Comet C/2011 L4 PANSTARRS on May 21, 2013, when its anti-tail had grown to more than 12 full moons in length. The original main tail of the comet - to the right of the head - has faded and shortened. Credit: Damian Peach
While comets can’t tell lies, they do sometimes grow long noses. As the weeks click by and our perspective on Comet L4 PANSTARRS changes, its original plume-like dust tail has shrunk and faded while a second tail just won’t stop growing.
Comet PANSTARRS’ orbital plane slices (marked by gray lines) slices right through the plane of the planets. Earth crosses that orbital plane on May 27. As we look up into space at the comet (blue arrow), all the dust it shed along its path – including a fine sheet of particles – stacks up to create a narrow, streak-like tail pointing toward the sun. The shorter, active dust tail sticks up and away (top). Credit: NASA with my own additions
I’m talking about the anti-tail, so called because it points toward the sun instead of away. Like the normal dust tail, an anti-tail is formed from fresh dust blown back from the comet’s head by the pressure of sunlight. As the comet continues along its orbital path, last week’s dust lingers behind, forming a “trail of breadcrumbs” in its wake. Right now those breadcrumbs look like a light saber straight out of Star Wars. Time exposure photographs show a striking sunward-pointing appendage more than 6 degrees (12 full moons) long. I’ve been keeping an eye on Comet PANSTARRS here at home and can report that the anti-tail is plainly visible with a telescope under dark skies. Watching it grow from a short nub to the most dominant feature of this remarkable object has been the highlight of many a clear night.
Our current “edge on” view of Comet PANSTARRS is similar to looking down on it from high above the Earth’s north pole, where the dust stacks up to create a bright, streak-like tail. Credit: NASA/JPL/my own additions
Nothing stands still in our solar system. Earth’s moving, the comet’s moving. Later this week on May 26-27, Earth will pass directly through the comet’s orbital plane, which slices through the plane of the planets at a very steep angle. As the Earth approaches this intersection, we look up (from the northern hemisphere) and stare squarely into the long trail of dusty debris deposited by PANSTARRS during its recent swing around the sun in March. It gets better.
If we step back in time to May 9, we see that the anti-tail was neither as long nor as pronounced because the Earth was further from the comet’s orbital plane. Because we were more broadside to the comet then, the dust sheet is much more obvious. It extends millions of miles into space but is only 5,000-10,000 miles thick. Credit: Michael Jaeger
Sunlight pushes the smaller particles into a vast, thin sheet or fan extending millions of miles into space well beyond the path traveled by the comet’s nucleus. Since we now see PANSTARRS almost “edge-on”, all that dust overlaps from our perspective to form a thick, bright line sticking out of the comet’s head. It’s as if we’re seeing the ghost of PANSTARRS from the recent past still lingering in space. If we could somehow see the whole works broadside, the comet would appear fainter, spread out and much more diffuse.
Simulated views of dust shed by PANSTARRS’ in its orbit around the sun. Dust piles up in the edge-on view to create a skinny, saber-like tail vs. a faint, broad tail (right). Illustration: Bob King
The Milky Waystands out as a band of light distinct from the thin scree of stars for the very same reason; our gaze cuts edge-on through our galaxy’s flattened disk where stars are most concentrated. Like comet dust, they pile atop one other to create a distinct ribbon of fuzzy light slicing across the night sky.
Going back even further to April 10, the anti-tail (short stub to left of bright head) was just getting started. It’s completely dwarfed by the comet’s main dust tail and fan of tinier dust particles. Compare this photo to the current view. Click to enlarge. Credit: Michael Jaeger
In the next few days the tail could grow considerably longer and intensify in brightness as we move closer to the comet’s orbital plane. Unfortunately the moon will be at or near full at the same time, making it tougher to fully appreciate this amazing apparition at least with binoculars and telescopes. Cameras will have better luck. Will that stop you from looking? I hope not. Either way, you can use this map to help you find Comet PANSTARRS and check it out yourself.
Map showing Comet C/2011 L4 PANSTARRS’ location tonight through June 21. Positions are marked off every three nights with stars are shown to about 8th magnitude. Credit: created with Chris Marriott’s SkyMap software
When you do spot the anti-tail, don’t be fooled. It may appear to be pointing at the sun, but it’s only dust spread along a path once tread.
