Jason Major, Author at Universe Today

December 20, 2012December 23, 2015 by Jason Major

NASA’s Final 2012 Doomsday Debunking Video (We Hope)

Despite countless articles published over the course of several years to the contrary, despite videos and interviews with some of the world’s most prominent and well-respected astronomers, despite new archaeological discoveries and well-established knowledge, despite the laws of physics, for crying out loud (and, curiously enough, even despite the fact that parts of the world are, at the time of this writing, already well within the supposed “doomsday” with nary a Nibiru in sight) many people are still wondering what will happen on the much-touted December 21, 2012, aka “doomsday” per the end of the 13th b’ak’tun of the Maya calendar (or something like that.) After all, if it’s trending on Twitter it must be important, right?

Well, yes and no. No because there’s not a shred of truth to the whole thing (except for the fact that there were Maya and they had a calendar) but yes because many people are actually very concerned about… well, I guess about the safety of the world. (Don’t believe me? Read this.) Which is in itself reasonable, I suppose. So in the nature of public outreach and the attempt to spread real information to combat the other kind, NASA’s has released yet one more video interview with astrophysicist David Morrison, director of the Carl Sagan Center for Study of Life in the Universe at the SETI Institute. I don’t know if David could tell you how to replace a broken head gasket or perform an appendectomy, but when it comes to space he knows his stuff. So check out the video, be not alarmed, and pass it on to anyone you know who might still be feeling the b’ak’tun blues.

See you on the 22nd! (Still skeptical? Check out some other videos and links below.)

And here’s a “reality check” from JPL’s Don Yeomans, an expert on near-Earth objects and asteroids:

So rest assured, the only astronomical event expected for the 21st is the winter solstice (summer in the south), which happens every year on every planet with an axial tilt with no ill effects (besides perhaps a sudden sinking realization that you’re nowhere near done with your holiday shopping.) Happy solstice!

December 20, 2012December 23, 2015 by Jason Major

The Most Remote Workplace on Earth

ESA’s Proba-1 satellite imaged the French-Italian Concordia base on November 21, 2012 (ESA)

Located in one of the loneliest locations on Earth, the French-Italian Concordia station was captured on high-resolution camera by ESA’s Proba-1 microsatellite last month, showing the snow-covered base and 25 square kilometers of the virtually featureless expanse of Antarctic ice surrounding it.

A cluster of scientific research buildings situated 3233 meters above sea level in the Antarctic interior, Concordia is one of the only permanently-crewed stations on the southern continent. Around 12–15 researchers and engineers spend months — sometimes over a year — in isolation at Concordia, where during the winter months there are no deliveries, no chance of evacuation, temperatures below -80 ºC (-112 ºF) and the next closest station is 600 km (370 miles) away. It’s like working on another planet.

And that’s precisely why they’re there.

The researchers who live and work at Concordia are there because of the station’s incredible remoteness and harsh conditions. This allows them to study not only the pristine Antarctic ice beneath their feet but also how humans behave in such an environment, where a small team must learn to work together and merely venturing outside can be a hazardous task.

It’s the next closest thing to an actual outpost on Mars, or the Moon. Even the astronauts on the ISS aren’t as far removed from the rest of the world.

(Although the night sky views from Concordia can be comparably stunning.)

Concordia Base boasts some of the clearest, darkest — and coldest — skies on Earth (ESA/IPEV/PNRA – A. Salam)

“Boredom and monotony are the enemy,” wrote ESA-sponsored medical researcher Dr. Alex Salam, regarding his 2009 13-month stay. “The darkness has a habit of sucking the motivation out of even the hardiest. But despite the effects the darkness can have on sleep, mood and cognitive performance, there is something inherently special about the Antarctic night. The heavens present a view that many stargazers can only ever dream of. You just have to try and catch a glimpse of the stars before your eyelashes freeze together!

“Seeing the station from a distance with the Milky Way towering far above it never failed to make me feel both awe inspired and simultaneously insignificant.”

And another recent long-term resident of Concordia, Dr. Alexander Kumar, who departed the base on November 15, shared this reflection as his year-long term was approaching its end:

“Concordia has, in removing me from civilisation where sometimes it is harder to step back, enabled me to see the bigger picture, provide a unique experience and reminded me of somethings, setting a course and direction for the future… I think once you come to Antarctica, drawn to it under a spell like a seaman to a mermaid, you never can break the link you form with this raw, rugged and ruthlessly beautiful and enticing continent.”

The Sun returns to the Antarctic plateau (ESA/IPEV/PNRA – A. Salam)

“It’s the closest thing I’ll ever have to living on another planet.”

