Universe Today

April 3, 2013December 23, 2015 by Nancy Atkinson

Astrophotos: We Have Liftoff from the Sun!

A large prominence from the Sun, on April 1, 2013. Credit and copyright: Paul Andrew.

Here are three images showing large prominences recently lifting off from the Sun’s surface. Solar prominences are sheets or arcs of luminous gas emanating from the Sun’s surface. They can loop hundreds of thousands of kilometers into space. In the image below by noted Australian amatuer Monty Leventhal, he estimates the prominence he captured stretches 233,000 km! Against the Sun, prominences appear dark, but against the sky they appear brighter. Prominences are held above the Sun’s surface by strong magnetic fields and can sometimes last for long periods of time.

See more and varied views below:

A negative image of the Sun and large prominences on March 31, 2013. Credit and copyright: César Cantú.

This digital filtergram shows an active prominence on the SE limb of the Sun, stretching across for approximately 233,000 km on March 27, 2013. Credit and copyright: Monty Leventhal.

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 3, 2013December 23, 2015 by Jason Major

How Big Are Galaxies?

Galaxy size comparison chart by astrophysicist Rhys Taylor

I’m going to refrain from the initial response that comes to mind… actually, no I won’t — they’re really, really, really big!!!!

</Kermit arms>

Ok, now that that’s out of the way check out this graphic by Arecibo astrophysicist Rhys Taylor, which neatly illustrates the relative sizes of 25 selected galaxies using images made from NASA and ESA observation missions… including a rendering of our own surprisingly mundane Milky Way at the center for comparison. (Warning: this chart may adversely affect any feelings of bigness you may have once held dear.) According to Taylor on his personal blog, Physicists of the Caribbean (because he ~~works~~ had worked at the Arecibo Observatory in Puerto Rico) “Type in ‘asteroid sizes’ into Google and you’ll quickly find a bunch of images comparing various asteroids, putting them all next to each at the same scale. The same goes for planets and stars. Yet the results for galaxies are useless. Not only do you not get any size comparisons, but scroll down even just a page and you get images of smartphones, for crying out loud.” So to remedy that marked dearth of galactic comparisons, Taylor made his own. Which, if you share my personal aesthetics, you’ll agree is quite nicely done.

“I tried to get a nice selection of well-known, interesting objects,” Taylor explains. “I was also a little limited in that I needed high-resolution images which completely mapped the full extent of each object… still, I think the final selection has a decent mix, and I reckon it was a productive use of a Saturday.” And even with the dramatic comparisons above, Taylor wasn’t able to accurately portray to scale one of the biggest — if not the biggest — galaxies in the observable universe: IC 1101.

For an idea of how we measure up to that behemoth, he made this graphic:

Galaxy sizes including IC 1101, the largest-known galaxy. Click for a zoomable version. (Credit: Rhys Taylor)

That big bright blur in the center? That’s IC 1101, the largest known galaxy — in this instance created by scaling up an image of M87, another supersized elliptical galaxy that just happens to be considerably closer to our own (and thus has had clearer images taken of it.) But the size is right — IC 1101 is gargantuan.

At an estimated 5.5 million light-years wide, over 50 Milky Ways could fit across it! And considering it takes our Solar System about 225 million years to complete a single revolution around the Milky Way… well… yeah. Galaxies are big. Really, really, really, really big!

</Kermit arms>

Now if you’ll pardon me, I need to go stop my head from spinning… Read this and more on Rhys Taylor’s blog here, and add Rhys to your awesome astronomy Google+ circles here. And you can find out more about IC 1101 in the video below from Tony Darnell, aka DeepAstronomy:

April 3, 2013December 23, 2015 by Nancy Atkinson

Earth Month: NASA Launches New Interactive Image Gallery

Ice sheet loss increasing at both poles. Image credit: Ian Joughin, University of Washington.

In honor of Earth month, NASA has launched a beautiful new interactive image gallery that explores and highlights our latest understanding of Earth science and our changing planet. Included are spectacular images and visualizations to help understand the latest findings.

Included is information on the decline of sea ice in the Arctic, a visualization of global aerosols, images of the latest storms, and much more.

Check out the “Earth Month 2013” website.