A magnificent view of the very thin anti tail of Comet PANSTARRS, as seen on May 22, 2013 from near Payson, Arizona. Credit and copyright: Chris Schur.A negative image showing Comet PANSTARRS and its very thin anti tail, as seen on May 22, 2013 from near Payson, Arizona. Credit and copyright: Chris Schur.
We at Universe Today have been wondering, where did Chris Hadfield find the time to do all the greatvideos he put together during his five months on the International Space Station, all while his Expedition set records for the amount of scientific research performed? Now there’s even more. Hadfield teamed up with Jamie Hyneman and Adam Savage of Mythbusters fame, who now are part of the Tested crew, too, to produce three different videos about living in space; specifically about eating and what to do with any free time astronauts might have.
“Working with Adam and Jamie was fun!” Hadfield said via Twitter. “Mutual mustache appreciation.”
In the video above, Jamie and Adam learn about Chris Hadfield’s clever “space darts” invention, and propose a new game for Hadfield to test while he’s on orbit. Spoiler: duct tape is involved.
Making medical diagnoses aboard Space Station can be a tricky business (Image: NASA)
Even though astronauts receive some general medical training in preparation for a stay aboard the ISS, most of them still aren’t medical professionals by any means — and with the inherent difficulties of microgravity and the relatively noisy environment inside the Station, even a simple diagnostic task like listening to a heartbeat can be a challenge.
That’s why engineering students at Johns Hopkins University have developed a special “out of this world” space stethoscope designed to work well while in orbit… as well as down here on Earth.
Space is serene because no air means no sound. But inside the average spacecraft, with its whirring fans, humming computers and buzzing instruments, it can be as raucous as a party filled with laughing, talking people.
“Imagine trying to get a clear stethoscope signal in an environment like that, where the ambient noise contaminates the faint heart signal. That is the problem we set out to solve,” said Elyse Edwards, a senior from Issaquah, Wash., who teamed up on the project with fellow seniors Noah Dennis, a senior from New York City, and Shin Shin Cheng, from Sibu, Sarawak, Malaysia.
Components for a space stethoscope (Photo: Will Kirk/homewoodphoto.jhu.edu)
The students worked under the guidance of James West, a Johns Hopkins research professor in electrical and computer engineering and co-inventor of the electret microphone used in telephones and in almost 90 percent of the more than two billion microphones produced today.
Together, they developed a stethoscope that uses both electronic and mechanical strategies to help the device’s internal microphone pick up sounds that are clear and discernible – even in the noisy spacecraft, and even when the device is not placed perfectly correctly on the astronaut’s body.
“Considering that during long space missions, there is a pretty good chance an actual doctor won’t be on board, we thought it was important that the stethoscope did its job well, even when an amateur was the one using it,” Dennis said.
The device also includes many other performance-enhancing improvements, including low power consumption, rechargeable batteries, mechanical exclusion of ambient noise and a suction cup, so that it sticks firmly onto the patient’s chest, says Cheng.
Though developed for NASA’s use in outer space, this improved stethoscope could also be put to use here on Earth in combat situations, where ambient noise is abundant, and in developing countries, where medical care conditions are a bit more primitive.
West also plans to use the device to record infants’ heart and lung sounds in developing countries as part of a project that will attempt to develop a stethoscope that knows how to identify the typical wheezing and crackling breath sounds associated with common diseases.
Neil deGrasse Tyson’s new book, Space Chronicles: Facing The Ultimate Frontier, at times, reads like an updated version of some of Carl Sagan’s classic work about the history of astronomy and our place in the Universe. You can read our full review of Tyson’s new book here, but we also have two free copies of this book to give away.
In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Tuesday, May 28 2013. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing.
But if you are feeling unlucky, then you can buy the book from Amazon.
For those fans of Carl Sagan’s Pale Blue Dot, there’s finally a successor volume to that.
Neil deGrasse Tyson’s Space Chronicles: Facing The Ultimate Frontier, at times, reads like an updated version of Sagan’s classic book about the history of astronomy and our place in the universe. Like Sagan, Tyson talks about the human perception of astronomy over the years, starting from our belief that everything centered around us and then gradually graduating to the more nuanced perception of the universe that we have today.
The book is an anthology of interviews, magazine articles and other writings of Tyson, who is currently the director of the Hayden Planetarium at the American Museum of Natural History in New York. His eloquence helps carry the reader through difficult concepts: “Engineering technology replaces muscle energy with machine energy”, he writes in part of the Industrial Revolution. In another part of the book, “Risks cancellations and failures are just part of the game” comes during an explanation of how some astronomical missions die before receiving funding from Congress.
