Posted on by Ken Kremer

Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

Virtual Vesta. Taking their best guess, the science team on NASA’s Dawn Asteroid Orbiter have created a series of still images and videos (see below) to simulate what the protoplanet Vesta might look like. The exercise was carried out by mission planners at NASA's Jet Propulsion Laboratory and science team members at the German Aerospace Center and the Planetary Science Institute. Image credit: NASA/JPL-Caltech/ESA/UCLA/DLR/PSI/STScI/UMd

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The excitement is building as NASA’s innovative Dawn spacecraft closes in on its first protoplanetary target, the giant asteroid Vesta, with its camera eyes now wide open. The probe is on target to become the first spacecraft from Earth to orbit a body in the main asteroid belt and is set to arrive about four months from now in late July 2011.

Vesta is the second most massive object in the Asteroid Belt between Mars and Jupiter (map below). Since it is also one of the oldest bodies in our Solar System, scientists are eager to study it and search for clues about the formation and early history of the solar system. Dawn will spend about a year orbiting Vesta. Then it will fire its revolutionay ion thrusters and depart for Ceres, the largest asteroid in our solar system.

Dawn is equipped with three science instruments to photograph and investigate the surface mineralogy and elemental composition of the asteroid. The instruments were provided by the US, Germany and Italy. The spacecraft has just awoken from a six month hibernation phase. All three science instruments have been powered up and reactivated.

Dawn will image about 80 percent of Vesta’s surface at muliple angles with the onboard framing cameras to generate topographical maps. During the year in orbit, the probe will adjust its orbit and map the protoplanet at three different and decreasing altitudes between 650 and 200 kilometers, and thus increasing resolution. The cameras were provided and funded by Germany.

To prepare for the imaging campaign, mission planners from the US and Germany conducted a practice exercise to simulate the mission as though they were mapping Vesta. The effort was coordinated among the science and engineering teams at NASA’s Jet Propulsion Laboratory, the Institute of Planetary Research of the German Aerospace Center (DLR) in Berlin and the Planetary Science Institute in Tuscon, Ariz.

Simulated Vesta from the South Pole
This image shows the scientists' best guess to date of what the surface of the protoplanet Vesta might look like from the south pole, as projected onto a sphere 250 kilometers (160 miles) in radius. It was created as part of an exercise for NASA's Dawn mission involving mission planners at NASA's Jet Propulsion Laboratory and science team members at the Planetary Science Institute in Tuscon, Ariz. Credit: NASA/JPL-Caltech/UCLA/PSI

“We won’t know what Vesta really looks like until Dawn gets there,” said Carol Raymond in a NASA statement. Raymond is Dawn’s deputy principal investigator, based at JPL, who helped orchestrate the activity. “But we needed a way to make sure our imaging plans would give us the best results possible. The products have proven that Dawn’s mapping techniques will reveal a detailed view of this world that we’ve never seen up close before.”

Two teams worked independently and used different techniques to derive the topographical maps from the available data sets. The final results showed only minor differences in spatial resolution and height accuracy.

Using the best available observations from the Hubble Space Telescope and ground based telescopes and computer modeling techniques, they created maps of still images and a rotating animation (below) showing their best guess as to what Vesta’s surface actually looks like. The maps include dimples, bulges and craters based on the accumulated data to simulate topography and thus give a sense of Virtual Vesta in three dimensions (3 D).

“Working through this exercise, the mission planners and the scientists learned that we could improve the overall accuracy of the topographic reconstruction, using a somewhat different observation geometry,” said Nick Mastrodemo, Dawn’s optical navigation lead at JPL. “Since then, Dawn science planners have worked to tweak the plans to implement the lessons of the exercise.”

Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer
Of course no one will know how close these educated guesses come to matching reality until Dawn arrives at Vesta.

The framing camera system consists of two identical cameras developed and built by the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany and the German Aerospace Center (DLR) in Berlin.

“The camera system is working flawlessly. The dry run was a complete success,” said Andreas Nathues, lead investigator for the framing camera at the Max Planck Institute in Katlenburg-Lindau, Germany.

Since the probe came out of hibernation, the mechanical and electrical components were checked out in mid March and found to be in excellent health and the software was updated.

Dawn is a mission of many firsts.