April 3, 2013December 23, 2015 by Nancy Atkinson

First-Ever High Resolution Radio Images of Supernova 1987A

An overlay of radio emission (contours) and a Hubble space telescope image of Supernova 1987A. Credit: ICRAR (radio contours) and Hubble (image.)

On February 23, 1987, the brightest extragalactic supernova in history was seen from Earth. Now 26 years later, astronomers have taken the highest resolution radio images ever of the expanding supernova remnant at extremely precise millimeter wavelengths. Using the Australia Telescope Compact Array radio telescope in New South Wales, Australia, Supernova 1987A has been now observed in unprecedented detail. The new data provide some unique imagery that takes a look at the different regions of the supernova remnant.

“Not only have we been able to analyze the morphology of Supernova 1987A through our high resolution imaging, we have compared it to X-ray and optical data in order to model its likely history,” said Bryan Gaensler, Director of CAASTRO (Centre for All-sky Astrophysics) at the University of Sydney.

Radio image at 7 mm. Credit: ICRAR Radio image of the remnant of SN 1987A produced from observations performed with the Australia Telescope Compact Array (ATCA). — Radio image at 7 mm. Credit: ICRAR
Radio image of the remnant of SN 1987A produced from observations performed with the Australia Telescope Compact Array (ATCA).

SN 1987A has been on one of the most-studied astronomical objects, as its “close” proximity in the Large Magellanic Cloud allows it to be a focus for researchers around the world. Astronomers says it has provided a wealth of information about one of the Universe’s most extreme events.

“Imaging distant astronomical objects like this at wavelengths less than 1 centimetre demands the most stable atmospheric conditions,” said lead author, Giovanna Zanardo of ICRAR, the International Center for Radio Astronomy Research. “For this telescope these are usually only possible during cooler winter conditions but even then, the humidity and low elevation of the site makes things very challenging,”

Unlike optical telescopes, a radio telescope can operate in the daytime and can peer through gas and dust allowing astronomers to see the inner workings of objects like supernova remnants, radio galaxies and black holes.

“Supernova remnants are like natural particle accelerators, the radio emission we observe comes from electrons spiraling along the magnetic field lines and emitting photons every time they turn. The higher the resolution of the images the more we can learn about the structure of this object,” said Professor Lister Staveley-Smith, Deputy Director of ICRAR and CAASTRO.

An RGB overlay of the supernova remnant. Credit: ICRAR A Red/Green/Blue overlay of optical, X-Ray and radio observations made by 3 different telescopes. In red are the 7-mm (44GHz) observations made with the Australian Compact Array in New South Wales, in green are the optical observations made by the Hubble Space Telescope, and in blue is an X-ray view of the remnant, observed by Nasa's space based Chandra X-ray Observatory. — An RGB overlay of the supernova remnant. Credit: ICRAR
A Red/Green/Blue overlay of optical, X-Ray and radio observations made by 3 different telescopes. In red are the 7-mm (44GHz) observations made with the Australian Compact Array in New South Wales, in green are the optical observations made by the Hubble Space Telescope, and in blue is an X-ray view of the remnant, observed by Nasa’s space based Chandra X-ray Observatory.

Scientists study the evolution of supernovae into supernova remnants to gain an insight into the dynamics of these massive explosions and the interaction of the blast wave with the surrounding medium.

The team suspects a compact source or pulsar wind nebula to be sitting in the centre of the radio emission, implying that the supernova explosion did not make the star collapse into a black hole. They will now attempt to observe further into the core and see what’s there.

Their paper was published in the Astrophysical Journal.

Source: ICRAR

April 2, 2013December 23, 2015 by Jason Major

NASA Trailer Achieves Crowdfunding Goal to Run Before Star Trek: Into Darkness

Here’s one bit of NASA outreach that won’t be affected by suspensions or sequesters: an edited version of “We Are The Explorers,” a video highlighting the past successes and future goals of the space administration — created by NASA and featuring an inspiring narration by Peter “Optimus Prime” Cullen — will be screened in several major U.S. cities during the premiere of Star Trek Into Darkness thanks to an overwhelmingly successful crowdfunding effort on Indiegogo.com.

