'The full moon rises over the only planet we have ever called home,' Tweeted astronaut Chris Hadfield.
We never get tired of these amazing views from the International Space Station, but this one has it all: a silvery Moon setting into the Earth’s atmosphere, the dazzling Milky Way rising into a brilliant sunrise, airglow of all colors, popping lightning, shimmering aurorae, and incredible views of the stunning space station and our gorgeous planet. Brian Tomlinson put this one together, using stills from the Johnson Space Center’s “Gateway to Astronaut Photography of the Earth.”
Below is a recent image taken by Canadian astronaut Chris Hadfield showing the Moon hovering above Earth, as seen from the ISS, similar to the views in the opening of the video:
New supernova 2013aa, discovered by Stu Parker on February 13, 2013, is southwest of the spiral galaxy NGC 5643 in the southern constellation Lupus. This photo was taken three days later. Credit: Joseph Brimacombe
I live in the frozen north by choice, but occasionally I yearn for warmer places like Tucson and Key West. These feelings usually start in late February, when after nearly four months of winter, the season feels endless. Today I wish I could head down south for another reason – to see a very bright supernova in a galaxy in Lupus.
Stu Parker. Credit: BOSS
SN 2013aa popped off in the barred spiral galaxy NGC 5643 in the constellation Lupus the Wolf 34 million years ago, but no one knew its light was wiggling its way across the cosmos to Earth until New Zealand amateur astronomer Stu Parker nailed it during one of his regular supernovae hunts. Parker recorded it on Feb. 13, 2013. Since it was so far from the galaxy, he thought at first it was a hot pixel (electronic artifact) or an asteroid. Another look at the galaxy 5 minutes later confirmed it was really there.
Good thing. It turned out upon confirmation to be the brightest supernova he and his band of supernova hunters had ever discovered.
Stu is a member of a 6-man amateur supernova search team from Australia and New Zealand called BOSS (Backyard Observatory Supernova Search). They’ve been working together since 2008 with the goal of searching for and reporting supernovae in the southern sky. When a member finds a candidate, they contact profession astronomers who follow up using large telescopes. To date the group has found 56 supernovae with Stu discovering or co-discovering 45 of them!
Map showing the sky looking south around 5 a.m. local time from Tuscon, Arizona. The new supernova in galaxy NGC 5643 is low in the southern sky before dawn for observers in the southern U.S. and points south. Created with Stellarium
From the northern U.S., much of Lupus and especially the supernova never make it above the horizon, but from about 35 degrees north and points south, SN 2013aa is fair game. The “new star” lies southwest of the core of galaxy NGC 5643, which shines at magnitude 10, bright enough to see in a 6-inch telescope from a dark sky. The supernovae is still climbing in brightness and today gleams at about 11.6 magnitude – no problem in that 6-inch if you’re equipped with a good map or photo to help get you there.
In this annotated version of the Joseph Brimacombe’s photo, I’ve suggested a straightforward “star hop” from the galaxy’s core to 2013aa using brighter foreground stars.
Based on the study of 2013aa’s light, astronomers have classified it as Type Ia. Before the explosion, the star was a white dwarf, a superdense, planet-sized object with the mass of the sun. Tiny but mighty, the white dwarf’s powerful gravity pulled material from a nearby companion star down to its surface. When a dwarf puts on enough pounds to exceed 1.4 times the sun’s mass, the extra material increases the pressure and temperature of the core and the star burns explosively.
In a Type Ia supernova, a white dwarf (left) draws matter from a companion star until its mass hits a limit which leads to runaway burning and a catastrophic explosion that obliterates the star.
The energy released increases the star’s brightness to 5 billion times that of the sun. Matter from the blast streaks into space at speeds of 3,000-12,000 miles per second. Yes, this is a BIG deal and one of the most energetic events the universe has to offer. No wonder amateurs like myself can’t get enough of them.
NGC 5643 is best placed in the southern sky around 5 a.m. local time. From Lexington, KY. (latitude 38 degrees N.) it’s only 8 degrees high or slightly less than one fist held at arm’s length. Tuscon’s better at 14 degrees and Key West (latitude 25 N) best at 21. Farther south, your views will continue to improve. And the pleasant temperatures can’t hurt either.