Dawn spacecraft under construction in Cleanroom.
Picture shows close up view of two science instruments;
The twin Framing Cameras at top (white rectangles) and VIR Spectrometer at right. Credit: Ken Kremer
The spacecraft is NASA’s first mission specifically to the Asteroid Belt. It will become the first mission to orbit two solar system bodies.

The revolutionary Dawn mission is powered by exotic ion propulsion which is vastly more efficient than chemical propulsion thrusters. Indeed the ability to orbit two bodies in one mission is only enabled via the use of the ion engines fueled by xenon gas.

Vesta and Ceres are very different worlds that orbit between Mars and Jupiter. Vesta is rocky and may have undergone volcanism whereas Ceres is icy and may even harbor a subsurface ocean conducive to life.

Dawn will be able to comparatively investigate both celestial bodies with the same set of science instruments and try to unlock the mysteries of the beginnings of our solar system and why they are so different.

Dawn is part of NASA’s Discovery program and was launched in September 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida.

Virtual Vesta in 2 D.
This image shows a model of the protoplanet Vesta, using scientists' best guess to date of what the surface of the protoplanet might look like. The images incorporate the best data on dimples and bulges of Vesta from ground-based telescopes and NASA's Hubble Space Telescope. The cratering and small-scale surface variations are computer-generated, based on the patterns seen on the Earth's moon, an inner solar system object with a surface appearance that may be similar to Vesta. Credit: NASA/JPL-Caltech/UCLA/PSI
Virtual Vesta in 3 D.
This anaglyph -- best viewed through red-blue glasses -- shows a 3-D model of the protoplanet Vesta, using scientists' best guess to date of what the surface of the protoplanet might look like. Image credit: NASA/JPL-Caltech/UCLA/PSI
Dawn Spacecraft current location approaching Asteroid Vesta on March 21, 2011
Posted on by Anne Minard

Probing the Moho Boundary – Earth’s Own Unexplored Frontier

Chikyu. Credit: JAMSTEC-CDEX

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JOIDES Resolution. Credit: IODP

The boundary where Earth’s crust gives way to the unexplored mantle was first detected in 1909, because of a change in the travel of seismic waves. Named the Moho boundary for Andrija Mohorovicic, who listened to those seismic waves, the crust-mantle boundary is a frontier that remains elusive and compelling — harboring tantalizing clues as to the story of Earth’s formation — even as our technologies push into the outer reaches of the solar system and beyond.

The first serious attempts to probe the Moho boundary ran aground in the late 1950s. Now, technology already in use on a Japanese ship, combined with a United States digging program already under way, could finally yield success. Damon Teagle and Benoît Ildefonse have written about the ongoing efforts for an article in the journal Nature, released today.

Teagle is at the University of Southampton’s National Oceanography Centre in the UK, and Ildefonse is at Université Montpellier in France. They are co-chief scientists on an expedition called the IODP Expedition 335, “to obtain for the first time a section of the lower oceanic crust — the material lying just above the mantle,” they write.

The IODP is using the U.S. ship JOIDES Resolution, pictured above, which will drill from April to June this year off the coast of Costa Rica.

“This site is in ocean crust that formed superfast — at more than 20 centimetres a year, much faster than any present day crust formation,” the co-authors write. “That makes the upper crust there much thinner than elsewhere, so it is possible to reach the lower portions without having to drill very deep. Three previous expeditions to Hole 1256D have drilled down to more than 1.5 kilometres below the sea floor, into the transition zone between dikes and gabbros.”

This spring they hope to push it another 400 meters, and recover gabbros from the lower crust, “which will be the deepest types of rock ever extracted from beneath the sea floor,” even though the deepest hole reached 2,111 meters under the eastern Pacific off of Colombia, they write.

Microphotograph of a mantle xenolith, sampled on Rapa Island in French Polynesia. The colourful minerals (seen here under the microscope in cross-polarized light, each grain is about 1 to 5mm large) are olivine, the main constituent of the upper mantle. Credit : Andréa Tommasi (CNRS, Géosciences Montpellier)

Teagle and Ildefonse note that some pieces of the mantle have been thrust up to Earth’s surface during tectonic mountain building, and ejected from volcanoes and sea floor dikes. Those samples have provided clues to the mantle’s composition, but they don’t reveal the variability of the mantle — and all of the samples have been altered by the processes that revealed them.