Collecting his writings as an anthology, however, leads to some frustration for the reader who wants to read the book from the front to the back. Though Tyson awes with his knowledge of astronomy, popular culture and history, he sometimes uses the same anecdotes across different essays. There are at least three references concerning gas stations across the universe, for example, and he refers to the same John F. Kennedy speech (albeit different passages, for the most part) a few times as well.
The book is also aimed squarely at an American audience. The appendices are full of useful information on NASA, particularly its budget as it relates to government activities. Additionally, Space Chronicles opens with a new essay concerning NASA funding over the years and how it relates to American presidencies in a sort of echo of Spaceflight and the Myth of Presidential Leadership.
Tyson argues that space is non-partisan and that it takes more than a strong leader to move the program forward. Tyson criticizes NASA for de-emphasizing science in some of its past budgets. He refers to the controversy of Obama’s cancellation of George W. Bush’s 2004 vision for space exploration, and says one great weakness of NASA’s work is that it is continually handed mandates by new presidents with little follow-up on the grand ideas.
Through the book, Tyson talks about his ideas for NASA, mentioning initiatives such as asteroid tracking as high priorities. He also refers to the space committees he has been on and the people he has spoken to, and his efforts to bring space to children to encourage their participation in science, education, technology and mathematics.
Perhaps his most powerful essay comes at the end of the book. Tyson acknowledges the nature of his work sometimes makes him forget about Earthly problems: “When I pause and reflect on our expanding universe … sometimes I forget that uncounted people walk this Earth without food or shelter, and that children are disproportionately represented among them.”
That dilemma may never disappear, but Tyson’s book — at the least — provides powerful words for exploring the universe.
Recent Sun Pillar seen near Toronto, Canada. Credit and copyright: Rick Ellis.
Astrophotographer Rick Ellis from Toronto, Canada recently imaged a Sun pillar against a truly fiery sunset. Sun pillars are a vertical shaft of light extending upward or downward from the Sun, usually seen during sunrise or sunset. They form when sunlight reflects off the surfaces of high-altitude hexagonal-shaped or flat ice crystals. The crystals are typically associated with thin, high-level clouds, such as cirrostratus clouds. “Fire and ice,” Rick said via email. “Robert Frost would approve.”
Rick used a Canon A460, 1/100 seconds exposure at f/3.5, ISO 80.
And here’s Robert Frost’s famous poem:
FIRE AND ICE
by Robert Frost
Some say the world will end in fire,
Some say in ice.
From what I’ve tasted of desire
I hold with those who favor fire.
But if it had to perish twice,
I think I know enough of hate
To say that for destruction ice
Is also great
And would suffice.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.
Satellite Image of Oklahoma Tornado. Acquired at 2:55 CT on May 20, 2013, this image from the NOAA GOES-13 satellite shows the storms developing directly over central Oklahoma. One minute later an incredibly destructive tornado touched down in Moore, OK. Credit: NOAA.
The massive tornado that tore through parts of Oklahoma on My 20, 2013 left a 32 km (20-mile) swath of destruction and death, with winds approaching 320 km/hr (200 mph). The US National Weather Service said the 3 km (2-mile)-wide tornado spent 40 minutes on the ground in the area of Moore, Oklahoma, outside of Oklahoma City, destroying schools, a hospital and hundreds of homes, killing dozens of people. Satellite images and video show how the storm developed.
Below is a video showing satellite imagery from the GOES 13 satellite from May 19-20, 2013. It shows the tornado outbreak and supercell thunderstorms that developed across portions of the Great Plains:
Weather satellites help scientists to observe weather patterns from the unique vantage point of space. This provides the ability to see a larger area of the Earth rather than with conventional radar which does not reveal a true overview of cloud structure and wind patterns.
These satellites can measure many different things, such as in the image below, which looks at water vapor content of the clouds. The satellites operated by NASA and NOAA and are equipped to send back images in infrared and other wavelengths, providing snapshots of things like the water vapor measurements, temperatures, wind patterns, cloud coverage, storm movement and many other readings. This information also helps with the prediction of storms, allowing for warnings for people to seek shelter from potentially destructive weather events.
This screenshot shows a false color view of the water vapor content in the clouds during the tornado outbreak in Oklahoma on May 20, 2013, as seen from NOAA geostationary (GOES) satellites. Click on image to go to current NOAA imagery.
