Universe Today

April 29, 2014December 23, 2015 by Shannon Hall

It’s Freezing on the Surface of this Nearby Star-like Object

This artist's conception shows the object named WISE J085510.83-071442.5, the coldest known brown dwarf. Image credit: Penn State University/NASA/JPL-Caltech

Our stellar neighborhood just got a little busier … and a little colder.

A brown dwarf that’s as frosty as the Earth’s North Pole has been discovered lurking incredibly close to our Solar System. Astronomer Keven Luhman from Pennsylvania State University used NASA’s Wide-field Infrared Survey Explorer (WISE) and the Spitzer Space Telescope to pinpoint the object’s temperature and distance. This is the coldest brown dwarf found so far, and it’s a mere 7.2 light-years away, making it the seventh closest star-like object to the Sun.

“It is very exciting to discover a new neighbor of our Solar System that is so close,” said Luhman in a press release.

Brown dwarfs emerge when clouds of gas and dust collapse. But unlike stars, they never grow dense enough or burn hot enough to ignite nuclear fusion in their cores. They live their lives less massive than stars, but more massive than gas giants. So they burn hot at first, then cool over time. And this newly discovered brown dwarf is as cold as ice. Literally.

WISE surveyed the entire sky twice in its short 14-month lifetime, looking at cooler objects, which radiate in infrared light (but often remain invisible in visible light). It saw cold asteroids, dust clouds, proto-planetary disks, distant galaxies and hundreds of brown dwarfs.

But one of these objects — dubbed WISE J085510.83-071442.5 — was moving rapidly, suggesting it was extremely close to the Solar System. All stars orbit around the Milky Way, with apparent motions seen on the timescale of hundreds of years. Stars close to the Sun, however, can be seen to make the slightest of movements on the timescale of just a few years. This object appeared to move in just a few months.

This animation shows the coldest brown dwarf yet seen, and the fourth closest system to our sun. Called WISE J085510.83-071442.5, this dim object was discovered through its rapid motion across the sky. It was first seen in two infrared images taken six months apart in 2010 by NASA's Wide-field Infrared Survey Explorer, or WISE (see orange triangles). Two additional images of the object were taken with NASA's Spitzer Space Telescope in 2013 and 2014 (green triangles). All four images were used to measure the distance to the object -- 7.2 light-years -- using the parallax effect. › See animation The Spitzer data were used to show that the body is as cold as the North Pole (or between minus 54 and 9 degrees Fahrenheit, which is minus 48 to minus 13 degrees Celsius). Image credit: NASA/JPL-Caltech/Penn State — Click on the image above to see an animation of WISE J085510.83-071442.5. It was first seen in two infrared images taken six months apart in 2010 by WISE (see orange triangles). Two additional images of the object were taken with NASA’s Spitzer Space Telescope in 2013 and 2014 (green triangles). Image credit: NASA/JPL-Caltech/Penn State

After first spotting this wacky object in the WISE data, Luhman analyzed additional images taken with the Spitzer Space Telescope and the Gemini South Pole Telescope in Chile. The combined detections taken from different positions around the Sun enabled the measurement of the objects parallax — the apparent position of the object against a background set of stars as seen along multiple lines of sight — allowing Luhman to determine the objects distance.

Spitzer’s additional observations helped pin down the objects chilly temperature, which can be determined based on how much light it gives off in different colors. Like a flame, the hottest part is blue, while the coldest part is red. Luhman found the brown dwarfs temperature to be between –54° and 9° Fahrenheit (–48° to –13° Celsius). Previous record-holders for the coldest brown dwarfs were about room temperature.

“It is remarkable that even after many decades of studying the sky, we still do not have a complete inventory of the Sun’s nearest neighbors,” said Michael Werner from NASA’s Jet Propulsion Laboratory. “This exciting new result demonstrates the power of exploring the universe using new tools, such as the infrared eyes of WISE and Spitzer.”

With a stretch of the imagination and advanced technology, it’s possible that other cooler objects, be them brown dwarfs of even rogue exoplanets, are yet closer to the Sun.