Now that the initial goal of $33,000 has been met and the 30-second ad spot can be purchased, the team responsible for the campaign (Aerospace Industries Association of America) will use any funds donated during the next 29 days to reach its next target: getting the ad in at least one theater in every state in America for two weeks. In order for that to happen, a grand total of $94,000 will need to be reached.

Want to help make it so? Find out more about how you can contribute:

According to the Indiegogo campaign page, “If we raise our funding total to $94,000, students, young people, and the general public will see this video from coast to coast. This new goal will expand our reach from 59 movie theater screens to 750 screens!”

That means a lot more chances that the spot will run at the theater where you go to see the new Star Trek film when it comes out on May 17. (Because you know you’re going to go see it, let’s be honest. It’s Star Trek.)

And because it’s Indiegogo you’ll get a “perk” depending on the amount you contribute, ranging from digital copies of the final spot to DVD copies of the excellent HBO series “From Earth to the Moon” (while supplies last.) Because the initial goal has been met, some perks are already sold out… but then, contributing to something as important as space exploration isn’t about the stuff you get, it’s about the message you can give.

“This is more than a fundraiser, it’s a demonstration of support for space exploration programs. By donating to this campaign, you’re making a very powerful statement about the widespread enthusiam that exists for space programs. A crowdfunding campaign is the best vehicle to deliver this message. By reaching our goal, we not only enable a first-of-its-kind ad campaign, we also demonstrate that countless people support a strong space program that’s in development.”

You can contribute here, and be sure to spread the word too. That way, when you’re looking at the video on the big screen, when you see them putting Al Shepard’s gloves on, when you see the fiery exhaust of the Saturn rocket and you hear Cullen’s voice rumble “we are the explorers,” you can know that you helped make it happen — and that somewhere in that same theater a young mind may very well be inspired to continue the exploration.

Maybe that mind might even be be your own.

“Our next destination awaits. We don’t know what new discoveries lie ahead, but this is the very reason we must go.“

This crowdfunding campaign is the work of the Aerospace Industries Association (AIA) of America. This campaign is not endorsed by NASA nor is it conducted at their direction or request. Note: by donating you acknowledge that donations are not tax deductible.

April 2, 2013December 23, 2015 by Nancy Atkinson

Astronomers Watch as a Black Hole Eats a Rogue Planet

In Star Wars, the Millennium Falcon narrowly escaped being devoured by an exogorth (space slug) slumbering inside an asteroid crater. An unsuspecting rogue giant planet wasn’t as lucky. Astronomers using the Integral space observatory were able to watch as the planet was eaten by a black hole that had been inactive for decades. It woke up just in time to make a meal out of the unwary planet.

“The observation was completely unexpected, from a galaxy that has been quiet for at least 20–30 years,” says Marek Nikolajuk of the University of Bialystok, Poland, lead author of the paper in Astronomy & Astrophysics.

Nikolajuk and his team added that the event is a preview of a similar feeding event that is expected to take place with the black hole at the center of our own Milky Way Galaxy.

The discovery in galaxy NGC 4845, 47 million light-years away, was made by Integral, with follow-up observations from ESA’s XMM-Newton, NASA’s Swift and Japan’s MAXI X-ray monitor on the International Space Station.

Astronomers were using Integral to study a different galaxy when they noticed a bright X-ray flare coming from another location in the same wide field-of-view. Using XMM-Newton, the origin was confirmed as NGC 4845, a galaxy never before detected at high energies.

Along with Swift and MAXI, the emission was traced from its maximum in January 2011, when the galaxy brightened by a factor of a thousand, and then as it subsided over the course of the year.

By analyzing the characteristics of the flare, the astronomers could determine that the emission came from a halo of material around the galaxy’s central black hole as it tore apart and fed on an object of 14–30 Jupiter masses, and so the astronomers say the object was either a super-Jupiter or a brown dwarf.

This object appears to have been ‘wandering,’ which would fit the description of recent studies that have suggested that free-floating planetary-mass objects of this kind may occur in large numbers in galaxies, ejected from their parent solar systems by gravitational interactions.