– Dr. Alex Salam

Read more about Concordia on the newly-redesigned ESA site here.

In orbit for over 11 years, Proba-1’s unique images are used by hundreds of scientific teams worldwide. To date its main Compact High Resolution Imaging Spectrometer (CHRIS) has acquired over 20,000 environmental science images used by a total of 446 research groups in 60 countries.

December 19, 2012December 23, 2015 by Jason Major

Evidence for Active Hollows Formation on Mercury

MESSENGER targeted-observation image of the interior of Eminescu crater

A recent image acquired by NASA’s MESSENGER spacecraft shows the interior of Eminescu, a youngish 130-km (80 mile) wide crater just north of Mercury’s equator. Eminescu made science headlines last year with MESSENGER’s discovery of curious eroded blotches called “hollows” scattered across its interior and surrounding its central peak, and now it looks like the spacecraft may have spotted some of these strange features in their earliest stages of formation along the inner edge of the crater’s rim.

First announced in September 2011, hollows have now been identified in many areas across Mercury. They had showed up in previous images as only bright spots, but once MESSENGER established orbit in March 2011 and began its high-resolution imaging of Mercury’s surface it soon became clear that these features were something totally new.

The lack of craters within hollows indicates that they are relatively young. It was suggested that they may be the result of an ongoing process on Mercury — a suggestion supported by this recent image, acquired on November 19, 2012.

In addition to the hollows seen in the smooth central part of the crater and around the base of the central peak, there are also some small bright spots visible within the knobby terrain extending from the base of the crater wall (see detail at right). These bright spots could well be very young hollows, revealing a process in action that is, as far as we know, unique to the planet Mercury.

It’s thought that hollows are formed by the solar wind constantly blasting Mercury’s surface, scouring away deposits of volatile materials in its crust that have been left exposed by impacts.

The image above shows an area about 42 km across. Read more on the MESSENGER mission site here.

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

December 18, 2012December 23, 2015 by Jason Major

One of the Largest Astronomical Images Ever Made

The northern portion of the Cygnus Loop, as seen in an enormous new panorama from the National Optical Astronomy Observatory (NOAO) and WIYN partners

Looking for a stunning new desktop image to wrap up the year? Try this: it’s an amazing panorama of the Cygnus Loop, a supernova remnant located 1,500 light-years away in the constellation (you guessed it) Cygnus. The full-size image, acquired with the wide-field Mosaic camera on the WIYN 0.9-meter telescope at Kitt Peak, Arizona, is a staggering 600 million pixels in size — over 1.68 gigabytes — making it one of the largest astronomical images ever made!

See the full image (and links to download larger versions) below:

2000-pixel-wide version of the full Cygnus Loop panorama

The entire structure of the Cygnus Loop, the gaseous remains of a supernova that occurred 5,000 – 10,000 years ago, covers an area nearly 45 times the size of the full Moon in the sky.

In the image, hydrogen alpha, sulphur, and oxygen ions correspond to the red, green, and blue color values, respectively.

“Images like this are amazing because they can remind you of the big picture and beauty that surrounds us.”

– Dr. Richard Cool, MMT Observatory

From the NOAO press release:

Astronomers estimate the supernova explosion that produced the nebula occurred between 5,000 to 10,000 years ago. First noted in 1784 by William Herschel, it is so large that its many parts have been catalogued as separate objects, including NGC 6992, NGC 6995 and IC 1340 along the eastern (left) side of the image, NGC 6974 and NGC 6979 near the top-center, and the Veil Nebula (NGC 6960) and Pickering’s Triangle along the western (right) edge. The bright star near the western edge of the image, known as 52 Cygnus, is not associated with the supernova.

“Often, astronomical research reduces images to dry tables of numerical information that we analyze in order to more deeply understand our universe,” said Dr. Richard Cool, astronomer at the MMT Observatory in Arizona, who originally obtained the images in 2003 while still a graduate student. “Images like this are amazing because they can remind you of the big picture and beauty that surrounds us.”

This incredible image demonstrates that even relatively small telescopes are capable of producing cutting-edge research, when equipped with modern cameras.

Got bandwidth to spare? Download the full-size 1686.5 MB TIFF image here, or find other versions on the NOAO page here.

