Endeavour to Take to the Skies One Last Time

One of NASA’s 747 SCAs carries Endeavour from Edwards to Kennedy in 2008 following its landing at Edwards to conclude shuttle mission STS-126. (NASA)

Endeavour, mounted atop NASA’s modified 747 Shuttle Carrier Aircraft (SCA), will become the last Space Shuttle orbiter to soar aloft when it departs Monday, Sept. 17, from Kennedy Space Center in Florida on a three-day flight to Los Angeles International Airport.

In cooperation with the Federal Aviation Administration, the SCA is scheduled to conduct low-level flyovers at about 1,500 feet above many locations along the planned flight path, including Cape Canaveral, Stennis Space Center, New Orleans and stopovers in both Houston and Edwards Air Force Base in California.

Read more about NASA’s SCA: “The World’s Greatest Piggy Back Ride”

Flyovers of Sacramento and San Francisco are also planned before landing at LAX on the 20th.

After arrival at LAX, Endeavour will be demated from the SCA and spend a few weeks at a United Airlines hangar undergoing preparations for transport and display. The orbiter then will travel through Inglewood and Los Angeles city streets on a 12-mile journey from the airport to the California Science Center, arriving on the evening of Oct. 13.

See a map of Endeavour’s planned route across LA here.

Beginning Oct. 30, the shuttle will be on permanent display in the science center’s Samuel Oschin Space Shuttle Endeavour Display Pavilion, beginning its new mission commemorating past achievements in human spaceflight and educating and inspiring future generations of explorers.

On August 16 Endeavour was moved from KSC’s Orbiter Processing Facility 2 to the Vehicle Assembly Building, where it’s being housed temporarily until its departure on the 17th. (Photo above at right; read more here.)

On May 16, 2011, Endeavour launched on its final mission, STS-134:

Completed in July 1990, Endeavour (OV-105) was the last shuttle orbiter to be constructed for NASA. Endeavour completed 25 missions, spent 299 days in orbit, and orbited Earth 4,671 times while traveling 122,883,151 miles.

On Twitter and along Endeavour’s route? NASA encourages people to share their shuttle sightings using the hashtags #spottheshuttle and #OV105, Endeavour’s orbiter vehicle designation.

Read more and find the full flight itinerary on the NASA news release.

Is Triton Hiding an Underground Ocean?

Voyager 2 mosaic of Neptune’s largest moon, Triton (NASA)

At 1,680 miles (2,700 km) across, the frigid and wrinkled Triton is Neptune’s largest moon and the seventh largest in the Solar System. It orbits the planet backwards – that is, in the opposite direction that Neptune rotates – and is the only large moon to do so, leading astronomers to believe that Triton is actually a captured Kuiper Belt Object that fell into orbit around Neptune at some point in our solar system’s nearly 4.7-billion-year history.

Briefly visited by Voyager 2 in late August 1989, Triton was found to have a curiously mottled and rather reflective surface nearly half-covered with a bumpy “cantaloupe terrain” and a crust made up of mostly water ice, wrapped around a dense core of metallic rock. But researchers from the University of Maryland are suggesting that between the ice and rock may lie a hidden ocean of water, kept liquid despite estimated temperatures of  -97°C (-143°F), making Triton yet another moon that could have a subsurface sea.

How could such a chilly world maintain an ocean of liquid water for any length of time? For one thing, the presence of ammonia inside Triton would help to significantly lower the freezing point of water, making for a very cold — not to mention nasty-tasting — subsurface ocean that refrains from freezing solid.

In addition to this, Triton may have a source of internal heat — if not several. When Triton was first captured by Neptune’s gravity its orbit would have initially been highly elliptical, subjecting the new moon to intense tidal flexing that would have generated quite a bit of heat due to friction (not unlike what happens on Jupiter’s volcanic moon Io.) Although over time Triton’s orbit has become very nearly circular around Neptune due to the energy loss caused by such tidal forces, the heat could have been enough to melt a considerable amount of water ice trapped beneath Triton’s crust.

Related: Titan’s Tides Suggest a Subsurface Sea

Another possible source of heat is the decay of radioactive isotopes, an ongoing process which can heat a planet internally for billions of years. Although not alone enough to defrost an entire ocean, combine this radiogenic heating with tidal heating and Triton could very well have enough warmth to harbor a thin, ammonia-rich ocean beneath an insulating “blanket” of frozen crust for a very long time — although eventually it too will cool and freeze solid like the rest of the moon. Whether this has already happened or still has yet to happen remains to be seen, as several unknowns are still part of the equation.

