky from the northeast to southwest.

Sweep with binoculars from the Scorpion's tail, through the Summer Triangle, and then down to Cassiopeia and Perseus. You'll find concentrations of stars, clusters, large apparent gaps (such as the "Great Rift" in Cygnus), and more stars than you probably thought existed.

City dwellers miss out

Unfortunately, because of the tremendous increase in light pollution over the past 35-years, the majority of our current generation has never really seen the night sky in all its grandeur. Indeed, the Milky Way has been one of the chief victims of atmospheric pollution – by light and other factors. In most major metropolitan areas, there is very little hope of ever seeing this broad path of light at all.

However, a few years ago, I stumbled across an old observing logbook of mine where I noted that on the night of Aug. 30, 1976, I was able to glimpse the bright stretch of Milky Way that runs through Cygnus from of all places, the Throggs Neck section of The Bronx! It was one of those very special evenings, so rare in the summertime, with unusually low humidity and crisp, very transparent skies.

Sadly, I should point out, that even if the same weather pattern were to recur tonight, I wouldn't be able to repeat my 1976 observation, because the junior high school across the street from where I used to live has since installed brilliant security lighting on its roof. In addition, nearby high-pressure sodium vapor streetlights add their own garish illumination to such a degree that the general surroundings are bathed in a sort of artificial twilight; it's now so bright that you can readily read the fine print in a newspaper in the middle of the night, if you were so inclined.

Bright enough to cast shadows

Our eyes have some detail-discerning properties that not even the best long-exposure photograph can match. This advantage is considerable in the case of the Milky Way, which has such great extent that it does not require a telescope. I can recall with great fondness one particular night nearly 35-years ago, spent under the dark skies of upstate New York's Adirondack Mountains where I spent a considerable amount of time savoring the Milky Way in all of its magnificence.

So clear was the sky, that rather than appearing as a filmy band of light, the Milky Way appeared granulated in texture, and glowed so bright that it actually cast faint shadows!

I must now confess here, however, that even though I had my trusty 7 x 35 wide-angle binoculars, I hardly used them at all that night, except to pick out deep-sky objects (star clusters or nebulae) of interest. Looking at Via Lactea (the Milky Way's Latin name) through binoculars – except to view certain highlights – is a kin to closely scrutinizing a painting with a magnifying glass, which only reveals the coarse canvas, and not the actual art itself.

The Bortle Scale

A long-time friend of mine and a well-known authority on comets, John Bortle, assiduously observes the night sky from Dutchess County, New York. Back in 2001 he developed a nine-point scale which allows a person to judge just how dark (or bright) their local sky is.

For the kind of sky that now exists around my old stomping grounds in The Bronx, Mr. Bortle would likely call it a "Class 9." Specifically defined: The entire sky is brightly lit. Many stars making up familiar constellation figures are invisible, and dim constellations such as Cancer and Pisces are not seen at all. The only celestial objects that really provide pleasing telescopic views are the Moon, the planets, and a few of the brightest star clusters (if you can find them).
People who live up to 50 miles from a large metropolitan area probably have a "Class 5" sky on the Bortle scale. That's a sky where the Milky Way is very weak or invisible near the horizon and looks rather washed out overhead. Light sources are evident in most if not all directions. Over most or all of the sky, clouds are quite noticeably brighter than the sky itself.

People who live in a rural location, out to 75 miles or more from a major city likely have access to a "Class 3" sky: Some indication of light pollution is still evident along the horizon, but now the Milky Way appears quite noticeable and more complex. Your telescope is vaguely apparent at a distance of 20 or 30 feet.

But for the ultimate in skywatching, there is the "Class 1" sky . . . the kind that I enjoyed in the Adirondacks all too many of those years ago: From such a sky the Milky Way is capable of casting obvious diffuse shadows on the ground. The presence of Jupiter or Venus in the sky actually hinders your attempt to adapt to the darkness. Airglow (a very faint, naturally occurring glow most evident near to the horizon) is readily apparent. If you are observing on a grass-covered field bordered by trees, your telescope, companions, and vehicle are almost totally invisible.
Or as Mr. Bortle so eloquently put it: "This is an observer's Nirvana!"

Space Shuttle Discovery Lands Safely in California

HOUSTON - Space shuttle Discovery returned safely to Earth Friday evening, landing in California after being diverted due to rain showers over Florida.

Shuttle commander Rick Sturckow brought Discovery to a touchdownat Edwards Air Force Base in the Mojave Desert at 8:53 p.m. EDT (0153 GMT Sept. 12), after spending two days being waved off from the Kennedy Space Center in Florida due to rain showers and strong winds in the vicinity of the shuttle landing facility on both Thursday and Friday.