You can start with the bright pair of Saturn and Spica midway up in the southern sky. Look about two outstretched fists below them to find Theta Centauri and from there “three fingers” to the lower left (southeast) to Eta Centauri. The galaxy is about 1 1/2 degrees southwest of Eta. The supernova will look like an 11 1/2 magnitude star 74″ west and 180″ south of the galaxy’s bright core. Use the annotated photo to help guide you straight to it.
To keep track of the 2013aa’s progress as well as view many more photos, I highly recommend David Bishop’s Latest Supernovae site.
This collage of 72 individual radar-generated images of asteroid 2012 DA14 was created using data from NASA's 230-foot (70-meter) Deep Space Network antenna at Goldstone, Calif. Image credit: NASA/JPL-Caltech
The Jet Propulsion Laboratory has released an initial view of radar observations of asteroid 2012 DA14 generated from data obtained by NASA’s Goldstone Solar System Radar, taken on Feb. 15-16, 2013 as the asteroid headed away from Earth. While these first radar data aren’t very picturesque, they do reveal one obvious thing: this asteroid is tumbler.
The movie is comprised of 73 radar “images” looped nine times. JPL said that during the observations, the space rock’s distance increased from 120,000 to 314,000 km (74,000 to 195,000 miles) from Earth. The resolution here is 4 meters per pixel.
The images span close to eight hours and clearly show an elongated object undergoing roughly one full rotation. JPL said the images suggest that the asteroid has a long axis of about 40 meters (130 feet). The radar observations were led by scientists Lance Benner and Marina Brozovic of JPL. Additional Goldstone radar observations were taken as the asteroid continued to move away from Earth, on February 18, 19, with more observations scheduled on the 20th.
Radar is one of the best techniques for studying an asteroid’s size, shape, rotation state, surface features and surface roughness, and for improving calculations of its orbit. Radar measurements of asteroid distances and velocities often enable computation of asteroid orbits much further into the future than if radar observations weren’t available.
'Fly Me to the Moons' -- a view of the Moon with Jupiter and the four Galilean moons, along with a passing airplane. Credit and copyright: Greg Gibbs.
“No matter how much you plan and prepare,” said photographer Greg Gibbs, “sometimes you just have to be very lucky.”
As we mentioned last week, Jupiter and the Moon were going to have a close encounter in the sky on February 18, with an occultation visible in some areas. And so Gibbs was preparing to get shots of the occultation through his telescope from his location in Victoria, Australia, and was using an automated timer to get shots at about 10 second intervals But then he noticed lights from a plane coming close to the Moon.
“I realised that there was a chance that it would pass in front of the Moon,” he said, “so I quickly canceled the remote timer I was using to take the shots and instead started shooting high speed continuous frames. I managed to get this plane crossing the moon in five individual frames just as Jupiter was about to be occulted by The Moon.”
This final product, as Gibbs notes on his Facebook page, is a two image composite. The Moon, Jupiter and the plane are all one single image. Then he took an overexposed image to bring up the Galilean Moons of (from left to right) Io, Callisto and Europa. At the time of this shot, Ganymede had already been occulted by The Moon.
There’s the old saying, “If you can’t be good, be lucky…”
This shot may have been lucky, but it sure is good, too!
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Today at about 9:45 a.m. EST (15:45 UTC) the International Space Station experienced a loss of communication with the Mission Control in Houston, and at this writing, communication has yet to be re-established. When communication was lost, flight controllers in Houston were updating the software onboard the station’s flight computers, and one of the station’s data relay systems malfunctioned. The primary computer that controls critical station functions defaulted to a backup computer, but was not allowing the station to communicate with NASA’s Tracking and Data Relay Satellites, NASA said.
Update: according to the Johnson Space Center Twitter feed, communications have been restored with the space station effective 11:34 am central time (17:34 UTC).
Flight controllers were able to communicate with the crew as the space station flew over Russian ground stations before 11:00 a.m. EST and instructed the crew to connect a backup computer to begin the process of restoring communications. Expedition 34 Commander Kevin Ford reported that the station’s status was fine and that the crew was doing well.
“Hey, just FYI, the station is still flying straight, everybody is in good shape, or course, and nothing unexpected except lots of caution and warning [alarms],” Ford said. “All the systems look like they are doing just fine.” Listen to the recording of his call here.