They say the IODP mission should help to settle many debates, including how crust is formed at mid-ocean ridges, how magma from the mantle is intruded into the lower crust, the geometry and vigor of how sea water can pull heat from the lower oceanic crust and the contribution of the lower crust to marine magnetic anomalies. The project will also provide “further impetus for, and confidence in, deep ocean crust drilling,” write Teagle and Ildefonse — but it will reach a depth far less than what will be needed to actually get at the Moho boundary. It occurs at least 30 kilometers (18 miles) under the continents but just 6 kilometers (3.7 miles) under the seas.

That’s where Chikyu comes in. Launched in 2002, “Chikyu is a giant ship, capable of carrying 10 kilometres of drilling pipes, and is equipped for riser drilling in 2.5 kilometres of water,” the authors write. Although Chikyu wouldn’t yet be able to go the full distance, its design is advanced enough to be the launching pad for such efforts:

“The vessel has a riser system: an outer pipe surrounds the drill string — the steel pipe through which cores are recovered,” the co-authors write. “The drilling mud and cuttings are returned up to the vessel in the space between the two pipes. This helps to recycle the drilling mud, control its physical properties and the pressure within the drill hole and helps to stabilize the borehole walls.”

Teagle and Ildefonse say the ideal drilling program to reach the mantle boundary will happen in one of three places — off the coasts of Hawaii, Baja California and Costa Rica — where the water is the most shallow, over the coldest possible crust. Wherever and however it happens, they write, it will be worth doing:

“Drilling to the mantle is the most challenging endeavour in the history of Earth science. It will provide a legacy of fundamental scientific knowledge, and inspiration and training for the next generation of geoscientists, engineers and technologists.”

Source: Nature. See also the websites for Chikyu and JOIDES.

Posted on by Nancy Atkinson

Decadal Survey for Human Spaceflight?

Cover of Augustine Commision Report. We're still seeking a human spaceflight program

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Over at Space Politics, Jeff Foust points out that a provision for an independent study about human spaceflight was quietly included in last year’s NASA authorization act. The parameters of such a study would be similar to the decadal surveys done by the astronomy and planetary science disciplines. Foust reports that last week such a concept for human spaceflight was debated at a small conference where NASA’s Phil McAlister from the Office of Program Analysis and Evaluation said, “I believe in this Academies-like study that will allow the human spaceflight community to come together, like the science community has done for years and years, effectively. With that kind of document and blueprint… then finally, maybe, we can get the long-term consensus required to actually finish one of these programs. That is my sincere hope.”

Would such a study be helpful in giving U.S. human spaceflight unwavering direction and goals that don’t change with each presidential administration?

The debate is continuing in the comment section on Foust’s article and on Twitter, and so far the lines are divided between this being a good idea or one that would never work for human spaceflight.

Some comments suggest this type of survey would be just another exercise on paper that will accomplish nothing – and would be a repeat of the Stafford Report or the Augustine Commission, where programs and direction is suggested, but since it isn’t “law” politicians would ignore it in favor of projects in their own districts.

Others said there isn’t a strong figure in human spaceflight, such as a Steve Squyres who led the recent planetary decadal survey (although someone suggested Wayne Hale or Bill Gerstenmaier).

On the other side of the debate, still others said that some kind of consensus review is needed in order to direct NASA’s priorities with human space flight, as there has been no clear sustainable direction since the decision to build the ISS. Someone suggested this would be helpful for the international partner, as well, to know what NASA might do next.

What are your views – would a decadal survey for US human spaceflight be a good idea?

Posted on by Nancy Atkinson

Iran Claims They’ve Built a Flying Saucer

The Zohal (lower right). Credit: Fars News Agency

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Iran’s Fars News Agency revealed that the country has built an unmanned flying saucer, named “Zohal” (Saturn in Persian) which will be used for various missions including aerial imaging. UPDATE: thanks to reader Robert McCelland, we now have an actual picture of the Zohal instead of the hoaky flying saucer image that was included in the Fars article (see below). It is not really all that big — more like a remote controlled toy helicopter — but reportedly the Zohal is equipped with an auto-pilot system, GPS and two separate imaging systems with full HD 10 mega-pixel picture quality and is able to take and send images simultaneously. It was unveiled in a ceremony attended by Supreme Leader of the Islamic Revolution Ayatollah Seyed Ali Khamenei at an exhibition of strategic technologies.