“I think it is extremely likely that a subsurface ammonia-rich ocean exists in Triton,” said Saswata Hier-Majumder at the University of Maryland’s Department of Geology, whose team’s paper was recently published in the August edition of the journal Icarus. “[Yet] there are a number of uncertainties in our knowledge of Triton’s interior and past which makes it difficult to predict with absolute certainty.”

Still, any promise of liquid water existing elsewhere in large amounts should make us take notice, as it’s within such environments that scientists believe lie our best chances of locating any extraterrestrial life. Even in the farthest reaches of the Solar System, from the planets to their moons, into the Kuiper Belt and even beyond, if there’s heat, liquid water and the right elements — all of which seem to be popping up in the most surprising of places — the stage can be set for life to take hold.

Read more about this here on Astrobiology.net.

Inset image: Voyager 2 portrait of Neptune and Triton taken on August 28, 1989. (NASA)

NASA’s Colossal Crawler Gets Souped-Up for SLS

Shuttle Discovery riding one of KSC’s crawler-transporters to Launch Pad 39B in June 2005 (NASA)

One of NASA’s two iconic crawler-transporters — the 2,750-ton monster vehicles that have delivered rockets from Saturns to Shuttles to launch pads at Kennedy Space Center for nearly half a century — is getting an upgrade in preparation for NASA’s new future in space flight.

131 feet long, 113 feet wide and with a breakneck top speed of 2 mph (they’re strong, not fast!) NASA’s colossal crawler-transporters are the only machines capable of hauling fully-fueled rockets the size of office buildings safely between the Vehicle Assembly Building and the launch pads at Kennedy Space Center. Each 3.5-mile one-way trip takes around 6 hours.

Now that the shuttles are retired and each in or destined for its permanent occupation as a relic of human spaceflight, the crawler-transporters have not been doing much crawling or transporting down the 130-foot-wide, Tennessee river-rock-coated lanes at KSC… but that’s soon to change.

According to an article posted Sept. 5 on TransportationNation.org, crawler 2 (CT-2) is getting a 6-million-pound upgrade, bringing its carrying capacity from 12 million pounds to 18 million. This will allow the vehicle to bear the weight of a new generation of heavy-lift rockets, including NASA’s Space Launch System (SLS).

Read: SLS: NASA’s Next Big Thing

In addition to carrying capacity CT-2 will also be getting new brakes, exhausts, hydraulics and computer systems.

Part of a $2 billion plan to upgrade Kennedy Space Center for a future with both NASA and commercial spaceflight partners, the crawler will have two of its onboard power engines replaced — but the original generators that power its eight enormous tread belts will remain, having been thoroughly inspected and deemed to be “in pristine condition” according to the article by Matthew Peddie.

When constructed in the early 1960s, the crawler-transporters were the largest tracked vehicles ever made and cost $14 million — that’s about $100 million today. But were they to be built from scratch now they’d likely cost even more, as the US “is no longer the industrial powerhouse it was in the 1960s.”

Still, it’s good to know that these hardworking behemoths will keep bringing rockets to the pad, even after the shuttles have been permanently parked.

“When they built the crawler, they overbuilt it, and that’s a great thing because it’s able to last all these years. I think it’s a great machine that could last another 50 years if it needed to,” said Bob Myers, systems engineer for the crawler.

You can see some really great full panoramas of the CT-2 at the NASATech website, where photographer John O’Connor took three different panoramic views while the transporter was inside the Vehicle Assembly Building at KSC in Highbay 1. There’s even a pan close-up of the giant cleats that move the transporter.

Read the full article on TransportationNation.org here, and find out more about the crawler-transporters here and here.

Since the Apollo years the transporters have traveled an accumulated 2,526 miles, about the same distance as a one-way highway trip from KSC to Los Angeles.