The news from Oklahoma is ongoing, and we encourage you to keep current on the latest information from other news sites. But as Phil Plait pointed out, if you are interested in helping the people involved in this tragedy, the Take Part website has a list of organizations that are in the area providing support.
This full-disk view of Earth shows the formation of the Oklahoma tornado, from the Aqua satellite. Credit: NASA Goddard Space Flight Center.
As the first eclipse season of 2013 comes to an end this weekend, an extremely subtle lunar eclipse occurs on the night of Friday, May 24th going into the morning of Saturday, May 25th. And we do mean subtle, as in invisible to the naked eye… this eclipse only lasts 34 minutes in duration and less than 2% of the disk of the Moon enters the bright outer penumbra of the Earth’s shadow!
So, why talk about such a non-event at all?
Great things come from such humble beginnings. And while this weekend’s eclipse is one mostly for the almanacs and astronomical tables rather than a true observational event, it also marks the start of a new lunar saros cycle.
This weekend’s eclipse is one of five for 2013, a year which contains two solars and three lunars. This eclipse marks the end of the first “eclipse season” of the year, a time when the intersection of the Moon’s orbit (known as nodes) and the ecliptic nearly coincide with the position of the Sun (for a solar eclipse at New Moon) and the Earth’s shadow (for a lunar eclipse at Full Moon).
The current season began with a very slight partial eclipse on April 25th, followed by an annular eclipse on May 10th. It will last only 33 minutes and 45 seconds in duration starting at 03:53:11 UTC on May 25th. The Moon will be high over the Americas at the time, but again, shading on the southern limb of the Moon will be too slight to be seen.
Curiously, SLOOH will be providing live coverage of the eclipse, although again, it will be too slight to see.
The Full Moon just nicks the Earth’s penumbra in the early morning hours of May 25th. (Created by the author in Starry Night).
What is a saros? A saros is a period of 18 years 11 days and 8 hours after which an eclipse cycle lines up, producing a similar eclipse to the one that preceded it 18 years before. Note that due to its 8 hour offset, the Earth will have rotated 120° and the visibility region will have shifted westward.
In said period, three lunar cycles very nearly line up;
The Anomalistic month (the period the Moon takes to go from one perigee to another) = 27.555 days.
The Draconic month (the period the Moon takes to return to the same node) = 27.212 days.
The Synodic month (the most familiar one, the period between similar phases) = 29.531 days.
There’s that mis-alignment of a third of a day again (8 hours) for every 18 years and 11 days. This also causes the node of each eclipse in the cycle to drift eastward by 0.5° along the ecliptic. Thus, each eclipse isn’t exactly the same. A lunar saros series starts with a very brief penumbral like this weekend’s, becomes deeper and deeper every 18+ year period until partial and total eclipses begin centuries down the road. Thereafter, the cycle reverses, until a final faint penumbral marks the end of the lunar saros.
The progression of selected eclipses of the same saros cycle. (Credit: Matthew Zimmerman. Wikimedia Commons graphic in the Public Domain).
After this weekend’s eclipse, the next start of a lunar saros won’t occur until November 8th 2060 with the start of saros 156. The last new saros series (number 149) began on June 13th, 1984.
There are numbered saros series for both lunar and solar eclipses. There are currently 41 saroses (the plural of saros) active with the inclusion of this weekend’s start of lunar saros 150.
Saros 150, of which this eclipse is the 1st of 71, will last for just over 1,262 years. It will begin to produce partial eclipses on August 20th, 2157 and produce its 1st total on its 32nd lunar eclipse on April 29th, 2572.
It amazes me that ancient cultures such as the Chaldeans new of saros cycles and could predict eclipses. Being geographically isolated, lunar eclipse cycles would have been easier to decipher than solar ones, as you only have to be on the Moonward facing hemisphere of the Earth to witness the eclipse. They may well have stumbled upon the saros while attempting to calculate a slightly longer 19 year period known as a Metonic cycle to align ancient luni-solar calendars.
And yes, that 8 hour offset also means that after a triple saros period, lunar and solar eclipses of the same saros series do return to roughly the same longitude every 54 years & 34 days. This is known as an exeligmos, and if you get this on a triple-word score in Scrabble, you can safely retire from the game.
The theoretical visibility circumstances for this week’s penumbral eclipse. (Credit: F. Espenak/NASA/GSFC).