"Houston, Discovery, wheels stop," Sturckow said after landing.

"Welcome home Discovery!" Mission Control replied. "Congratulations on an extremely successful mission stepping up science to a new level on the International Space Station."

The landing concluded a 14-day mission to the International Space Station (ISS) that delivered new science equipment and the COLBERT treadmill - named after TV comedian Stephen. The resupply mission came to an end the day after another cargo flight launched from Japan.

Back on Earth

Returning home with Sturckow were Discovery's STS-128 mission pilot Kevin Ford and mission specialists Patrick Forrester, Danny Olivas, Jose Hernandez and European Space Agency (ESA) astronaut ChristerFuglesang. Rounding out the crew for the return to Earth was flight engineer Tim Kopra, who spent 44 days as a member of the station's Expedition 20 crew for a total of 58 days in space.

"Two months is not too long in space and it was a great opportunity," Kopra said from space Wednesday. "I will miss the sunrises and sunsets, but especially my crew who I shared my two months with onboard the space station."

Kopra's replacement aboard the station, astronaut Nicole Stott, launched with Discovery's crew just seconds before midnight on Aug. 28. Stott, who will return on the next shuttle mission targeted for launch in November, is the last astronaut scheduled to be rotated onto the station's crew by means of the U.S. orbiter. For the immediate future, all ISS crew members will launch and land on Russian Soyuz spacecraft.

The day before Discovery touched down, Japan's space agency launched its first H-2 Transfer Vehicle, or HTV-1, an unmanned cargo supply ship is due to arrive at ISS Sept. 17 and be captured by the station's robotic arm. The HTV will compliment Russian Progress and European resupply vehicles, as well as future American-built commercial spacecraft, in supporting the ISS after the space shuttle is retired in the next year or so.

"It is a very important milestone," said Kopra, "not just for the International Space Station Program, but also for the Japanese portion of the program because this is a vehicle they have constructed and it is very unique on how it will dock to the space station. It is a precursor to how we may use commercial vehicles to bring supplies to the space station."

Discovery landed with over 2,000 pounds of science experiment results and refuse from inside the outpost. Equipment and supplies were also returned on the orbiter's middeck, including a 12-inch Buzz Lightyearaction figure, which spent more than a year on the ISS as part of an educational partnership between NASA and the Walt Disney Company.

Resupply and replacements

Discovery's mission was the 30th space shuttle flight the orbiting outpost since construction began in 1998. It was dedicated to delivering vital supplies and equipment needed to support the station's six-person crew.

"Our mission has gone really well," Sturckow said Wednesday. "We transferred a large amount, about 14,800 pounds of equipment and supplies."

Most of what was transferred, including science and storage racks, a freezer to store research samples and a new sleeping compartment, were lofted inside the Leonardo Multi-Purpose Logistics Module (MPLM), a pressurized "moving van" that was relocated from Discovery's payload bay to the side of the station's Harmony node and then back.

Leonardo also carried the Combined Operational Load Bearing External Resistance Treadmill, or COLBERT. The station's second astronaut exercise treadmill, it was named after comedian Stephen Colbert of Comedy Central's "The Colbert Report" as a consolation prize for winning a NASA naming poll for its next space station module.

COLBERT launched in hundreds of parts to be assembled by the crew after the HTV-1 arrives.

Discovery's payload bay also carried the Lightweight Multi-Purpose Experiment Support Structure Carrier (LMC), a cargo pallet that supported the STS-128 mission's three spacewalks.

During the trio of outings, Olivas, Stott and Fuglesang outfitted the station with a new ammonia coolant tank, manipulating the largest object - the size of a small car - ever moved by astronauts outside the ISS. They also retrieved three exterior experiments, one European and two U.S., for return to Earth.

Olivas and Fuglesang, who performed two of the three spacewalks together, also worked to run cables to support the arrival of the Tranquility node in early 2010 but ran into problems with one of its power connectors, leaving the work to be completed during a future excursion.

With the completion of this mission's spacewalks and his previous three, Fuglesang set a record for the most time spent working in the vacuum of space by an astronaut of any nationality other than Russian or American.

The fourth of five space shuttle missions planned for this year, STS-128 marked the 37th flight of Discovery, which celebrated the 25th anniversary of its maiden launch while in space on this mission.

NASA currently plans to fly six more shuttle missions to complete construction of the station and stock the orbiting laboratory with supplies. The shuttle fleet is slated to retire in 2010 or so to make way for new spacecraft capable of leaving low Earth orbit.