The black hole in the center of NGC 4845 is estimated to have a mass of around 300,000 times that of our own Sun. The astronomers said it also appears to enjoy playing with its food: the way the emission brightened and decayed shows there was a delay of 2–3 months between the object being disrupted and the heating of the debris in the vicinity of the black hole.

“This is the first time where we have seen the disruption of a substellar object by a black hole,” said co-author Roland Walter of the Observatory of Geneva, Switzerland. “We estimate that only its external layers were eaten by the black hole, amounting to about 10% of the object’s total mass, and that a denser core has been left orbiting the black hole.”

The flaring event in NGC 4845 might be similar to what is expected to happen with the supermassive black hole at the center of our own Milky Way Galaxy, perhaps even this year, when an approaching Earth-mass gas cloud is expected to meet its demise.

Along with the object seen being eaten by the black hole in NGC 4845, these events will tell astronomers more about what happens to the demise of different types of objects as they encounter black holes of varying sizes.

“Estimates are that events like these may be detectable every few years in galaxies around us, and if we spot them, Integral, along with other high-energy space observatories, will be able to watch them play out just as it did with NGC 4845,” said Christoph Winkler, ESA’s Integral project scientist.

The team’s paper: Tidal disruption of a super-Jupiter in NGC 4845

Source: ESA

April 2, 2013December 30, 2015 by Nancy Atkinson

Night Sky Preview for April 2013

Here’s a quick overview from Jane Houston Jones from JPL of what you can see in the night skies during April 2013. Of special interest is that Saturn’s north pole is now tilted towards Earth, giving us the best view of the rings since 2006.

April 2, 2013December 23, 2015 by Elizabeth Howell

The Man Who Sold The Moon … And Other ‘Lunarcy’

One man claims to own the moon. Another promises to create effective lunar habitats. And yet another, a former astronaut, paints pictures of its surface.

Lunarcy! is a movie that chronicles our obsession with the Moon. It’s currently making the rounds at independent theatres, but before long it will be easy to watch it on cable, or even Netflix and Amazon.

The film chronicles the efforts of half a dozen people working, in their own way, to bring the notion of regular Moon exploration closer to reality. There’s Alan Bean, the Apollo 12 moonwalker who now paints scenes of lunar exploration. Or Dennis Hope, who has staked a claim on the entire Moon and has sold plots to interested homesteaders.

At the story’s center, however, is an ordinary man called Christopher Carson who is convinced he could be the first person to colonize the Moon — if he could only obtain enough money. Director Simon Ennis follows his efforts to get funds and awareness, sprinkling the rest of the movie with other lunar-loving people.

Universe Today caught up with Ennis, who answered our questions by e-mail.

1) What was your aim with filming/presenting Lunarcy?

As with any film, the aim is to make something that is entertaining, informative and moving. Something that can capture people’s imagination in some way.

2) Why is the moon so attractive to the people in you interviewed?

They all had different reasons. Some want to live there, some are inspired by it, for Dennis Hope (the man who owns it), he saw a business opportunity. Others are interested in space exploration in general and the Moon seems the most practical first step. Apollo astronaut Alan Bean has been there, so his attraction should be obvious.

3) One of your greatest challenges must have been trying to present some of the characters — people such as Christopher Carson, who has been ignored in his belief that living on the moon is possible — in a way that helps the audience feel understanding for their cause. How did you try to do that?

I don’t think that was much of a challenge actually. I only included subjects in the film who I felt a very strong affinity for, whose goals, quests or projects were ones that caught my imagination and that I could get behind myself. Considering that I felt understanding for the “cause”, I figured that would naturally come through to the audience.

4) A minor theme in Lunarcy! is presenting the moon as a viable place to do business — selling plots of land or colonizing it, for example. We also have companies that are looking to mine asteroids. But often, these plans meet with ridicule, as Newt Gingrich discovered when he promised a moon base. What, in your view, will it take for off-earth private ventures such as these to succeed?

I think they will ultimately succeed when they become financially viable industries. For that to happen, I suspect that some of the billionaire space enthusiasts (e.g. [SpaceX‘s Elon] Musk, [Virgin Galactic’s Richard Branson, etc) will have to invest their own funds to get various projects going and to show that they’re not only possible but viable. So far SpaceX seems to be doing just this.

5) What else would you like to add?