Image Credit: T.A. Rector (University of Alaska Anchorage), Richard Cool (University of Arizona) and WIYN/NOAO/AURA/NSF. Inset image: original dome of the Kitt Peak 0.9-meter telescope. (NOAO/AURA/NSF)

December 18, 2012December 23, 2015 by Jason Major

Behold! Hubble’s Heavenly Holiday “Ornament”

Planetary nebula NGC 5189 as seen by Hubble’s Wide Field Camera 3. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

It may be just a tad too big to hang on your tree but this bright, twisted planetary nebula would make a beautiful holiday ornament… if scaled a bit down to size, of course.

(Click the image to see it in its full festive glory!)

NGC 5189 is a planetary nebula that lies 1,800 light-years away in the southern constellation Musca. The gorgeous image above, acquired by Hubble’s Wide Field Camera 3 on October 8, 2012, shows the glowing streamers of oxygen, sulfur and hydrogen that are being blown far into space from the hot star star at its heart — HD 117622 (at right.)

The expelled gas forms a double structure, with a series of central blue lobes surrounded by a twisted helix of bright streamers, called radial filaments. These filaments are the result of fast-moving material from the star impacting previously expelled, slower-moving gas, which becomes visible due to ionizing radiation.

The twisted shapes — as opposed to the circular or spherical structures found in many planetary nebulae — may be the result of an unseen binary partner to HD 117622, which over time would affect its rotational orientation.

“The likely mechanism for the formation of this planetary nebula is the existence of a binary companion to the dying star,” said scientist Kevin Volk in a Gemini Observatory article from 2006. “Over time the orbits drift due to precession and this could result in the complex curves on the opposite sides of the star.”

The surrounding stars in the image were captured in visible and near-infrared light.

Read more on the Hubble site here, and check out a video below that zooms into the region of the sky where NGC 5189 is located:

Video credit: NASA, ESA, and G. Bacon (STScI)

December 18, 2012December 23, 2015 by Jason Major

Russia’s Soyuz Spacecraft: 46 Years and Still Soaring High

In just a couple of days a Soyuz rocket will lift off from the Baikonur Cosmodrome, carrying NASA astronaut Tom Marshburn, Canadian Space Agency astronaut Chris Hadfield, and Russian Federal Space Agency cosmonaut Roman Romanenko within the TMA-07M capsule on a two-day trip to the ISS. While many improvements have been made to the Soyuz rockets and spacecraft since the first launch in 1966, the bottom line is that the Soyuz have become the world’s most used launch vehicles due to their consistent performance and relatively low cost.

Here, CSA astronaut Chris Hadfield talks about the Soyuz, briefly describing the strengths of the Russian technology that will once again take him and fellow Expedition 34/35 crew members to the ISS, where in March of next year he will become the first Canadian to take command of the Station.

“This is a safe and reliable and proven way to leave the Earth, and each successive Soyuz is different; each one has small changes. The role of the astronaut is to learn those small changes… and learn to apply them.”

– Canadian astronaut Chris Hadfield

The T version of the Soyuz craft began flying manned missions in 1980 and in 1986 the TM versions were transporting crews to Mir. The TMA upgrade addressed previous astronaut/cosmonaut height restrictions and permits the Soyuz to be used as a lifeboat for ISS crews, if necessary.

Find out more about the long history of the Soyuz spacecraft here, and read more about today’s Soyuz rollout here.

Video: CSA. Inset image: NASA/Carla Cioffi

December 17, 2012December 23, 2015 by Jason Major

The Paranal and the Shadow of the Earth

This beautiful photo, taken by ESO photo ambassador Babak Tafreshi, shows the European Southern Observatory’s Very Large Telescope array and VISTA telescope atop the peaks of the Cerro Paranal in Chile’s Atacama Desert. In the distance the Earth’s shadow extends outward toward the horizon, divided from the bluer daytime sky by the dusky pink “Belt of Venus.”

At an altitude of 2,635 meters (8,645 feet) the Paranal looks down onto a sea of clouds covering the Pacific Ocean, visible at right, whose shores lie 12 km in the distance.

Image credit: ESO/B. Tafreshi (twanight.org)

December 8, 2012December 23, 2015 by Jason Major

X-ray Burst May Be the First Sign of a Supernova

GRB 080913, a distant supernova detected by Swift. This image merges the view through Swift’s UltraViolet and Optical Telescope, which shows bright stars, and its X-ray Telescope. Credit: NASA/Swift/Stefan Immler

The first moments of a massive star going supernova may be heralded by a blast of x-rays, detectable by space telescopes like Swift, which could then tell astronomers where to look for the full show in gamma rays and optical wavelengths. These findings come from the University of Leicester in the UK where a research team was surprised by the excess of thermal x-rays detected along with gamma ray bursts associated with supernovae.