The next orbiter to fly is Atlantis, which is due to launch toward the station Nov. 12 carrying even more supplies for the orbiting laboratory.

NASA Picks Moon Crater to Slam Into

When NASA's LCROSS lunar probe slams into the moon next month as planned to look for signs of water, it will aim for the south polar crater Cabeus A, the agency announced today.

The $79 million moon-impacting spacecraft is carrying an empty Centaur rocket stage, which has about the same mass as a sports utility vehicle and will be hurled into the lunar surface on Oct. 9.

Professional astronomers and backyard skywatchers will be watching the spectacle.

"The purpose of our missions is to see if there may indeed be some water ice located in some permanently shaded crater positions on the south pole of the moon," said LCROSS project manager Daniel Andrews. Other missions have provided tantalizing but so-far inconclusive evidence for water ice there.

At the announcement of the crater target, the LCROSS team dedicated the mission to the late journalist Walter Cronkite.

"It's a great honor, thank you very much. Dad would be pleased to be part of this ongoing process," his son, Chip Cronkite, said at a NASA press briefing.

What will happen

LCROSS will first release its Centaur stage rocket to impact the crater, then LCROSS itself will impact the lunar surface at about 5,580 mph (8,980 kph), and the resulting ejecta can be examined for signatures of water.

"It will kick up whatever is on the floor of the crater; that may very well include water ice," Andrews said.

More than a decade ago, the Lunar Prospector mission detected hydrogen deposits around the moon's south polar region, suggesting that some form of water ice may exist where the sun never shines.

Finding water on the moon would be a boon for future manned missions because it would eliminate the need to haul it up from Earth. The ice could be melted for drinking water, and hydrogen could be extracted for fuel.

Cabeus A was one of several finalist craters — including Shackleton, Shoemaker and Hayworth craters — examined by the team for many months. The crater sits at 81 degrees south on the moon and is relatively large (about 40 kilometers across).

The crater also meets other criteria to achieve a successful impact that throws up ejecta in a way that telescopes will be able to see it: "We want to hit a nice flat, fluffy place," said LCROSS principal investigator Anthony Colaprete.

Cabeus A seems to fit the bill, with plenty of flat areas for the spacecraft to smash into.

Data from LCROSS's sister craft, the Lunar Reconnaissance Orbiter, and the Lunar Prospector show a spot along the rim of the crater that seems to have a relatively high concentration of hydrogen, and so potentially, water.

"That is where we think the sweet spot exists," Colaprete said.

Who'll be watching

The impact will be observed by LRO, the newly refurbished Hubble Telescope, a few other space-based telescopes, and several ground-based observatories.

"This is very observable from earth," Colaprete said. "So we'll have lots of eyes on it."

NASA will even be soliciting amateur observations, said Jennifer Heldmann, lead for the LCROSS observation campaign.

LCROSS was launched in June along with LRO, which will map the lunar surface in unprecedented detail.

The team reported that the spacecraft is in good health, despite a malfunction that caused the craft to burn through half of its propellant a few weeks ago, and everything looks good for impact.

U.S. Laser Telecomm Demo Could Support Operations

WASHINGTON -- A new laser communications demonstration satellite that the U.S. Air Force may pursue would pick up one of the primary missions that was abandoned when the service’s Transformational Satellite (T-Sat) program was terminated earlier this year.

An advanced programs group at the Air Force Space and Missile Systems Center has requested information from industry by Oct. 2 for a geostationary communications satellite that would use lasers to transmit data at high speeds to aerial platforms. If the Air Force moves forward with the program, it will be directly enabled by the $2.5 billion the service invested in developing T-Sat, government and industry officials say.

“U.S industry is capable of doing this, and enough government agencies are around that can provide assistance if needed,” said Steve Townes, communications systems and research manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “I think it’s infinitely doable. You need to have some of the testing and demonstrations first to really convince people that it works.”

The T-Sat system was envisioned as the U.S. military’s all-in-one next-generation communications platform. It would have featured radio-frequency communications payloads similar to those on today’s military communications satellites, as well as several new technologies. Laser links were a cornerstone of T-Sat: each of the five geostationary satellites would have been connected via laser beams to share information around the globe without the need for terrestrial relays. The satellites also would have used laser links to relay loads of data to and from aerial platforms such as F-22 fighter jets and Global Hawk unmanned aerial vehicles.