The paper will be published in the Astrophysics Journal and is available for download here.

April 29, 2014December 23, 2015 by Elizabeth Howell

How Life Could Have Produced Most Minerals On Earth

First ever image of Earth Taken by Mars Color Camera aboard India’s Mars Orbiter Mission (MOM) spacecraft while orbiting Earth and before the Trans Mars Insertion firing on Dec. 1, 2013. Image is focused on the Indian subcontinent. Credit: ISRO

While astronomers are trying to figure out which planets they find are habitable, there are a range of things to consider. How close are they to their parent star? What are their atmospheres made of? And once those answers are figured out, here’s something else to wonder about: how many minerals are on the planet’s surface?

In a talk today, the Carnegie Institution of Washington’s Robert Hazen outlined his findings showing that two-thirds of minerals on Earth could have arisen from life itself. The concept is not new — he and his team first published on that in 2008 — but his findings came before the plethora of exoplanets discovered by the Kepler space telescope.

As more information is learned about these distant worlds, it will be interesting to see if it’s possible to apply his findings — if we could detect the minerals from afar in the first place.

“We live on a planet of remarkable beauty, and when you look at it from the proximity of our moon, you see what is obviously a very dynamic planet,” Hazen told delegates at “Habitable Worlds Across Time and Space”, a spring symposium from the Space Telescope Science Institute that is being webcast this week (April 28-May 1).

His point was that planets don’t necessarily start out that way, but he said in his talk that he’d invite comments and questions on his work for alternative processes. His team believes that minerals and life co-evolved: life became more complex and the number of minerals increased over time.

Artist’s impression of a baby star still surrounded by a protoplanetary disc in which planets are forming. Credit: ESO

The first mineral in the cosmos was likely diamonds, which were formed in supernovas. These star explosions are where the heavier elements in our cosmos were created, making the universe more rich than its initial soup of hydrogen and helium.

There are in fact 10 elements that were key in the Earth’s formation, Hazen said, as well as that of other planets in our solar system (which also means that presumably these would apply to exoplanets). These were carbon, nitrogen, oxygen, magnesium, silicon, carbon, titanium, iron and nitrogen,which formed about a dozen minerals on the early Earth.

Here’s the thing, though. Today there are more than 4,900 minerals on Earth that are formed from 72 essential elements. Quite a change.

Hazen’s group proposes 10 stages of evolution:

Primary chondrite minerals (4.56 billion years ago) – what was around as the solar nebula that formed our solar system cooled. 60 mineral species at this time.
Planetesimals — or protoplanets — changed by impacts (4.56 BYA to 4.55 BYA). Here is where feldspars, micas, clays and quartz arose. 250 mineral species.
Planet formation (4.55 BYA to 3.5 BYA). On a “dry” planet like Mercury, evolution stopped at about 300 mineral species, while “wetter” planets like Mars would have seen about 420 mineral species that includes hydroxides and clays produced from processes such as volcanism and ices.
Granite formation (more than 3.5 BYA). 1,000 mineral species including beryl and tantalite.
Plate tectonics (more than 3 BYA). 1,500 mineral species. Increases produced from changes such as new types of volcanism and high-pressure metamorphic changes inside the Earth.

The official poster of the World Space Week Association 2013 campaign. Credit: World Space Week Association

These stages above are about as far as you would get on a planet without life, Hazen said. As for the remaining stages on Earth, here they are:

Anoxic biosphere (4 to 2.5 BYA), again with about 1,500 mineral species existing in the early atmosphere. Here was the rise of chemolithoautotrophs, or life that obtains energy from oxidizing inorganic compounds.
Paleoproterozoic oxidation (2.5 to 1.5 BYA) — a huge rise in mineral species to 4,500 as oxygen becomes a dominant player in the atmosphere. “We’re trying to understand if this is really true for every other planet, or if there is alternative pathways,” Hazen said.