“The most massive stars can be tens to a hundred times larger than the Sun,” said Dr. Rhaana Starling of the University of Leicester Department of Physics and Astronomy. “When one of these giants runs out of hydrogen gas it collapses catastrophically and explodes as a supernova, blowing off its outer layers which enrich the Universe.

“But this is no ordinary supernova; in the explosion narrowly confined streams of material are forced out of the poles of the star at almost the speed of light. These so-called relativistic jets give rise to brief flashes of energetic gamma-radiation called gamma-ray bursts, which are picked up by monitoring instruments in space, that in turn alert astronomers.”

Powerful gamma ray bursts — GRBs — emitted from supernovae can be detected by both ground-based observatories and NASA’s Swift telescope. Within seconds of detecting a burst (hence its name) Swift relays its location to ground stations, allowing both ground-based and space-based telescopes around the world the opportunity to observe the burst’s afterglow.

But the actual moment of the star’s collapse, when its collapsing core reacts with its surface, isn’t observed — it happens too quickly, too suddenly. If these “shock breakouts” are the source of the excess thermal x-rays (a.k.a. black body emission) that have been recently identified in Swift data, some of the galaxy’s most energetic supernovae could be pinpointed and witnessed at a much earlier moment in time — literally within the first seconds of their birth.

“This phenomenon is only seen during the first thousand seconds of an event, and it is challenging to distinguish it from X-ray emission solely from the gamma-ray burst jet,” Dr. Starling said. “That is why astronomers have not routinely observed this before, and only a small subset of the 700+ bursts we detect with Swift show it.”

More observations will be needed to determine if the thermal emissions are truly from the initial collapse of stars and not from the GRB jets themselves. Even if the x-rays are determined to be from the jets it will provide valuable insight to the structure of GRBs… “but the strong association with supernovae is tantalizing,” according to Dr. Starling.

Read more on the University of Leicester press release here, and see the team’s paper in the Nov. 28 online issue of the Monthly Notices of the Royal Astronomical Society here (Full PDF on arXiv.org here.)

Inset image: An artist’s rendering of the Swift spacecraft with a gamma-ray burst going off in the background. Credit: Spectrum Astro. Find out more about the Swift telescope’s instruments here.

December 7, 2012April 26, 2016 by Jason Major

Do We Really Need Dark Matter?

Hubble mosaic of massive galaxy cluster MACS J0717.5+3745, thought to be connected by a filament of dark matter. Credit: NASA, ESA, Harald Ebeling (University of Hawaii at Manoa) & Jean-Paul Kneib (LAM)

Even though teams of scientists around the world are at this very moment hot on the trail of dark matter — the “other stuff” that the Universe is made of and supposedly accounts for nearly 80% of the mass that we can’t directly observe (yet) — and trying to quantify exactly how so-called “dark energy” drives its ever-accelerating expansion, perhaps one answer to these ongoing mysteries is maybe they don’t exist at all.

This is precisely what one astronomer is suggesting in a recent paper, submitted Dec. 3 to Astrophysical Journal Letters.

In a paper titled “An expanding universe without dark matter and dark energy” (arXiv:1212.1110) Pierre Magain, a professor at Belgium’s Institut d’Astrophysique et de Géophysique, proposes that the expansion of the Universe could be explained without the need for enigmatic material and energy that, to date, has yet to be directly measured.

In addition, Magain’s proposal puts a higher age to the Universe than what’s currently accepted. With a model that shows a slower expansion rate during the early Universe than today, Magain’s calculations estimate its age to be closer to 15.4 – 16.5 billion years old, adding a couple billion more candles to the cosmic birthday cake.

The benefit to a slightly older Universe, Magain posits, is that it’s not so uncannily close to the apparent age of the most distant galaxies recently found — such as MACS0647-JD, which is 13.3 billion light-years away and thus (based on current estimates, see graphic at right) must have formed when the Universe was a mere 420 million years old.

Using accepted physics of how time behaves based on Einstein’s theory of general relativity — namely, how the passage of time is relative to the position and velocity of the viewer (as well as the intensity of the gravitational field the viewer is within) — Magain’s model allows for an observer located within the Universe to potentially be experiencing a different rate of time than a hypothetical viewer located outside the Universe. Not to be so metaphysical as to presume that there are external observers of our Universe but merely to say that an external point would be a fixed one against which one could benchmark a varying passage of time inside the Universe, Magain calls this universal relativity.

A viewer experiencing universal relativity would, Magain claims, always measure the curvature of the Universe to be equal to zero. This is what’s currently observed, a “flatness problem” that Magain insinuates is strangely coincidental.