The Lasercom Technical Demonstration (LTD) would use a medium-sized geostationary satellite platform to host a laser payload by itself or along with other government or commercial payloads, according to an Aug. 18 posting on the Federal Business Opportunities Web site. The laser payload would simultaneously support four aerial platforms with data rates of several gigabits per second. The Air Force may seek to begin an acquisition in 2011 with the goal of having the satellite on orbit in 2015 for a one-year demonstration period, the posting said. An operational capability of four additional years is desired.

While the United States has never publicly acknowledged demonstrating laser-optical communications in space — industry officials say the technology has been developed in classified programs — other nations have. In 2006, a European Space Agency satellite called Artemis demonstrated laser links from geostationary orbit to an airplane in flight with a data rate of 50 megabits per second. Japan has demonstrated high-speed laser communications between two low Earth orbiting satellites.

The laser technology that LTD would use has been certified to be low-risk and ready for operational use, said Stuart Linsky, vice president for satellite communications at Northrop Grumman Aerospace Systems of Los Angeles. Northrop Grumman was developing the communications payloads on the Lockheed Martin team that was competing against Boeing to build T-Sat. Northrop Grumman’s laser terminals demonstrated data rates of tens of gigabits per second over simulated distances of twice the distance from the ground to geostationary orbit.

“It’s a common misconception that lasercom technology is still experimental,” Linksky said. “What we were able to achieve on T-Sat was a completely integrated lasercom terminal operating at multiple tens of gigabits that was certified by [the Massachusetts Institute of Technology’s] Lincoln Laboratories and the Government Accountability Office to be at [Technological Readiness Level] 6,” meaning it has been demonstrated in a relevant environment.

The need for laser communications in space is being driven by the development of next-generation sensors for unmanned aerial vehicles, said Steve Harford, chief technologist for component technologies at Ball Aerospace and Technologies Corp. of Boulder, Colo. New sensors that will fly in coming years on the Air Force’s fleet of Global Hawk, Predator and Reaper unmanned aerial vehicles will be capable of collecting vast amounts of data that would quickly eat up all of the bandwidth on satellites that use radio frequency, Harford said. The near-infrared wavelengths used for laser-optical communications would enable data rates around 1,000 times faster than most radio frequency bands, he said. Laser communications beams are also much more narrowly focused than radio frequency transmissions and would allow spectrum to be reused by aerial platforms operating just hundreds of meters away from each other, Harford said.

Ball Aerospace was on the Boeing T-Sat team and would have provided the gimbaled laser terminals for the satellites. Ball’s hardware was demonstrated under the same conditions and received the same certifications as the Northrop Grumman hardware.

Ares 1 Booster Test Successful, But Program’s Future is Cloudy

Fresh on the heels of a report questioning the viability of NASA’s human spaceflight plans, AlliantTechsystems (ATK) test fired a solid-rocket booster that would serve as the main stage of an astronaut-launching Ares 1 rocket whose future is now in doubt.

ATK said Sept. 10 that the five-segment booster under development since 2005 performed as designed, producing 3.6 million pounds of thrust and burning for over two minutes. The test took place at the company’s solid-rocket manufacturing facility in Promontory, Utah.

Mike Kahn, ATK Space Systems executive vice president, said data obtained from the test would aid the first stage design of Ares 1, which he called “the safest launch vehicle ever developed.”

An independent panel chartered by the White House in May to review NASA’s human spaceflight program released a summary report Sept. 8 that said the Orion Crew Exploration Vehicle and its Ares 1 launcher are running about two years behind their currently planned 2015 debut. NASA and its contractors still could field Orion and Ares 1 sometime in 2017, the report says, but only if the White House agrees to boost NASA’s annual budget by some $3 billion by 2014 and de-orbits the international space station in 2016. Under this scenario, Orion and Ares would have no place to go until Moon missions commenced in the mid-2020s.

Only one other option in the report entails finishing Ares 1, a so-called budget-constrained scenario that keeps NASA funded at around $18.6 billion a year, de-orbits the space station in 2016, finishes Ares 1 and Orion about a year later, and throttles back on the development of Ares 5, a heavy-lift rocket critical to NASA’s plans for putting astronauts on the Moon. Under this scenario, the report says, Ares 5 “is not available until the late 2020s, and worse, there are insufficient funds to develop the lunar lander and lunar surface systems until well into the 2030s, if ever.”

The other three broad scenarios laid out in the report call for giving NASA more money and keeping the space station in service through 2020. These would entail canceling Ares 1 and relying on commercial rockets and spacecraft for delivering astronauts and supplies to the space station.

Shuttle Astronauts in Homestretch of Space Mission

Space shuttle Discovery astronauts entered the homestretch of their busy flight to the International Space Station Sunday and are packing up for their trip home later this week.