And the final three stages up to the present day was the emergence of large oceans, a global ice age and then (in the past 540 million years or so) biomineralization or the process of living organisms producing minerals. This latter stage included the development of tree roots, which led to species such as fungi, microbes and worms.

'The Moon rising behind a couple of palm trees with cows grazing in the foreground. As you can see in the image, the bottom half of the moon has a different tint due to the earths atmosphere.' Credit: Tom Connor, Parrish, FL — ‘The Moon rising behind a couple of palm trees with cows grazing in the foreground. As you can see in the image, the bottom half of the moon has a different tint due to the earths atmosphere.’ Credit: Tom Connor, Parrish, FL

It should be noted here that oxygen does not necessarily indicate there is complex life. Fellow speaker David Catling from the University of Washington, however, noted that oxygen rose in the atmosphere about 2.4 billion years ago, coincident with the emergence of complex life.

Animals as we understand them could have been “impossible for most of Earth’s history because they couldn’t breathe,” he noted. But more study will be needed on this point. After all, we’ve only found life on one planet: Earth.

The STSCI conference continues through May 1; you can see the agenda here.

April 29, 2014December 23, 2015 by Nancy Atkinson

Astrophoto: Special Delivery to the Moon

Airbus A300 B4-622R from London to Paris -- and to the Moon? -- on April 5, 2014. Credit and copyright: Sebastien Lebrigand.

Fly me — or my package — to the Moon? “Anything is possible!” said astrophotographer Sebastien Lebrigand, via email to Universe Today. Lebrigand lives along the flight path to the Charles de Gaulle Airport in Paris and regularly takes images of planes flying in front of the Moon, (see another of his shots here), but he’s thinking this might be his best one yet.

He used a 102/660 mm refractor telescope with a Canon EOS60d camera to capture this shot.

Note: This photo does not constitute an endorsement or advertisement.

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.

April 29, 2014December 23, 2015 by David Dickinson

Amazing Images of Today’s Solar Eclipse from Earth and Space

The images are pouring in. While most of North America slept this AM, Australians were treated to the very first solar eclipse of 2014 earlier today. And while this particular eclipse was a partial one only from the Australian continent, it still offered observers a fine view of an often elusive natural spectacle.

The partial eclipse as seen from Adelaide. Credit: Michael Drew (@MichaelDrew1234)

Although rain and clouds frustrated attempts to view the eclipse from much of southern Australia, clouds parted long enough in Queensland to the east and areas around Perth to the west to offer observers a fine view. Many eclipse watchers on the Australian east coast had the additional bonus of catching the setting Sun during the eclipse.

A quick screen shot from ESA’s Proba-2 spacecraft during one of the three passes of the solar eclipse. Credit: ESA/Proba-2.

We wrote about the prospects for catching this bizarre eclipse previously. The eclipse was a rare, non-central annular with one limit only, meaning the antumbra or inner core of the Moon’s shadow just grazed the edge of the planet over Antarctica. We haven’t yet heard if anyone witnessed it from the southern polar continent, though two year round research stations were located near the path of annularity. The European Space Agency operates Concordia Station nearby as part of its Human Spaceflight Activities program and they were aware of the upcoming event. We’ll keep you updated if reports or images surface!

The eclipse seen through clouds. Photographer David Herne also noted that while he used his D3100 DSLR for the shot, his homemade pinhole camera offered fine views as well! Credit: David Herne(@AunaEridu)/Perth Western Australia.

As predicted, another solar observing sentinel in low Earth orbit did indeed witness the eclipse. ESA’s Proba-2 spacecraft caught the eclipse on three passes in this amazing raw animation from its SWAP-2 camera. The final third pass goes by extremely quick –these are measured in minutes from Proba-2’s swift vantage point – but the Sun looks well nigh to greater than 95% eclipsed by the Moon as it flies by.

The partial solar eclipse as seen from Adelaide, Australia. Credit: Silveryway.

There’s no word as of yet if the joint NASA/JAXA mission Hinode caught the eclipse as well, but we’ll keep you posted!