By attributing an expanding Universe to dark energy and the high velocities of stars along the edges of galaxies (as well as the motions of galaxy clusters themselves) to dark matter, we may be introducing ad hoc elements to the Universe, says Magain. Instead, he proposes his “more economical” model — which uses universal relativity — explains these apparently accelerating, increasingly expanding behaviors… and gives a bigger margin of time between the Big Bang and the formation of the first galactic structures.

There’s quite a bit of math involved, and since I never claimed to understand physics equations you can check out the original paper here.

While intriguing, the bottom line is that dark energy and dark matter have still managed to elude science, existing just outside the borders of what can be observed (although the gravitational lensing effects of what’s thought to be dark matter filaments have been observed by Hubble) and Magain’s paper is merely putting another idea onto the table — one that, while he recognizes needs further testing and relies upon very specific singular parameters, doesn’t depend upon invisible, unobservable and mysteriously dark “stuff”. Whether it belongs on the table or not will be up to other astrophysicists to decide.

Prof. Magain’s research was supported by ESA and the Belgian Science Policy Office.

At right: Artist’s impression of dark matter (h/t to Steve Nerlich)

Note: this is “just” a submitted paper and has not been selected for publication yet. Any hypotheses proposed are those of the author and are not endorsed by this site. (Personally I like dark matter. It’s fascinating stuff… even if we can’t see it. Want an astrophysicist’s viewpoint on the existence of dark matter? Check out Ethan Siegel’s blog response here.)

December 6, 2012December 23, 2015 by Jason Major

Titan’s Gravity Indicates a Thicker, Uneven Icy Crust

Color composite of Titan and Dione made from Cassini images acquired in May 2011. (NASA/JPL/SSI/J. Major)

It’s long been speculated that Saturn’s moon Titan may be harboring a global subsurface ocean below an icy crust, based on measurements of its rotation and orbit by NASA’s Cassini spacecraft. Titan exhibits a density and shape that indicates a pliable liquid internal layer — an underground ocean — possibly composed of water mixed with ammonia, a combination that would help explain the consistent amount of methane found in its thick atmosphere.

Now, further analysis of Cassini gravity measurements by a Stanford University team has shown that Titan’s ice layer is thicker and less uniform than originally estimated, indicating a more complex internal structure — and a stronger external influences for its heat.

Titan’s liquid subsurface ocean was previously estimated to be in the neighborhood of 100 km (62 miles) thick, sandwiched between a rocky core below and an icy shell above. This was based on the behavior of Titan in its orbit — or, more precisely, how Titan’s shape changes along the course of its orbit, as measured by Cassini’s radar instrument.

Because Titan’s 16-day orbit is not perfectly circular the moon experiences a stronger gravitational pull from Saturn at certain points than at others. As a result it’s flattened at the poles and constantly changing shape slightly — an effect called tidal flexing. Along with the decay of radioactive materials in its core, this flexing generates the internal heat that helps keep a subsurface ocean liquid.

A team of researchers from Stanford University, led by Howard Zebker, professor of geophysics and electrical engineering, used recent Cassini measurements of Titan’s topography and gravity to determine that the icy layer between the moon’s surface and ocean is up to twice as thick as previously thought — and it’s considerably thicker at the equator than at the poles.

“The picture of Titan that we get has an icy, rocky core with a radius of a little over 2,000 kilometers, an ocean somewhere in the range of 225 to 300 kilometers thick and an ice layer that is 200 kilometers thick,” said Zebker.

Different thicknesses of Titan’s ice layer would mean that there’s less heat being generated internally by the decay of radioactive materials in Titan’s core, because that type of heat would be more or less globally uniform. Instead, tidal flexing caused by the gravitational interactions with Saturn and neighboring smaller moons must play a stronger role in heating Titan’s insides.

With Cassini’s new measurements of Titan’s gravity, Zebker and his team calculated that the icy layer below Titan’s flattened poles is 3,000 meters (about 1.8 miles) thinner than average, while at the equator it’s 3,000 meters thicker than average. Combined with the moon’s surface features, this makes the average global thickness of the ice layer to be more like 200 km, not 100.

Heat generated by tidal flexing — which is more strongly felt at the poles — is thought to be the cause of the thinner ice there. Thinner ice would mean there’s more liquid water beneath the poles, which is denser and thus would exert a stronger gravitational pull… exactly what’s been found in Cassini’s measurements.

The findings were announced Tuesday, Dec. 4 at the AGU convention in San Francisco. Read more on the Stanford University news page.