The loss occurred just prior to NASA TV’s regular broadcast of space station activities, and commentator Brandi Dean said, “We are able to see some data on the ground to let us know that everything is still good on the station and everything is going well with the procedures to re-establish communications with the ground.”
Dean said communication is expected to re-established within an hour, but we’ll provide updates if more problems persist.
In an uncanny coincidence (or prescience), Canadian astronaut Chris Hadfield Tweeted this morning, “Good Morning, Earth! Today we transition the Space Station’s main computers to a new software load. Nothing could possibly go wrong.”
Despite advances in exoplanet research over the past decade much remains unknown. For example, how do the detection rates of giant planets vary as a function of the host star’s metal content? Are giant planets more frequent around massive stars? Do giant planets form under different mechanisms depending on the star’s metal content?
To that end a team of astronomers led by Annelies Mortier and Nuno C. Santos explored what mathematical function characterizes the detection rate across a distribution of stars (i.e., from metal-rich to metal-poor objects). “Finding the exact functional form of the metallicity-planet detection frequency will foster our understanding of both planet formation and the number of planets roaming the galaxy,” Santos told Universe Today.
Giant planets are most often found around metal-rich stars, and a figure from the team’s study (shown below) reaffirms that ~25% of stars featuring twice the Sun’s metal content host a giant planet, while the probability falls to ~5% for stars with a metal content analogous to the Sun.
Establishing that metal-rich stars exhibit an increased probability of hosting a giant planet constrains planet formation models. Specifically, the observations suggest that larger metallicity promotes the growth of rocky/icy cores, which subsequently accrete gas. However, the team notes that although the giant planet-metallicity trend is solid for stars exhibiting metallicities greater than (or analogous to) the Sun, the results are less certain for metal-poor stars. Indeed, there is an active debate in the literature pertaining to what function links the metal-rich and metal-poor regimes. In particular, does an exponential decline extend into the metal-poor regime, or does the function level off?
Depending on the manner in which the frequency trend extends into the metal-poor regime, it may indicate that a separate mechanism is responsible for creating that subsample’s giant planets. Thus continued surveys of metal-poor stars are important, despite the decreased frequency of finding a giant planet. Moreover, Mortier (Centro de Astrofisica, Universidade do Porto) notes that, “Studying metal-poor stars should be encouraged, since several theoretical models show that Earth-like planets are more common around these stars than around their metal-rich counterparts.”
Frequency of giant planets as a function of metallicity (credit: Mortier et al., arXiv 1302.1851).
The team focused their efforts on trying to discern a difference between the viability of various functional forms in the metal-poor regime (i.e., does the detection rate of giant planets in that domain flatten, rather than decline exponentially?). In the end no statistical difference was found between the scenarios, and it was likewise unclear whether a mass-dependence exists behind the frequency of giant planet detections. The team noted that a larger sample was needed to reach definitive conclusions, and added that ongoing surveys to discover planets would ensure the problem may soon be resolved.
“Kepler and Gaia will significantly increase the amount of planet discoveries, not only for giant planets, but also for smaller planets,” said Mortier.
In sum, to answer the questions posed at the outset planet-hunting efforts should be focused on metal-poor and metal-rich stars, despite the former exhibiting a reduced frequency of giant planets. The team’s findings will appear in Astronomy & Astrophysics, and a preprint is available on arXiv. The results from the study are tied in part to observations acquired via the HARPS (High Accuracy Radial Velocity Planet Searcher) instrument, which is shown below.
Comet L4 Panstarrs photographed from Australia at dawn on Feb. 17, 2013 with a telephoto lens. A bright head and short tail are visible. Credit: Joseph Brimacombe
2013 could turn out to be a comet bonanza. No fewer than three of these long-tailed beauties are expected to brighten to naked eye visibility. Already Comet C/2011 L4 PANSTARRS has cracked that barrier. Sky watchers in Australia have watched it grow from a telescopic smudge to a beautiful binocular sight low above the horizon at both dusk and dawn. A few have even spotted it without optical aid in the past week. Excited reports of a bright, fan-shaped dust tail two full moon diameters long whet our appetite for what’s to come.