Inset image: the Apollo 11 Saturn V, tower and mobile launch platform atop the crawler-transporter during rollout on May 20, 1969. (NASA) Bottom image: NASA Administrator Charles Bolden on the site of the CT-2 upgrade in August 2012. Each of the crawler’s 456 tread shoes weighs about one ton. (NASA)

Researchers Send Mars Some Radar Love

A radar map of Mars’ major volcanic regions created by the Arecibo Observatory in Puerto Rico (John Harmon et al., NAIC)

Even though we currently have several missions exploring Mars both from orbit and on the ground, there’s no reason that robots should be having all the fun; recently a team of radio astronomers aimed the enormous 305-meter dish at Puerto Rico’s Arecibo Observatory at Mars, creating radar maps of the Red Planet’s volcanic regions and capturing a surprising level of detail for Earth-based observations.

The team, led by John Harmon of the National Astronomy and Ionosphere Center, bounced radar waves off Mars from Arecibo’s incredibly-sensitive dish, targeting the volcanic Tharsis, Elysium, and Amazonis regions. Depolarized radar imagery best reveals surface textures; the rougher and less uniform a surface is, the brighter it appears to radar while smooth, flat surfaces appear dark.

What the radar maps portray are very bright — and therefore rough — areas on most of the major volcanoes, although some regions do appear dark, such as the summit of Pavonis Mons.

This likely indicates a covering by smoother, softer material, such as dust or soil. This is actually in line with previous observations of the summit of Pavonis Mons made with the HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter, which showed the summit to appear curiously soft-edged and “out-of-focus”, creating a blurry optical illusion of sorts.

It’s thought that the effect is the result of the build-up of dust over millennia, carried across the planet by dust storms but remaining in place once settled because the Martian wind is just so extremely thin — especially at higher altitudes.

The team also found bright areas located away from the volcanoes, indicating rough flows elsewhere, while some smaller volcanoes appeared entirely dark — again, indicating a possible coating of smooth material like dust or solidified lava flows.

The resolution of the radar maps corresponds to the wavelength of the signals emitted from Arecibo; the 12.6 centimeter signal allows for surface resolution of Mars of about 3 km.

The team’s paper was published in the journal Icarus on July 25. Read more on the Red Planet Report here.

The iconic 305-meter radar telescope at Arecibo Observatory in Puerto Rico

 

Curiosity’s Laser Leaves Its Mark

Before-and-after images from Curiosity’s ChemCam  micro-imager show holes left by its million-watt laser (NASA/JPL-Caltech/LANL/CNES/IRAP/LPGN/CNRS)

PEWPEWPEWPEWPEW! Curiosity’s head-mounted ChemCam did a little target practice on August 25, blasting millimeter-sized holes in a soil sample named “Beechey” in order to acquire spectrographic data from the resulting plasma glow. The neat line of holes is called a five-by-one raster, and was made from a distance of about 11.5 feet (3.5 meters).

Sorry Obi-Wan, but Curiosity’s blaster is neither clumsy nor random!

Mounted to Curiosity’s “head”, just above its Mastcam camera “eyes”, ChemCam combines a powerful laser with a telescope and spectrometer that can analyze the light emitted by zapped materials, thereby determining with unprecedented precision what Mars is really made of.

Read: Take a Look Through Curiosity’s ChemCam

For five billionths of a second the laser focuses a million watts of energy onto a specific point. Each of the 5 holes seen on Beechey are the result of 50 laser hits. 2 to 4 millimeters in diameter, the holes are much larger than the laser point itself, which is only .43 millimeters wide at that distance.

ChemCam’s laser allows Curiosity to zap and examine targets up to 23 feet (7 meters) away. Credit: J-L. Lacour/CEA/French Space Agency (CNES)

“ChemCam is designed to look for lighter elements such as carbon, nitrogen, and oxygen, all of which are crucial for life,” said Roger Wiens, principal investigator of the ChemCam team. “The system can provide immediate, unambiguous detection of water from frost or other sources on the surface as well as carbon – a basic building block of life as well as a possible byproduct of life. This makes the ChemCam a vital component of Curiosity’s mission.”

Visit the official ChemCam site for more information.

What Has the Kuiper Belt Taught Us About The Solar System?

Over 4 billion miles (6.7 billion km) from the Sun, the Kuiper Belt is a vast zone of frozen worlds we still know very little about. Image: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)

Today marks the 20th anniversary of the discovery of the first Kuiper Belt Object, 1992QB1. KBOs are distant and mostly tiny worlds made up of ice and rock that orbit the Sun at incredible distances, yet are still very much members of our Solar System. Since 1992 over 1,300 KBOs have been found, and with NASA’s New Horizons spacecraft speeding along to its July 2015 rendezvous with Pluto and Charon (which one could argue are technically the first KBOs ever found) and then onwards into the Belt, we will soon know much more about these far-flung denizens of deep space.