No detailed specifications were supplied such as exact size and flight capabilities, (except that it can fly vertically) but the report said it could fly both indoors and outside.

The craft was designed and developed jointly by Farnas Aerospace Company and Iranian Aviation and Space Industries Association (IASIA).

The original image on the Fars site:

This image accompanied a news article in Iran about the country's own flying saucer.
Posted on by Nancy Atkinson

Kepler Spacecraft Back in Action After Computer Glitch

Artst concept of the Kepler telescope in orbit. Credit: NASA

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NASA’s Kepler spacecraft is back in planet-hunting action after a computer malfunction put it into “safe mode” for 144 hours (six days.) The anomaly occurred on March 14, 2011 immediately after the spacecraft issued a network interface card (NIC) reset command to start a computer program update. During the reset, the NIC sent invalid reaction wheel data to the flight software, which caused the spacecraft to enter the self-protecting safe mode. The NIC is the interfaces between the spacecraft’s flight software, attitude determination, and its control subsystems and sensors. Mission managers said an anomaly response team will continue to evaluate the spacecraft data to determine the cause of the safe mode event.

A safe mode is a measure the spacecraft takes to protect itself when something unexpected occurs. Kepler mission managers described what happens during a safe mode event:

“During safe mode, the spacecraft points the solar panels directly at the sun and begins to slowly rotate along a sun-aligned axis. This safe mode orientation provides the vehicle with the maximum power and limits the buildup of momentum from solar wind. The spacecraft also swapped to its backup subsystem interface box (SIB), an electronics component that provides thermal and power distribution control to all spacecraft subsystems, and powered off the photometer, the instrument used to measure light intensity to detect planets. This is a normal procedure when the spacecraft enters safe mode.”

Kepler spacecraft returned to science data collection at 2:45 p.m. EDT Sunday, March 20, 2011.

Kepler launched in 2009 to look for alien worlds, hoping to find one like Earth in the just-right “Goldilocks Zone” around another star. So far, Kepler has discovered 1,235 possible planets, with 54 of those candidates in that potential habitable zone where liquid water could exist on a planet’s surface. Further study is needed to see if any of these planets have the potential to harbor life.

But given how many potential habitable planets were found in just one area of the sky, astronomers have estimated that our Milky Way galaxy could hold as many as 50 billion alien planets, with 2 billion of those being about the size of Earth.

Stay tuned!

Source: Kepler

Posted on by Nancy Atkinson

What Did Gagarin See on His Historic Flight?

50 years ago, April 12th, Yuri Gagarin became the world’s first human to go into space. What did he see? He described it fairly well, but there are limited pictures and no video from his time in orbit. Now, through a unique collaboration between a filmmaker and ESA astronaut Paolo Nespoli on board the International Space Station, high definition video of what Gagarin might have seen has been woven together with historic recordings of the flight (subtitled in English) to create a new, free film that will be released on the 50th anniversary titled First Orbit. Above is the trailer for the film. What a perfect way to celebrate this historic moment.

“Circling the Earth in my orbital spaceship I marveled at the beauty of our planet. People of the world, let us safeguard and enhance this beauty — not destroy it!” — Yuri Gagarin.

Continue reading “What Did Gagarin See on His Historic Flight?”

Posted on by Anne Minard

Coolest Brown Dwarf Spotted by Earth-bound Telescopes

Artist's impression of the binary brown dwarf system CFBDSIR 1458+10. Credit: ESO/L. Calçada

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Astronomers have found the coldest known star — a brown dwarf in a double system about as hot as a cup of tea. The discovery blurs the line between small cold stars and large hot planets. The star, CFBDSIR 1458+10B, is the dimmer member of the binary system, about 75 light-years from Earth.

Lead study author Michael Liu, from the University of Hawaii’s Institute for Astronomy, said finding ever-cooler stars “has been one of the big themes of this field since it’s existed in the last 15 years.” Brown dwarfs are essentially failed stars; they lack enough mass for gravity to trigger the nuclear reactions that make stars shine. Liu said while the idea of a brown dwarf is many decades old, they were first confirmed in 1995, the same year the first gas giants were detected around other stars.