Recent brightness estimates indicate that the comet could be experiencing a surge or “second wind” after plateauing in brightness the past few weeks. If the current trend continues, PanSTARRS might reach 1st or 2nd magnitude or a little brighter than the stars of the Big Dipper when it first becomes visible to northern hemisphere sky watchers around March 7. That’s little more than two weeks away!
Comet Panstarrs will make its first appearance for northern hemisphere sky watchers around March 7 low in the western sky after sundown. Notice that the comet gets no higher than 10 degrees – about one fist held at arm’s length – through much of the month. Illustration created using Chris Marriott’s SkyMap software
Every day between now and March 10, when PanSTARRS’ orbit takes it closest to the sun, the comet is expected to slowly increase in brightness. Later this month it disappears in the solar glare, but when it re-emerges into evening twilight around Thursday, March 7, northern and southern hemisphere observers alike will get great views. Binoculars should easily show a bright head and swept-back tail pointing away from the sun. And don’t forget to mark your calendar for March 12. On that date the thin lunar crescent will join the comet for a rare photogenic pairing. To locate and keep track of PanSTARRS, you’ll need the following materials and circumstances:
* An unobstructed view of the western horizon
* Clear, haze-free skies at dusk
* Pair of binoculars
* A map
I can’t help you with all of the above, but this map will help point you in the right direction. Once you find a location with a great western view, watch just above the horizon for a fuzzy, star-like object in your binoculars. While it’s possible the comet will be bright enough to see with the naked eye, binoculars will make finding it much easier. They’ll also reveal details of tail structure too subtle to be visible otherwise.
Incredible detail is seen in the gas tail of F6 Lemmon in this photo made with a 19.6-inch telescope Feb. 17, 2013. Credit: Martin Mobberley
Comet PanSTARRS has some cometary company. C/2012 F6 Lemmon is currently plying its way through the constellation Tucana the Toucan, shining right around the naked eye limit at magnitude 5.5. To the unaided eye, Lemmon looks like a dim fuzzy spot. Binoculars show a thin gas tail and big, bright head or coma. Comas develop around the comet’s icy nucleus as sunlight vaporizes dusty ice to create a short-lived atmosphere that in the shape of a luminous teardrop. Long-exposures like the one above reveal richly-detailed streamers of carbon monoxide and other gases fluorescing in sunlight in the comet’s fashionably skinny tail.
Lemmon is slowly receding from Earth this month, but should remain just above the naked eye limit for some time as it continues to approach the sun. Northern hemisphere observers will need to be patient to see this one. After looping around the sun on March 24, the comet will pop back into the morning sky near the familiar Square of Pegasus asterism in early May. If we’re lucky, Lemmon may still be near the naked eye limit and visible in ordinary binoculars.
Cmet C/2012 F6 (Lemmon), imaged on Feb. 19. 2013 remotely from Q62 (iTelescope Observatory, Siding Spring). Credit: Ernesto Guido and Nick Howes, Remanzacco Observatory.
Before we move on to the comet with the greatest expectations, I want to mention Comet 2P/Encke. Encke was the only the second comet to have its orbit computed – way back in 1819 by German astronomer Johann Encke. This year it’s making its 62nd observed return to Earth’s vicinity. That’s a lot of visits, but when your orbital period is only 3.3 years – the shortest known of any comet – you can’t help but be a regular visitor. While not expected to brighten to naked eye level, the comet will be a fine sight in modest-sized telescopes glowing around 8th magnitude when it tracks between the Big Dipper and Leo the Lion this October.
Comet ISON in the western sky shortly after sunset in late November this year. Illustration created with Chris Marriott’s SkyMap software
Our final comet, Comet C/2012 S1 ISON, was discovered last September by Russian amateurs Vitali Nevski and Artyom Novichonok while making observations for the International Scientific Optical Network(ISON). At the time, it was farther than Jupiter and impossibly faint, but once ISON’s orbit was determined, astronomers realized the comet would pass only 1.1 million miles from center of the sun (680,000 miles above its surface) on November 28, 2013.
Comet ISON belongs to a special category of comets called sungrazers. As the comet performs a hairpin turn around the sun on that date, its ices will vaporize furiously in the intense solar heat. Assuming it defies death by evaporation, ISON is expected to become a brilliant object perhaps 10 times brighter than Venus. Or brighter. Some predict it could put the full moon to shame. If so, that would occur for a brief time around at perihelion (closest approach to the sun) when the comet would only be visible in the daytime sky very close to the sun. When safely viewed, ISON might look like a brilliant, fuzzy star in a blue sky.