UPDATE: Courtesy of the European Space Agency and the Royal Observatory of Belgium, we now give you the full YouTube timelapse of the eclipse courtesy of Proba-2:

You’ll note that Proba-2 caught the partial phases on four separate passes… we also checked the sequence frame by frame, and although it looks like Proba-2 “may” have seen an annular – or even total – eclipse from space, it looks like it did so between captures!

This eclipse is one of two solar eclipses and four eclipses total for 2014. An interesting discussion occurred leading up to this eclipse as to the minimum number of eclipses that can occur in a year, which is four. If, however, you exclude faint lunar penumbrals, that number does indeed drop to two, both of which must be solar, which occurs in 2016. This also sparked a lively debate as to the naming of such a year on Twitter, with everything from a “Dwarf Eclipse Year” to “Nano Eclipse Cycle” and “Spurious Eclipse Year” being proposed. We liked the suitably esoteric and ready tweet-able term “declipsy” ourselves… thanks for the proposals and the lively discussion!

The partially-eclipsed Sun sinks into the west as seen from Brisbane, Australia on April 29, 2014. Credit and copyright: Teale Britstra.

Partial solar eclipse in Adelaide, South Australia on April 29, 2014. Credit and copyright: Silveryway on Flickr.

Thanks also to all who sent in pics. We’ll be updating this post as more come in… and although eclipse season 1 of 2 may be over for now, 2014 still has another total lunar eclipse and a good partial solar in October, both visible from North America.

…And we’re only three years out and have just two more total solar eclipses to go until the historic total solar eclipse of August 21^st, 2017…

Let the countdown begin!

UPDATE: Missed out on the solar eclipse today? Hey so did we, it happens to the best of us… luckily, YOU can now relive the all of the excitement of the eclipse courtesy of the folks from the Virtual Telescope Project in YouTube Splendor:

And finally: got pics of the partial solar eclipse that you took today and you want to share with the world? Put ’em up on Universe Today’s Flickr community and let us know!

April 28, 2014December 23, 2015 by Jason Major

Hello From Mars! Curiosity Smiles in Her Latest “Selfie”

A mosaic of MSL MAHLI images acquired on Sol 613 (NASA/JPL-Caltech/MSSS. Edit by Jason Major.)

This is very cute — Curiosity’s latest “selfie,” a mosaic I assembled from about a dozen images acquired with the rover’s Mars Hand Lens Imager (MAHLI) instrument on April 27-28, 2014 (Sol 613), with the 5.5-km-high Mount Sharp (Aeolis Mons) rising in the background. Click the image for a high-res version.

While it’s far from a perfect image — there are plenty of discrepancies in the mosaic tiling, I admit — I really like the character it imparts to Curiosity, who almost seems to be giving a toothy (if slightly dusty) grin there on the left with her cylindrical RUHF antenna and a bit of her RTG visible in the lower center. And with almost 21 Earth-months on Mars and lots of discoveries already under her robot belt, Curiosity (and her team) certainly have plenty to smile about!

See these and all the raw images from the MSL mission here, and read more about Curiosity’s latest work in Gale Crater in Ken Kremer’s article here.

April 28, 2014December 23, 2015 by Nancy Atkinson

Celebrate Hubble’s 24th Birthday by Flying Through the Pillars and Peaks of the Monkey Head Nebula

With the Hubble Space Telescope on board, Discovery begins its roll maneuver after liftoff from Kennedy Space Center on April 24, 1990. Credit: NASA.

The Hubble Space Telescope was launched 24 years ago last week, and this newly released video is a birthday present of sorts — to us!

Here you can fly into the Monkey Head Nebula (also known as NGC 2174), and this video showcases both visible and infrared light views of a collection of pillars along one edge of the nebula. The sequence begins with a view of the night sky near the constellation of Gemini and Orion, then zooms through a region of of pillars and peaks of dust.

Then comes a cross-fade transitions between Hubble’s visible and infrared light views, and it also takes you from a two-dimensional image to a three-dimensional sculpted model of the region. The camera then pulls back to reveal the landscape of evaporating peaks of gas and dust surrounded by stars.