But how has the discovery of the Kuiper Belt — first proposed by Gerard Kuiper in 1951 (and in a fashion even earlier by Kenneth Edgeworth) — impacted our current understanding of the Solar System? New Horizons Principal Investigator Alan Stern from the Southwest Research Institute recently discussed this on his mission blog, “The PI’s Perspective.”

First, Stern lists some of the surprisingly diverse physical aspects of KBOs that have been discovered so far:

  • Some are red and some are gray;
  • The surfaces of some are covered in water ice, but others (like Pluto) have exotic volatile ices like methane and nitrogen;
  • Many have moons, though none with more known moons than Pluto;
  • Some are highly reflective (like Pluto), others have much darker surfaces;
  • Some have much lower densities than Pluto, meaning they are primarily made of ice. Pluto’s density is so high that we know its interior is about 70% rock in its interior; a few known KBOs are more dense than Pluto, and even rockier!

But although these features are fascinating in themselves, just begging for further exploration, Stern notes that there are three very important lessons that the Kuiper Belt has taught us about the Solar System:

1. Our planetary system is much larger than we had ever thought.

“In fact, we were largely unaware of the Kuiper Belt — the largest structure in our solar system — until it was discovered 20 years ago,”  Stern writes. “It’s akin to not having maps of the Earth that included the Pacific Ocean as recently as 1992!”

2. Planetary locations and orbits can change over time.

“This even creates whole flocks of migration of planets in some cases. We have firm evidence that many KBOs (including some large ones like Pluto), were born much closer to the Sun, in the region where the giant planets now orbit.”

3. Our solar system, and likely others as well, was very good at making small planets.

“Today we know of more than a dozen dwarf planets in the solar system, and those dwarfs already outnumber the number of gas giants and terrestrial planets combined. But it is estimated that the ultimate number of dwarf planets we will discover in the Kuiper Belt and beyond may well exceed 10,000. Who knew?”

And with a little jab at the whole Pluto-isn’t-a-planet topic, Stern asks: “And which class of planet is the misfit now?”

Read: Was Pluto Ever REALLY a Planet?

The discovery of the Kuiper Belt has shown us that our solar system — and very likely planetary systems across the galaxy, even the Universe — aren’t neat and tidy things that can be easily summed up with grade-school models or chalkboard diagrams. Instead they are incredibly diverse and dynamic, continually evolving and consisting of countless, varied worlds spanning enormous distances… yet still connected through the ever-present effects of gravity (not to mention the occasional-yet-unavoidable collision.)

“What an amazing set of paradigm shifts in our knowledge the Kuiper Belt has brought so far. Our quaint 1990s and earlier view of the solar system missed its largest structure!”

– Alan Stern, New Horizons Principal Investigator

Read more about the New Horizons mission here.

 The first KBO identified, 1992 QB1 (European Southern Observatory)

Effects of Einstein’s Elusive Gravitational Waves Observed

Chandra data (above, graph) on J0806 show that its X-rays vary with a period of 321.5 seconds, or slightly more than five minutes. This implies that the X-ray source is a binary star system where two white dwarf stars are orbiting each other (above, illustration) only 50,000 miles apart, making it one of the smallest known binary orbits in the Galaxy. According to Einstein's General Theory of Relativity, such a system should produce gravitational waves - ripples in space-time - that carry energy away from the system and cause the stars to move closer together. X-ray and optical observations indicate that the orbital period of this system is decreasing by 1.2 milliseconds every year, which means that the stars are moving closer at a rate of 2 feet per year.
Potential stellar collision. Credit: Chandra

Two white dwarfs similar to those in the system SDSS J065133.338+284423.37 spiral together in this illustration from NASA. Credit: D. Berry/NASA GSFC

Locked in a spiraling orbital embrace, the super-dense remains of two dead stars are giving astronomers the evidence needed to confirm one of Einstein’s predictions about the Universe.

A binary system located about 3,000 light-years away, SDSS J065133.338+284423.37 (J0651 for short) contains two white dwarfs orbiting each other rapidly — once every 12.75 minutes. The system was discovered in April 2011, and since then astronomers have had their eyes — and four separate telescopes in locations around the world — on it to see if gravitational effects first predicted by Einstein could be seen.