A color image of comet Ison taken on February 5, 2013 from northern Arizona. Credit: Chris Schur.
Most of us won’t risk burning our retinas staring so close to sun. Instead we’ll watch with anticipation as the comet sprouts a long tail while ascending from the western horizon just after sunset in late November and early December. Whatever it does, sky watchers in both southern and northern hemispheres will ringside seats when ISON’s at its best.
Right now the comet’s whiling away its time in the constellation Gemini the Twin and still very faint. Come September, it should be easily visible in small telescopes in the morning sky. The first naked eye sightings could happen in late October. Many of us hope the comet will be one for the record books, a worthy successor to C/2006 P1 McNaught, the last “great comet” to dazzle human eyes. It reached peak magnificence for southern hemisphere sky watchers in January 2007.
C/2006 P1 McNaught became a memorable sight for observers living in southern latitudes in January 2007. Will Comet ISON do the same? Credit: Wikipedia
Three bright comets – and one modestly bright – might be enough for a year, but there could be surprises. Dozens of new comets are discovered each year by professional sky surveys and amateur astronomers. Most are faint and move along their appointed paths unnoticed by 99.9% of the world’s population, but every so often a new one comes along that blossoms into a spectacle. How many of those are out there tonight waiting to be discovered?
Expedition 24's Tracy Caldwell Dyson gazes out of the cupola. Credit: NASA
There’s a panoramic window on the International Space Station named after the observation decks that old-time train cabooses had.
The Cupola, as it’s known, includes six side windows and a big one in the center. An astronaut floating nearby can see 1,000 km of Earth below him or her. It’s the ultimate spot to keep an eye on a hurricane, or provide guidance to a crewmate wrestling the robotic Canadarm2 towards an incoming spacecraft.
Hard to believe it’s been three years since the astronauts on STS-130 installed it in February 2010. Below, check out the best of astronaut photography of or from the Cupola since that time.
From the outside, the cupola looks like a flying saucer. That’s Douglas Wheelock (Expedition 25) inside the window. Credit: NASAA green tint from an aurora is seen out the Cupola over the southern Indian Ocean. Credit: NASACanadarm2 makes some moves towards Japan’s robotic H-II Transfer Vehicle (HTV-3) during Expedition 32. Credit: NASAThe Cupola provides a portal to 215 million years in the past: The Manicouagan impact crater in northern Québec shows up nearly in the center of the main Cupola window. Credit: NASAThe STS-131 crew somehow organizes themselves on the small window in microgravity. Pictured are Commander Alan Poindexter, Pilot James P. Dutton Jr. and Mission Specialists Dorothy Metcalf-Lindenburger, Rick Mastracchio, Naoko Yamazaki, Clayton Anderson and Stephanie Wilson. Credit: NASANASA astronaut Ron Garan looking down at a night view of Australia from the International Space Station’s cupola..An Expedition 27 crewmember captured this cyclone over the north Pacific. Told you it’s a good view. Credit: NASAThe end effector — or grappler — at the end of the Space Station’s Canadarm 2 robotic arm is visible out the main window of the Cupola, with a view of our beautiful blue planet below. Credit: NASA.STS-130’s Nicholas Patrick casually hanging out beneath the cupola after helping install it. Credit: NASA
There have also been some stunning filmed timelapses from the Cupola, such as this one:
Color map of Mercury's varied surface. The 1,550-km-wide Caloris Basin can be seen at upper right.
Created by the MESSENGER mission team at the Johns Hopkins University Applied Physics Laboratory and the Carnegie Institution of Washington, this animation gives us a look at the spinning globe of Mercury, its surface color-coded to reflect variations in surface material reflectance.
Thousands of Wide Angle Camera images of Mercury’s surface were stitched together to create the full-planet views.
While the vibrant colors don’t accurately portray Mercury as our eyes would see it, they are valuable to scientists as they highlight the many different types of materials that make up the planet’s surface. Young crater rays surrounding fresh impact craters appear light blue or white. Medium- and dark-blue “low-reflectance material” (LRM) areas are thought to be rich in a dark, opaque mineral. Tan areas are plains formed by eruption of highly fluid lavas. Small orange spots are materials deposited by explosive volcanic eruptions.