And while this eclipse is more of academic than observational interest, you can always enjoy the light of a brilliant Full Moon. The May Full Moon is referred to as the Flower, Milk, and Corn Planting Moon by the Algonquian Indians of North America, alluding the latent season of Spring.
Also, keep an eye out for several conjunctions and occultations this week by the Moon with bright stars and planets.
The first up is the bright star Spica (Alpha Virginis) which gets occulted by the waxing gibbous Moon around ~11:00 UT on Wednesday, May 22nd for viewers across northern Australia, southern Asia and the South Pacific. Spica is one of four stars brighter than magnitude +1.5 that the Moon can occult, the others being Antares, Aldebaran and Regulus. This is the 6th occultation in a cycle of 13 of Spica by the Moon spanning 2013.
The planet Saturn will lie about 4° north of the waxing gibbous Moon on the following evening of May 23rd.
Also, watch for an occultation of the +2.6th magnitude star Beta Scorpii on the evening of May 24th around the time of the lunar eclipse. This will be a difficult one, as the Moon will be near 100% illumination. Conjunction of the Moon and Beta Scorpii in right ascension occurs at 3:04 UT on May 25th, about 2.5 hours after Full. The occultation will span the southeastern US, Caribbean, northern South America and western Africa.
Visibility path of the occultation of Beta Scorpii by the Moon. (Credit: Occult 4.1.0.2).
2013 isn’t a grand year for eclipses. We’ve got two more in the late season of the year, another slightly deeper penumbral on October 18th and a hybrid solar eclipse on November 3rd. And when, may you ask, will we FINALLY have another total lunar eclipse? Stick around ‘til U.S. Tax Day next year (April 15th 2014) for a total lunar eclipse spanning the Americas!
Artist's conception of the solar system, often used in the Eyes on the Solar System 3D Simulator. Credit: NASA
Venus and Mars may be all right tonight, but there’s still a lot we don’t understand about these planets. Why does one, Venus, have such a thick atmosphere? Why is that of Mars so thin? And why is Earth’s atmosphere so different again from what we see on Venus and Mars?
A new JAXA (Japan Aerospace Exploration Agency) satellite aims to better understand what’s going on. It’s called SPRINT-A, for Spectroscopic Planet Observatory for Recognition of Interaction of Atmosphere.
JAXA has set an official launch date of Aug. 22 from the Uchinoura Space Center, although the window extends as far as Sept. 30. (Launches can be delayed due to weather and mechanical difficulties.) The satellite’s expected Earth orbit will range from 590 to 715 miles (950 to 1150 kilometers) above the planet.
“Venus and Earth may be called twin planets, and it recently becomes clear that three terrestrial planets in the solar system – including Mars – have very similar environments in the beginning era of the solar system,” JAXA stated in a press release.
Earth’s atmosphere was similar to that of Venus and Mars in the early solar system, but now it’s quite different, says JAXA. (Image: NASA/Suomi NPP)
The agency pointed out, however, that these three planets ended up with different fates. Venus has a runaway greenhouse effect on its planet, with surface temperatures reaching a scorching 752 degrees Fahrenheit (400 degrees Celsius). Mars, on the other hand, has a very thin atmosphere and more variable temperatures that can get a little chilly.
Understanding how atmospheres escape into outer space is the main goal of SPRINT-A. The sun, the scientists stated, had more intense activity in the past than what we see presently, which could have blown away the atmosphere on some terrestrial planets.
“The study on interaction of the strong solar wind on the atmosphere of the planet leads to acquiring knowledge of history in the early stage of the solar system,” JAXA stated.
Besides looking at the inner solar system, SPRINT-A will investigate a phenomenon related to a splotchy volcanic moon orbiting the planet Jupiter.
Io, a moon of Jupiter. The colors in this image have been enhanced to better show differences. Sulfur dioxide frost appears in white and grey, and other types of sulfur are in yellow and brown. Recent volcanic activity is marked by red and black blotches. Credit: NASA
SPRINT-A aims to better understand a ring of material surrounding Jupiter that came from Io.
Electrons and ions from the volcanic moon surround Jupiter and, as they collide, produce ultraviolet light in a process similar to what causes auroras in the upper atmosphere of Earth and other planets. How this happens is still being figured out, though.
It’s a pretty radiation-heavy environment in that region of the solar system. The spacecraft Galileo safely orbited the Jovian moons for years, but humans would have a little more trouble surviving the radiation without heavy shielding and careful precautions.