The folks at the HubbleSite say that this visualization is intended to be a reasonable interpretation (not scientifically accurate) and that distances within the model are significantly compressed.

April 28, 2014December 23, 2015 by Elizabeth Howell

What Steps Are Needed To Find More Earths?

Artist's rendering of Kepler-186f (Credit: NASA Ames/SETI Institute/Caltech)

It wasn’t so long ago that we found out there is an Earth-sized planet in a habitable zone of a star. But how many others are out there, and do we know if planets like this are truly habitable?

“Looking towards the future, what we really want to do eventually is transform our knowledge from planets in the habitable zone to [characterizing] planetary environments,” said Natalie Batalha, a co-investigator on NASA’s Kepler Space Telescope, in a webcast presentation today (April 28) .

This means that astronomers will be able to, from a distance, look at “biosignatures” of life in the atmosphere. What a biosignature would be is still being characterized, but it could be something like an unusually high proportion of oxygen — as long as abiotic processes are not accounted for, of course.

Batalha identified these parameters for finding other Earths in a presentation at the “Habitable Worlds Across Time and Space” conference presented by the Space Telescope Science Institute:

Detections of planets: other telescopes (left) vs. Kepler. Credit: Natalie Batalha / NASA (screenshot) — Detections of planets in the habitable zone: other telescopes (left) vs. the Kepler space telescope. Credit: Natalie Batalha / NASA (screenshot)

– The telescope must be sensitive to an Earth-sized planet in the habitable zone of a G, K or M-type star (which are stars that are like the sun);

– A uniform and reliable detection catalog with well-understood sizes, orbital periods and insolation fluxes (energy received from the sun);

– Knowledge of Kepler’s detection efficiency and the planetary catalog’s reliability;

– Well-documented and accessible data products for other community members to analyze.

What would also be helpful to planetary scientists is learning more about how a planet forms in the habitable region of its star.

Meet Kepler-22b, an exoplanet with an Earth-like radius in the habitable zone of its host star. Unfortunately its mass remains unknown. Image Credit: NASA

In a presentation at the same conference, the University of Toronto’s Diana Valencia (an astrophysicist) pointed out there is no single predictor for how large a planet will get. It depends on how close a planetesimal disc is to its star, the rate of accretion in the area and dust opacity, among other factors.

She also gave a brief overview of processes that demonstrate how hard it is to predict habitability. Earth had at least two atmospheres in its past, presentation slides said, with the first atmosphere lost and the second built from volcanism and impacts. Valencia also pointed to complexities involving the Earth’s mantle and plate tectonics.

The University of Puerto Rico keeps a list of potentially habitable planets on its website, which as of this writing stands at 21.

The conference runs through May 1, and you can see the agenda here.

April 28, 2014December 29, 2015 by Susie Murph

Carnival of Space #351

Carnival of Space. Image by Jason Major.

Welcome, come in to the 351st Carnival of Space! The carnival is a community of space science and astronomy writers and bloggers, who submit their best work each week for your benefit. I’m Susie Murph, part of the team at Universe Today and now, on to this week’s stories!

Leading off the big news this week, CosmoQuest kicked off a 36-day fundraiser with a 36-hour Hangoutathon this weekend! You can go over there to find links to the schedule and the videos on YouTube, and you can still donate to help DO SCIENCE!

And if you’re wondering about what kind of science they do, in the first of what will be a series, Nicole Gugliucci explains the first peer-reviewed science paper to come from CosmoQuest citizen science. Why do we count craters, anyway?

Another worthy organization is discussed in Jason Major’s article over at Universe Today. A penny for NASA… this is the goal of Penny4NASA.org, an outreach group that strives to increase the funding — if just by a little — of the world’s most accomplished, inspirational, and powerful space exploration administration. (Before… you know, it isn’t.)