The shuttle's seven-astronaut crew planned to finish loading a portable cargo module with tons of trash and unneeded station equipment for the trip back to Earth. The astronauts launched into orbit Aug. 28 and wrapped up the last of three spacewalks to upgrade the space stationlate Saturday.

"We're coming into the homestretch," space station flight director Heather Rarick told reporters early Sunday.

There are 13 astronauts - a record-tying number - aboard the linked shuttle and station. In addition to Discovery's seven astronauts, there are six spaceflyers on the station: two Americans, two Russians and one astronaut each from Canada and Belgium.

One tricky task on the astronauts' to-do list Sunday is a robotic arm maneuver to prepare the station for the arrival of Japan's first unmanned cargo ship later this month. The station's Canadian-built Canadarm2 robotic arm has a grapple device at each end that allows it to move end-over-end like an inchworm to reach different parts of the station.

Japan's new cargo ship is designed to be grabbed by the station's arm when it arrives at the outpost, but one of the robotic appendage's grapple devices is a bit sticky, Rarick said. Astronauts planned to perform a so-called "triple walk-off" to move the arm several times so that its non-sticky grapple end is outstretched to await the Japanese space freighter, she added.

Discovery's crew delivered just over 18,500 pounds (8,391 kg) of cargo to the space station, including fresh supplies, new science equipment and a space treadmill named after television comedian Stephen Colbert. The astronauts will be returning more than 5,000 pounds (2,267 kg) of unneeded items to Earth when they leave the station, NASA officials have said.

The shuttle also ferried NASA astronaut Nicole Stott to the station to begin a three-month space mission. She replaced fellow spaceflyer Tim Kopra as a member of the station's crew. Kopra has lived aboard the station for nearly two months and will return home aboard Discovery.

Kopra told reporters Sunday that he's going to miss the space station, but is ready to come home. Discovery is due to undock from the space station on Tuesday and land in Florida Thursday evening.

Easy to Spot: Space Station and Shuttle Together

With the Space Shuttle Discovery scheduled to undock from the International Space Station (ISS) on Tuesday, skywatchers across much of the United States and southern Canada are in for a real treat on Tuesday and Wednesday evenings.

Weather permitting, there will be a few opportunities to see both the Discovery orbiter and the ISS flying across the sky from many locations.

The sight should easily be visible to anyone, even from brightly lit cities.

Other satellites too

The appearance of either the space shuttle or the space station moving across the sky is not in itself unusual. On any clear evening within a couple of hours of local sunset and with no optical aid, you can usually spot several orbiting Earth satellites creeping across the sky like moving stars. Satellites become visible only when they are in sunlight and the observer is in deep twilight or darkness. This usually means shortly after dusk or before dawn.

What makes the prospective upcoming passages so interesting is that you'll be able to see the two largest orbiting space vehicles in the sky at the same time.

Shuttle Discovery is expected to undock from the ISS at 3:27 p.m. Eastern Daylight Time on Tuesday. Discovery will fly around the ISS before finally pulling away from the Station at 5:10 p.m. EDT, although it should still remain at a relatively close distance to it until its scheduled return to the Kennedy Space Center in Florida Thursday.

What to expect

Both vehicles will be traveling across North America on southwest-to-northeast trajectories.
Appearing as a pair of very "bright 'stars," the ISS should appear as the somewhat brighter object and will be trailing Discovery as they move across the sky. A large telescope would be needed to make out details of the sprawling station. Traveling in their respective orbits at approximately 18,000 mph (29,000 kph), both should be visible anywhere from about one to five minutes (depending on the particular viewing pass) as they glide with a steady speed across the sky.

Because of its size and configuration of highly reflective solar panels, the space station is now, by far, the brightest man-made object currently in orbit around the Earth.

On favorable passes, it approaches magnitude -5 in brightness, which would rival the planet Venus and is more than 25 brighter than Sirius, the brightest star in the night sky. Some have even caught a glimpse of the ISS just prior to sunset or shortly after sunrise. And as a bonus, sunlight glinting directly off the solar panels can sometimes make the ISS appear to briefly flare in brilliance.

Region of visibility

Generally speaking, the tandem will be visible across southern Canada and most of the 48 contiguous United States (Hawaii and Alaska, unfortunately will not have favorable viewing passes during this upcoming week).

Across southern Canada as well as the Pacific Northwest, Northern Plains and Northeast states, there will be three, and in a few cases, as many as four evening viewing opportunities.

Over California, the central Rockies, the Midwest and the Carolinas, there will be two opportunities, while over the Desert Southwest and Deep South, the viewing options are reduced to just one.