According to Einstein, space-time is a structure in itself, in which all cosmic objects — planets, stars, galaxies — reside. Every object with mass puts a “dent” in this structure in all dimensions; the more massive an object, the “deeper” the dent. Light energy travels in a straight line, but when it encounters these dents it can dip in and veer off-course, an effect we see from Earth as gravitational lensing.

Einstein also predicted that exceptionally massive, rapidly rotating objects — such as a white dwarf binary pair — would create outwardly-expanding ripples in space-time that would ultimately “steal” kinetic energy from the objects themselves. These gravitational waves would be very subtle, yet in theory, observable.

Read: Astronomy Without a Telescope: Gravitational Waves

What researchers led by a team at The University of Texas at Austin have found is optical evidence of gravitational waves slowing down the stars in J0651. Originally observed in 2011 eclipsing each other (as seen from Earth) once every six minutes, the stars now eclipse six seconds sooner. This equates to a predicted orbital period reduction of about 0.25 milliseconds each year.*

“These compact stars are orbiting each other so closely that we have been able to observe the usually negligible influence of gravitational waves using a relatively simple camera on a 75-year-old telescope in just 13 months,” said study lead author J.J. Hermes, a graduate student at The University of Texas at Austin.

Based on these measurements, by April 2013 the stars will be eclipsing each other 20 seconds sooner than first observed. Eventually they will merge together entirely.

Although this isn’t “direct” observation of gravitational waves, it is evidence inferred by their predicted effects… akin to watching a floating lantern in a dark pond at night moving up and down and deducing that there are waves present.

“It’s exciting to confirm predictions Einstein made nearly a century ago by watching two stars bobbing in the wake caused by their sheer mass,” said Hermes.

As of early last year NASA and ESA had a proposed mission called LISA (Laser Interferometer Space Antenna) that would have put a series of 3 detectors into space 5 million km apart, connected by lasers. This arrangement of precision-positioned spacecraft could have detected any passing gravitational waves in the local space-time neighborhood, making direct observation possible. Sadly this mission was canceled due to FY2012 budget cuts for NASA, but ESA is moving ahead with developments for its own gravitational wave mission, called eLISA/NGO — the first “pathfinder” portion of which is slated to launch in 2014.

The study was submitted to Astrophysical Journal Letters on August 24. Read more on the McDonald Observatory news release here.

Inset image: simulation of binary black holes causing gravitational waves – C. Reisswig, L. Rezzolla (AEI); Scientific visualization – M. Koppitz (AEI & Zuse Institute Berlin)

*The difference in the eclipse time is noted as six seconds even though the orbital period decay of the two stars is only .25 milliseconds/year because of a pile-up effect of all the eclipses observed since April 2011. The measurements made by the research team takes into consideration the phase change in the J0651 system, which experiences a piling effect — similar to an out-of-sync watch — that increases relative to time^2 and is therefore a larger and easier number to detect and work with. Once that was measured, the actual orbital period decay could be figured out.

Curiosity Sends Back Incredible Hi-Res Views of Mt. Sharp

Wow — what a view! This image, released today, is a high-resolution shot of the Curiosity rover’s ultimate goal: the stratified flanks of Gale Crater’s 3.4-mile (5.5-km) high central peak, Mount Sharp. The image was taken with Curiosity’s 100mm telephoto Mastcam as a calibration test… if views like this are what we can expect from the MSL mission, all I can say is (and I’ve said it before) GO CURIOSITY!


“This is an area on Mount Sharp where Curiosity will go,” said Mastcam principal investigator Michael Malin of Malin Space Science Systems. “Those layers are our ultimate objective. The dark dune field is between us and those layers. In front of the dark sand you see redder sand, with a different composition suggested by its different color. The rocks in the foreground show diversity — some rounded, some angular, with different histories. This is a very rich geological site to look at and eventually to drive through.”

Read more: Take a Trip to Explore Gale Crater

The gravel-strewn region in the foreground is Curiosity’s immediate landing area. Then the ground dips into a low depression called a swale, then rises up again to the edge of a crater that’s rimmed with larger rocks. Quite a bit beyond that (about 2.2 miles/3.7 km away) are fields of dunes composed of darker material, and then the hummocky base of Mount Sharp itself begins to rise up about 3.4 miles (5.5 km) in the distance.