Then we go over to Brian Wang’s Next Big Future blog, where he give us the scoop on the SpaceX Falcon 9 rocket booster’s successful return to Earth, where it deployed its landing legs, and hovered for a moment. The ability, known as a soft landing, could allow the company to dramatically reduce the cost of spaceflight and one day land rockets on Mars. Then Brian covers SpaceX’s intentions to use the Spacex Heavy lift vehicle and the Spiderfab robotic assembly machine to create structures in orbit cheaper and easier, such as space-based mirror farms to collect solar energy.

Next, we go over to Vega00.com where, until now, the orbital stability of the two nearest planets to 55 Cancri has been a mystery. Now, a new computational simulation shows that this is possible. (This article is written in Spanish.)

Then, Zain Husain over at BrownSpaceMan.com explains What are white holes? It’s just a theory for now and possibly all it will ever be however, why is that? Here we take a look at the definition of a white hole and what we understand about them.

Next, over at the Chandra X-Ray Observatory blog, they explain how professional and amateur astronomers can join forces to
study the skies, since amateurs have one resource that professionals often lack – time to focus on one research project in depth.

An example of how an amateur observer’s patience and persistence paid off with a valuable scientific discovery is the story at Simstronomy. Rod Stubbings discovered OQ Carinae: A New Southern Z Cam Type Dwarf Nova, simply by putting in the time and effort to observe and record details for 14 years on a garden-variety dwarf nova. Congratulations to Rod, and we look forward to more observations and discoveries from you!

So how do we get amateurs interested in astronomy? Pam Hoffman and Jeff Miller over at EverydaySpacer have an ongoing discussion the new version of Cosmos, hosted by Neil Degrasse Tyson, and how it may influence a new generation of scientists and astronomy buffs. This week, Pamela points out some issues regarding religion and a significant sticking point with her – the lack of mention of significant influences women have had in the history of science. I agree, Pamela – they’ve had a great opportunity, since they’re focusing on lesser known stories. Hopefully they’ll mention some important contributions that women have made in the remainder of the episodes!

Then we go over to Doc Madhattan for some great exercises that can be done in the classroom for the next generation of scientists. This week, simulate the transits of exoplanets, to explain how we’re discovering such far-away objects!

And finally, keep your eyes on the skies – we’re about to be treated to Comet PANSTARRS K1 as it swings by the Big Dipper this week, and sprouts a second tail! Read more over at Universe Today!

That’s it for this week’s Carnival – it was a good week in space and science news! See you all next time!

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.

April 28, 2014December 23, 2015 by Bob King

May Meteor Storm Alert: All Eyes on the Sky!

Composite photo of Lyrid meteor shower and non-Lyrids taken with a NASA All-sky camera April 21-23, 2012. Credit: NASA/MSFC/Danielle Moser

On Friday night/early Saturday May 23-24 skywatchers across the U.S. and southern Canada may witness the birth of a brand new meteor shower. If predictions hold true, Earth will pass through multiple tendrils of dust and pebbly bits left behind by comet 209P/LINEAR, firing up a celestial display on par with the strongest showers of the year. Or better.

Peter Jenniskens of the SETI Institute, who predicted a possible meteor storm associated with comet 209P/LINEAR. Credit: NASA

Earlier predictions called for a zenithal hourly rate or ZHR of 1,000 per hour, pushing this shower into the ‘storm’ category. ZHR is an idealized number based on the shower radiant located at the zenith under ideal skies. The actual number is lower depending on how far the radiant is removed from the zenith and how much light pollution or moonlight is present. Meteor expert Peter Jenniskens of the SETI Institute and Finland’s Esko Lyytinen first saw the possibility of a comet-spawned meteor storm and presented their results in Jenniskens’ 2006 book Meteor Showers and Their Parent Comets.