Lunarcy! will premiere on EPIX on April 3 and will be available on Netflix and Amazon at the beginning of July.

April 2, 2013December 23, 2015 by Nancy Atkinson

MAVEN’s Magnetometer Will Look Back in Time

Artist depiction of the MAVEN spacecraft. Credit: NASA

The next mission to the Red Planet, the Mars Atmosphere and Volatile Evolution (MAVEN) will be the first spacecraft ever to make direct measurements of the Martian atmosphere. MAVEN will carry eight science instruments, including a magnetometer that will investigate what remains of Mars’ magnetic “shield,” and will, in essence, help to look back in time at what may have happened to a planet once thought to have an abundance of liquid water but is now a frozen desert. The magnetometer will play a key role in studying the planet’s atmosphere and interactions with solar wind, helping answer the question of why Mars lost much of its atmosphere.

“The magnetometer helps us see where the atmosphere is protected by mini-magnetospheres and where it’s open to solar wind,” said Jack Connerney, a co-investigator for the mission. “We can study the solar wind impact and how efficient it is at stripping the atmosphere.”

By measuring sections of the planet’s magnetic field, the magnetometer could help scientists create a bigger picture of the planet’s overall atmosphere.

MAVEN is the first mission to Mars specifically designed to help scientists understand the past – and also the ongoing — escape of CO2 and other gases into space. MAVEN will orbit Mars for at least one Earth-year, about a half of a Martian year. MAVEN will provide information on how and how fast atmospheric gases are being lost to space today, and infer from those detailed studies what happened in the past.

Studying how the Martian atmosphere was lost to space can reveal clues about the impact that change had on the Martian climate, geologic, and geochemical conditions over time, all of which are important in understanding whether Mars had an environment able to support life.

MAVEN is scheduled to launch in 2013, with a launch window from Nov. 18 to Dec 7, 2013. Mars Orbit Insertion will be in mid-September2014.

Find out more about MAVEN at the mission website.

April 2, 2013December 23, 2015 by Jason Major

Astronaut Photos Create a Map of the World

A map of the world made up of the locations of ISS astronaut photos (Nathan Bergey/open.nasa.gov)

If you could spend a few months — or even a few days — living aboard the ISS, what would you take pictures of? Earth, most likely, with your favorite landforms and your family’s and friends’ hometowns ranking high on the list. After a while, I’m sure plenty of other Earthly features would become photo targets — weather, aurorae, world cities at night, etc. — but ultimately, over the course of your stay in orbit, you would be able to see a trend in the pictures you take, and where you took them.

And over the span of 35 missions across more than 12 years, the graph above shows the trend of all the astronauts’ pictures. Look familiar?

Nighttime photo of the Nile delta region taken from the ISS (NASA)

Created by open-source NASA data aficionado Nate Bergey, the image above is a map made up of over a million points (1,129,177, to be exact) each representing the global coordinates of an JSC-archived photograph taken from the ISS.

Clearly the continents are astronauts’ favored photo subjects, with the populous urban areas of North America, Europe, Egypt and the Middle East, as well as the western and southern coasts of South America standing out.

“This makes sense, photos of clouds over an otherwise blank ocean get old after a while,” Nate Bergey wrote on his blog, open.nasa.gov. “I’m sure every astronaut has taken at least one photograph of the town they grew up in.”

Of course, the map doesn’t create an image of the entire globe. This is because the points denote actual over-ground coordinates of the Station (not necessarily what the photos themselves are of) and “the ISS stays between about 50° and -50° latitude as it orbits the Earth,” as noted by Bergey.

A map of the world with the points overlaid onto it, color-coded by mission, shows the difference:

Bergey also notes the proliferation of purple-colored dots… these indicate the hundreds of images taken by NASA astronaut Don Pettit during Expedition 30/31, when he created incredible time-lapse videos of the Earth from the ISS.

One of many long-exposure images taken by Don Pettit aboard the ISS (NASA/JSC). See more here.

With such a unique and lofty perspective of our world, it’s no wonder that astronauts spend so much time snapping photos — I can’t say I’d be able to tear myself away from the window myself! Read more about Nate Bergey’s project and how he created his map on his open.NASA blog here.