The topmost ridges of Mount Sharp visible above are actually 10 miles (16.2 km) away.

A crop of the full-size image shows a large rock at the foot of a knoll that’s about the same size as Curiosity (which is this big compared to a person and previous rovers):

The rocky mound just behind the boulder in that image is itself about 1,000 feet (300 meters) across and 300 feet (100 meters) high. Gale Crater isn’t a place for a faint-hearted rover!

The colors have been modified from the original image in order to help better discern landforms and differences in surface materials. Here, the images look more like what we’d see under natural Earthly lighting.

Curiosity already is returning more data from the Martian surface than have all of NASA’s earlier rovers combined.

“We have an international network of telecommunications relay orbiters bringing data back from Curiosity,” said JPL’s Chad Edwards, chief telecommunications engineer for NASA’s Mars Exploration Program. “Curiosity is boosting its data return by using a new capability for adjusting its transmission rate.”

See more images from Curiosity here, and keep up to date on the mission at the MSL website here.

“The knowledge we hope to gain from our observation and analysis of Gale Crater will tell us much about the possibility of life on Mars as well as the past and future possibilities for our own planet. Curiosity will bring benefits to Earth and inspire a new generation of scientists and explorers, as it prepares the way for a human mission in the not too distant future.”

– NASA Administrator Charles Bolden in a message transmitted to the Curiosity rover and then back to Earth, August 27, 2012

Images: NASA/JPL-Caltech

A New Species of Type Ia Supernova?

Artist’s conception of a binary star system that produces recurrent novae, and ultimately, the supernova PTF 11kx. (Credit: Romano Corradi and the Instituto de Astrofísica de Canarias)

Although they have been used as the “standard candles” of cosmic distance measurement for decades, Type Ia supernovae can result from different kinds of star systems, according to recent observations conducted by the Palomar Transient Factory team at California’s Berkeley Lab.


Judging distances across intergalactic space from here on Earth isn’t easy. Within the Milky Way — and even nearby galaxies — the light emitted by regularly pulsating stars (called Cepheid variables) can be used to determine how far away a region in space is. Outside of our own local group of galaxies, however, individual stars can’t be resolved, and so in order to figure out how far away distant galaxies are astronomers have learned to use the light from much brighter objects: Type Ia supernovae, which can flare up with a brilliance equivalent to 5 billion Suns.

Type Ia supernovae are created from a special pairing of two stars orbiting each other: one super-dense white dwarf drawing material in from a companion until a critical mass — about 40% more massive than the Sun — is reached. The overpacked white dwarf suddenly undergoes a rapid series of thermonuclear reactions, exploding in an incredibly bright outburst of material and energy… a beacon visible across the Universe.

Because the energy and luminance of Type Ia supernovae have been found to be so consistently alike, distance can be gauged by their apparent brightness as seen from Earth. The dimmer one is when observed, the farther away its galaxy is. Based on this seemingly universal similarity it’s been thought that these supernovae must be created under very similar situations… especially since none have been directly observed — until now.

An international team of astronomers working on the Palomar Transient Factory collaborative survey have observed for the first time a Type Ia supernova-creating star pair — called a progenitor system — located in the constellation Lynx. Named PTF 11kx, the system, estimated to be some 600 million light-years away, contains a white dwarf and a red giant star, a coupling that has not been seen in previous (although indirect) observations.

“It’s a total surprise to find that thermonuclear supernovae, which all seem so similar, come from different kinds of stars,” says Andy Howell, a staff scientist at the Las Cumbres Observatory Global Telescope Network (LCOGT) and a co-author on the paper, published in the August 24 issue of Science. “How could these events look so similar, if they had different origins?”

The initial observations of PTF 11kx were made possible by a robotic telescope mounted on the 48-inch Samuel Oschin Telescope at California’s Palomar Observatory as well as a high-speed data pipeline provided by the NSF, NASA and Department of Energy. The supernova was identified on January 16, 2011 and supported by subsequent spectrography data from Lick Observatory, followed up by immediate “emergency” observations with the Keck Telescope in Hawaii.

“We basically called up a fellow UC observer and interrupted their observations in order to get time critical spectra,” said Peter Nugent, a senior scientist at the Lawrence Berkeley National Laboratory and a co-author on the paper.