Approximate location of the radiant of the 209P/LINEAR shower at the peak of the brief maximum around 2 a.m. CDT May 24. Between 100-400 meteors may radiate from the dim constellation of Camelopardalis near the North Star. This map shows the sky from Des Moines, Iowa. Created with Stellarium — Approximate location of the radiant (blue) of the 209P/LINEAR shower at the peak of the brief maximum around 2 a.m. CDT May 24. Between 100-400 meteors may radiate from the dim constellation of Camelopardalis near the North Star. This map shows the sky from the central U.S. Created with Stellarium

Quanzhi Ye and Paul Wiegert (University of Western Ontario) predict a weaker shower because of a decline in the comet’s dust production rate based on observations made during its last return in 2009. They estimate a rate of ~200 per hour.

On the bright side, their simulations show that the comet sheds larger particles than usual, which could mean a shower rich in fireballs. Other researchers predict rates between 200 and 40o per hour. At the very least, the Camelopardalids – the constellation from which the meteors will appear to originate – promise to rival the Perseids and Geminids, the year’s richest showers. Motivation for setting the alarm clock if there ever was.

Comet 209P/LINEAR on April 14, 2014. It’s currently very faint at around magnitude 17. Material shed by the comet during passes between 1898-1919 may spawn a rich meteor shower overnight May 23-24. Credit: Ernesto Guido, Nick Howes, Martino Nicolini — Comet 209P/LINEAR on April 14, 2014. It’s currently very faint at around magnitude +17. Material shed by the comet during passes from 1898-1919 is expected to contribute to a May 23-24 shower. Credit: Ernesto Guido, Nick Howes, Martino Nicolini

Comet 209P/LINEAR, discovered in Feb. 2004 by the automated Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) sky survey, orbits the sun every 5.04 years with an aphelion (most distant point from the sun) near Jupiter. In 2012, during a relatively close pass of that planet, Jupiter perturbed its orbit, bringing it to within 280,000 miles (450,000 km) of Earth’s orbit.

That set up a remarkably close encounter with our planet on May 29 when 209P will cruise just 5 million miles (8 million km) from Earth to become the 9th closest comet ever observed. Multiple debris trails shed by the comet as long ago as the 18th century will intersect our planet’s path 5 days earlier, providing the material for the upcoming meteor shower/storm.

Shining meekly around magnitude +17 at the moment, 209P/LINEAR could brighten to magnitude +11 as it speeds from the Big Dipper south to Hydra during the latter half of May. Closer to the BIG night, we’ll provide helpful maps for you to track it down in your telescope. Cool to think that both the shower and its parent comet will be on display at the same time.

The shaded area shows where the shower will be visible on May 23-24. North of the red line, the moon (a thick crescent) will be up during shower maximum around 2:10 a.m. CDT. Credit: Mikhail Maslov

The shower’s expected to last only a few hours from about 12:40-3:50 a.m. CDT with the best viewing locations in the U.S. and southern half of Canada. This is where the radiant will be up in a dark sky at peak activity. A thick crescent moon rises around 3-3:30 a.m. but shouldn’t pose a glare problem.

Meteors from 209P/LINEAR are expected to be bright and slow with speeds around 40,000 mph compared to an average of 130,000 mph for the Perseids. Most shower meteoroids are minute specks of rock, but the Camelopardalids contain a significant number of particles larger than 1mm – big enough to spark fireballs.

The dark streak is a series of filaments of dust and grit left behind by 209P/LINEAR mostly between 1803 and 1924 that Earth (shown on path) will pass through on May 23-24, 2014. Credit: — The dark “finger” represents streams of dust and rocks left behind by 209P/LINEAR during passes made from 1803 to 1924. Earth is shown intersecting the debris on May 23-24, 2014. Credit: Dr. Jeremie Vaubaillon

The farther north you live in the shaded area on the map, the higher the radiant stands in the northern sky and the more meteors you’re likely to see. Skywatchers living in the Deep South will see fewer shooting stars, but a greater proportion will be earthgrazers, those special meteors that skim the upper atmosphere and flare for an unusually long time before fading out.

To see the shower at its best, find a dark place with an open view to the north. Plan your viewing between 12:30 and 4 a.m. CDT (May 24), keeping the 2 a.m. forecast peak in mind. Maximum activity occurs around 3 a.m. Eastern, 1 a.m. Mountain and midnight Pacific time.