At this point, over 99% of the Solar System’s innermost planet has been mapped by MESSENGER. Read more about the ongoing mission here.
Image/video credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Composite Image of NGC 5189 Courtesy of Robert Gendler
Stretching across three light years of space and located about 3,000 light years away in the direction of the constellation of Musca, an incredible and rather understudied planetary nebula awaits a new hand to bring out new light. While most planetary nebula have a rather normal, bloated star look, NGC 5189 shows an extraordinary amount of loops and curls not normally seen in objects of its type. Just what is going on here?
This incredibly detailed image comes from the one and only Robert Gendler and was assembled from three separate data sources. The detail for the nebula is from Hubble Space Telescope data, the background starfield from the Gemini Observatory/AURA and the color data from his own equipment. Here we see fanciful gas clouds with thick clumps decorating them. Intense radiation and gas streams from the central dying star in waves, fashioning out hollows and caves in the enveloping clouds. While these clumps in the clouds may appear as wispy details, each serves as a reminder of just how vast space can be… for each an every one of them is about the same size as our Solar System.
“The complex morphology of this PN is puzzling and has not been studied in detailed so far. Our investigation reveals the presence of a new dense and cold infrared torus (alongside the optical one) which probably generated one of the two optically seen bipolar outflows and which might be responsible for the twisted appearance of the optical torus via an interaction process.” says L. Sabin (et al). ” The high-resolution MES-AAT spectra clearly show the presence of filamentary and knotty structures as well as three expanding bubbles. Our findings therefore suggest that NGC 5189 is a quadrupolar nebula with multiple sets of symmetrical condensations in which the interaction of outflows has determined its complex morphology.”
And just as incredibly large as some things can be – others can be as small. At the heart of NGC 5189 shines the tiny light of its central star… no bigger than Earth. It wobbles its way through time, rotating rapidly and spewing material into space like a runaway fire hydrant. Astronomers speculate there might be a binary star hidden inside, since usually planetary nebulae of this type have them. However, only one star has been found at the nebula’s center and it might be one very big, very bad wolf.
“Around 15% are known or suspected binaries, while the remaining 18% are non-emission line nuclei which require further study. Selecting for LIS (low ionization structures) therefore will give a mix of mostly binary and emission line nuclei which will require further observations to separate.” explains B. Miszalski (et al). “Almost all the [WR] CSPN in the sample belong to the hot [WO] type that have more extreme and chaotic LIS covering their entire nebulae, presumably due to turbulence from the strong [WR] winds disrupting pre-existing LIS.”
Just why is this celestial tapestry so complicated and complex? The answer isn’t a simple one – it’s one that has many plausible theories. We know that when a star similar to the Sun expends its fuel, it will begin to shed its outer layers… layers which normally take on very basic shape. These “normal” shapes are usually a sphere, sometimes a double lobe and at times it can be a ring or helix. However, NGC 5189 just doesn’t follow rules. Over time, researchers have speculated it has given off different outlfows at different stages – one prominent as a very visible torus situated around mid-point in the structure – consistent with the theory of a binary star system with a precessing symmetry axis. Still, there is clearly more research needed.
“Our preliminary results of a comparative spectroscopic study of these two objects shows that the chemical composition of the two nebulae is completely different, even though their morphology is most probably quite similar.” says VF Polcaro (et al). ” In addition, the PN appears much more chemically homogeneous. These features are clearly associated with the evolutionary paths of the stars.”
“The striking broad emission line spectroscopic appearance of Wolf-Rayet (WR) stars has long defied analysis, due to the extreme physical conditions within their line and continuum forming regions.” explains Paul Crowther. “Theoretical and observational evidence that WR winds depend on metallicity is presented, with implications for evolutionary models, ionizing fluxes, and the role of WR stars within the context of core-collapse supernovae and long-duration gamma ray bursts.”
Is NGC 5189 the handiwork of a binary star? Or is it the product of an intensely hot Wolf-Rayet? Like the proverbial Tootsie Pop equation… the world may never know.
Many thanks to Robert Gendler for sharing this incredible image with us.