The Keck observations showed the PTF 11kx post-supernova system to contain slow-moving clouds of gas and dust that couldn’t have come from the recent supernova event. Instead, the clouds — which registered high in calcium in the Lick spectrographic data — must have come from a previous nova event in which the white dwarf briefly ignited and blew off an outer layer of its atmosphere. This expanding cloud was then seen to be slowing down, likely due to the stellar wind from a companion red giant.

(What’s the difference between a nova and a supernova? Read NASA’s STEREO Spots a New Nova)

Eventually the decelerating nova cloud was impacted by the rapidly-moving outburst from the supernova, evidenced by a sudden burst in the calcium signal which had gradually diminished in the two months since the January event. This calcium burst was, in effect, the supernova hitting the nova and causing it to “light up”.

The observations of PTF 11kx show that Type Ia supernova can occur in progenitor systems where the white dwarf has undergone nova eruptions, possibly repeatedly — a scenario that many astronomers had previously thought couldn’t happen. This could even mean that PTF 11kx is an entirely new species of Type Ia supernova, and while previously unseen and rare, not unique.

Which means our cosmic “standard candles” may need to get their wicks trimmed.

“We know that Type 1a supernovae vary slightly from galaxy to galaxy, and we’ve been calibrating for that, but this PTF 11kx observation is providing the first explanation of why this happens,” Nugent said. “This discovery gives us an opportunity to refine and improve the accuracy of our cosmic measurements.”

Source: Berkeley Lab news center

Inset images: PTF 11kx observation (BJ Fulton, Las Cumbres Observatory Global Telescope Network) / The 48-inch Samuel Oschin Telescope dome at Palomar Observatory. Video: Romano Corradi and the Instituto de Astrofísica de Canarias

Neil Armstrong, First Man on the Moon, Dies at 82

Former NASA astronaut Neil A. Armstrong was born in Wapakoneta, Ohio, on August 5, 1930

Today we mourn the loss of a true hero and icon of a generation, if not an entire century: Neil Alden Armstrong, former NASA astronaut and first person to set foot on the Moon, has passed away due to complications from cardiovascular surgery. Armstrong had recently turned 82 years old on August 5.

His family has issued the following statement:

We are heartbroken to share the news that Neil Armstrong has passed away following complications resulting from cardiovascular procedures.

Neil was our loving husband, father, grandfather, brother and friend.

Neil Armstrong was also a reluctant American hero who always believed he was just doing his job. He served his Nation proudly, as a navy fighter pilot, test pilot, and astronaut. He also found success back home in his native Ohio in business and academia, and became a community leader in Cincinnati.

He remained an advocate of aviation and exploration throughout his life and never lost his boyhood wonder of these pursuits.

As much as Neil cherished his privacy, he always appreciated the expressions of good will from people around the world and from all walks of life.

While we mourn the loss of a very good man, we also celebrate his remarkable life and hope that it serves as an example to young people around the world to work hard to make their dreams come true, to be willing to explore and push the limits, and to selflessly serve a cause greater than themselves.

For those who may ask what they can do to honor Neil, we have a simple request. Honor his example of service, accomplishment and modesty, and the next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink.

His death was reported at 2:45 p.m. ET.

Armstrong commanded the Apollo 11 spacecraft that landed on the moon on July 20, 1969, and he radioed back to Earth the historic news: “That’s one small step for a man, one giant leap for mankind.”

In a statement issued by the White House, U.S. President Barack Obama said “Today, Neil’s spirit of discovery lives on in all the men and women who have devoted their lives to exploring the unknown – including those who are ensuring that we reach higher and go further in space. That legacy will endure — sparked by a man who taught us the enormous power of one small step.”

Neil Armstrong, along with fellow astronauts Buzz Aldrin, Michael Collins and John Glenn, were honored with the Congressional Gold Medal on November 16, 2011.

Godspeed, Mr. Armstrong. You were — and will always be — a true inspiration to so many. You’ll be missed.

“In my own view, the important achievement of Apollo was a demonstration that humanity is not forever chained to this planet, and our visions go rather further than that, and our opportunities are unlimited.”

— Neil A. Armstrong

Top image: NASA. Inset images: Armstrong leads the crew from the Manned Spacecraft Operations Building to the transfer van on July 16, 1969 and a portrait of Armstrong taken inside the LM after the first lunar EVA. Via the Project Apollo Archive.