“Residing at the extremes of low mass, luminosity and temperature, brown dwarfs serve as laboratories for understanding gas-giant extrasolar planets as well as the faint end of the star formation process,” write the authors in the new paper, in the Astrophysical Journal. “The coolest known brown dwarfs, the T dwarfs, have temperatures (~600–1400 K) … that are more akin to Jupiter than any star.”

Liu said cool brown dwarfs are exciting to find partly because they make great proxies for studying the mysteries of water cloud formation in the atmospheres of gas giants. Such clouds are believed to form when temperatures dip below 400 to 450 K.

“We probably will never get as detailed spectra from gas giants around other stars,” he said, “because the planets are gravitationally bound to their stars. It’s very  hard to isolate the light from gas giant.” But brown dwarfs more often occur in isolation.

Three different telescopes were used to study the system: the ESO’s Very Large Telescope (VLT) in Chile, the Keck II Telescope in Hawaii and the Canada–France–Hawaii Telescope, also in Hawaii. The VLT was used to show that the composite object was very cool by brown dwarf standards.

“We were very excited to see that this object had such a low temperature, but we couldn’t have guessed that it would turn out to be a double system and have an even more interesting, even colder component,” said Philippe Delorme of the Institut de planétologie et d’astrophysique de Grenoble, a co-author of the paper.

CFBDSIR 1458+10 is the name of the binary system. The two components are known as CFBDSIR 1458+10A and CFBDSIR 1458+10B, with the latter the fainter and cooler of the two. They seem to be orbiting each other at a separation of about three times the distance between the Earth and the Sun in a period of about 30 years.

The dimmer of the two dwarfs has now been found to have a temperature of about 100 degrees Celsius, or about 370 K — the boiling point of water, and not much different from the temperature inside a sauna. By comparison the temperature of the surface of the Sun is about 5500 degrees Celsius.

The hunt for cool objects is a very active astronomical hot topic. The Spitzer Space Telescope has recently identified two other very faint objects as other possible contenders for the coolest known brown dwarfs, although their temperatures have not been measured so precisely. Future observations will better determine how these objects compare to CFBDSIR 1458+10B. Liu and his colleagues are planning to observe CFBDSIR 1458+10B again to better determine its properties and to begin mapping the binary’s orbit, which, after about a decade of monitoring, should allow astronomers to determine the binary’s mass.

Source: ESO press release and a brief interview with lead author Michael Liu. See also the paper by Liu et al., “CFBDSIR J1458+1013B: A Very Cold (>T10) Brown Dwarf in a Binary System.“

Posted on by Nancy Atkinson

Equipment to Study Hayabusa’s Asteroid Samples Damaged in Japan Earthquake

Magnified view of a dust particle in the Hayabusa canister. Credit: JAXA

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The large particle accelerator being used in to analyze the asteroid samples returned by the Hayabusa spacecraft was damaged by the March 11 earthquake in Japan, but the high energy accelerator at the KEK particle-physics laboratory will be repaired, according to this report on a Japanese website. An announcement on the KEK website said that all accelerators and experimental devices were stopped immediately “after the first shake” of the historic earthquake. “We have confirmed the radiation safety, and no hazard to the environment has been reported,” the announcement said. “Also there are no reports of casualties on both Tsukuba and Tokai campuses.” Tsukuba is in the mid-latitudes of Japan, about 50 km from Tokyo.

Apparently, the tiny asteroid particles are safe, but an official at KEK was quoted as saying (via Google Translate) “The accelerator needs to be adjusted very precisely. To suffer this much, but it takes time to recover, want to lose to the earthquake recovery.”

But the repairs to the accelerator may take a back seat to the current situation in Japan. The city of Tsukuba is going to take in refugees from Fukushima prefecture, where the heavily damaged nuclear reactor is located and the KEK facilities will provide support for radiation screening for the refugees upon their arrival.