No one’s really certain how many meteors will show, but I encourage you to make the effort to see what could be a spectacular show.

April 28, 2014March 8, 2017 by Fraser Cain

Where Is the Center of the Universe?

In a previous episode we hinted that every spot is at the center of the Universe. But why? It turns out, every way you look at it, you’re standing dead center at the middle of everything. And so is everyone else.

We ended a previous episode with how the center of the Universe is everywhere, and then quickly moved on to “Thanks for watching” without providing any details other than a wink and a nod.

Good news, here come your details. First, imagine the expanding Universe in your mind. You might be picturing an inflating ball pushing out in all directions. Perhaps you’re seeing some kind of giant expanding celestial pumpkin. Unfortunately, that idea is incorrect. But don’t feel bad, our thinking meat parts just aren’t built to do this sort of thing.

The region of space that we can see is the observable Universe. When we look in any direction, we’re seeing the light that left stars millions and even billions of years ago. When you get out to the 13.8 billion light year mile marker, you’re seeing the light that was emitted shortly after the Big Bang, when the Universe cooled down to the point that it became transparent. So the observable Universe is a sphere around you, it’s relative to your position.

My observable Universe is a sphere around me, relative to my position. So if I’m 10 meters away from you, I can see a little further into the Universe in that direction. If you look behind you, you’re seeing the observable Universe a little further in the that direction.

Imagine you’re standing in a dark room holding a candle. You can see out into a sphere around you. You’re at the center of your observable space. And if I’m in a different location, I’ll have a different observable sphere. This is why we say that everyone is at the center of their own personal observable Universe.

This has hints of pedantry and it’s a little unsatisfying, so let’s dig a little deeper. Where is the actual center of the Universe, regardless of who’s observing it? Our Universe might be finite or it might be infinite. Astronomers don’t actually know for sure. Their most precise calculations say that the observable Universe is 93 billion light years across.

Representation of the timeline of the universe over 13.7 billion years, and the expansion in the universe that followed. Credit: NASA/WMAP Science Team.

Remember that light from the Big Bang that took 13.8 billion light years to get to you? Well the expansion of the Universe has pushed that region out to more than 46 billion light-years away. Look as far as you can to the right and as far as you can to the left. Those two spots are currently 93 billion light-years away from each other. So we can’t see how big the Universe really is. It’s got to be larger than 93 billion light-years. Everything outside that region we just can’t see… yet. It might be infinite.

If the Universe is infinite, then there’s an infinite amount of space in that direction and an infinite amount of space in that direction, and that direction. And we’re back where we started, literally. Once again, you’re at the center of the Universe. And so am I.

But what if the Universe is finite? That’s where it gets tricky. Imagine the observable Universe as a tiny sphere inside the much larger actual Universe. Maybe it’s 100 billion light years across, or maybe a trillion, or a quadrillion. Whatever the size, it’s not infinite. Now you would think there’s a center, right?

Well, astronomers think that the topology of a finite Universe indicates that if you travel in any one direction long enough, you’ll return to your starting point. In other words, if you could look far enough in any direction, you’d see the back of your head.

Imagine the universe as a sphere - Advanced Celestial Sphere (Wolfram Project). Credit: Jim Arlow — Imagine the universe as a sphere – Advanced Celestial Sphere (Wolfram Project). Credit: Jim Arlow

We did a whole episode on this, and you might want to check it out. And you’ll really want to check out Zogg the Aliens’ in-depth explanation. As an analogy, consider an ant on the surface of a sphere. Should the ant choose to walk in any direction, it’ll return to its starting point. Take that concept and scale it up one dimension. Can’t imagine it? No problem. Like I said, our brains aren’t equipped or experienced. And yet, that extra dimension seems to be the nature of the Universe. Regardless of what direction you travel, if it takes you the same amount of time to return to your starting point. Well… you’re at the center of the Universe?

See? No matter how you think about it and break it down, you’re at the center of everything. And so am I. What do you think? Is the Universe finite or infinite? Tell us why in the comments below.