This photo shows some of the damage to the Tsukuba Space Center in Tsukuba, Japan, the main space center for the country's JAXA agency, from the 8.9-magnitude earthquake that struck on March 11, 2011. Credit: collectSPACE.com

Tsukuba is also home to the space center that oversees Japan’s Kibo laboratory on the International Space Station, as well the JAXA’s unmanned cargo ships that deliver supplies on orbit. The space center was slightly damaged, and for awhile NASA’s Mission Control in Houston took over operations remotely. According to Robert Pearlman on collectSPACE, several of the Japanese flight control team members and flight directors from the Tsukuba Space Center happened to be in Houston when the quake struck, preparing for the Expedition 27 crew rotation, as astronaut Satoshi Furukawa will be heading the ISS in May. However, operations from the mission control rooms were resumed at 4:00 p.m. on March 22, 2011.

JAXA Flight Control Team (JFCT) resuming the Kibo operations at the Mission Control Room (MCR). Credit: JAXA

Another center, the Kakuda Space Center, located in the Miyagi region close to the most serious effects of the earthquake and tsunami, was heavily damaged, and is closed with no timetable for reopening. The Kakuda center is JAXA’s rocket development and testing center and is Japan’s equivalent of the Stennis Space Center in Mississippi.

JAXA’s Tsukuba Space Center located in Tsukuba Science City,

Additionally, the ground-breaking ceremony for a new type of particle smasher known as a “super B factory” in Tsukuba has been postponed. Japan had invested $100 million to transform the KEKB collider in Tsukuba, into a Super KEKB, which will smash electrons into positrons at 40 times the rate of the current accelerator.
Just before the quake, the Japanese Space Agency JAXA had announced they are planning a second Hayabusa mission with an explosive twist. The second mission to an asteroid probe will include an impactor that detonates an explosive on the asteroid’s surface, similar to the Deep Impact mission.

The launch was tentatively planned for launch in 2014, heading to a space rock catalogued as 162173 1999 JU3. The probe would land on the surface and, collect samples before and after the impactor blasts its way to the asteroid’s interior.

Despite the problems Hayabusa encountered along its arduous journey to and from asteroid Itokawa –including thruster, communications, gyro and fuel-leak problems, as well as uncertainty whether the probe landed on the asteroid – JAXA and the Japanese people were buoyed by the success of Hayabusa.

It is not clear how the tragic earthquake and tsunami will affect future space missions for Japan, but obviously the country has more important issues ahead of them. May the spirit of the Japanese people be lifted again.

Sources: NHK,, KEK , collectSPACE, Moon and Back, JAXA

Hat tip to Emily Lakdawalla via Twitter.

Posted on by Nancy Atkinson

Experimental Scramjet Aircraft Set for Test Flight

Artists concept of the X-51A Waverider. Credit: US Air Force

The X-51A Waverider hypersonic scramjet project is set for its second test flight today, and the U.S. Air Force hopes it will demonstrate technology that can eventually be used for more efficient transport of payloads into orbit. The craft will be carried to 15,240 meters (50,000 ft.) by a B-52 from Edwards Air Force Base in California, and be dropped over the Pacific Ocean. A booster rocket will fire, getting the Waverider to Mach 4.5; then the scramjet will kick in, and designers hope it will reach Mach 6 or more.

The X-51 Waverider program is a cooperative effort of the Air Force, DARPA, NASA, Boeing and Pratt & Whitney Rocketdyne.

In May 2010, the first test of the vehicle had sort of a “successful” flight of 200 seconds of autonomous flight, which set a duration record for an aircraft powered by a scramjet (short for “supersonic combustion ramjet”) engine. However, it was hoped that the X-51A would fly for as long as 300 seconds (or 5 minutes) and reach Mach 6. But during that flight, the Waverider suddenly lost acceleration, and the vehicle was “terminated” (destroyed – as planned, the Air Force said) while moving at Mach 5. The loss of acceleration was attributed to a design flaw, which led to hot exhaust gas leaking from the engine into electronics bays.

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The scramjet is an air-breathing engine, where intake air blows through its combustion chamber at supersonic speeds. This has been compared to lighting a match in a hurricane, and the concept has had limited success. The engine has no moving parts, and the oxygen needed by the engine to combust is taken from the atmosphere passing through the vehicle, instead of from a tank onboard, making the craft smaller, lighter and faster. Designers say it could reach speeds of anywhere from Mach 12 to Mach 24. Mach 24 is more than 29,000 km/hour (18,000 miles per hour.) This could cut an 18-hour trip to Tokyo from New York City to less than 2 hours.

Sources: NASA, The Register, Spaceports