New Research Suggests Better Ways To Seek Out Pale Blue Dots

Artist’s impression of how an an Earth-like exoplanet might look. Credit: ESO.

The search for worlds beyond our own is one of humankind’s greatest quests. Scientists have found thousands of exoplanets orbiting other stars in the Milky Way, but are still ironing out the details of what factors truly make a planet habitable. But thanks to researchers at Cornell University, their search may become a little easier. A team at the Institute for Pale Blue Dots has zeroed in on the range of habitable orbits for very young Earth-like planets, giving astronomers a better target to aim at when searching for rocky worlds that contain liquid water and could support the evolution of life.

The Habitable Zone (HZ) of a star is its so-called “Goldilocks region,” the not-too-hot, not-too-cold belt within which liquid water could exist on orbiting rocky planets. Isolating planets in the HZ is the primary objective for scientists hoping to find evidence of life. Until now, astronomers have mainly been searching for worlds that lie in the HZ of stars that are in the prime of their lives: those that are on the Main Sequence, the cosmic growth chart for stellar evolution. According to the group at Cornell, however, scientists should also be looking at cooler, younger stars that have not yet reached such maturity.

The increased distance of the Habitable Zone from pre-main sequence stars makes it easier to spot infant Earths. Credit: Astrophysical Journal Letters.
The increased distance of the Habitable Zone from pre-main sequence stars makes it easier to spot infant Earths. Credit: Astrophysical Journal Letters.

As shown in the figure above, cool stars in classes F, G, K, and M are more luminous in their pre-Main Sequence stage than they are once they mature. Planets that circle around such bright stars tend to have more distant orbits than those that accompany dimmer stars, making transits more visible and providing a larger HZ for astronomers to probe. In addition, the researchers found that fledgling planets can spend up to 2.5 billion years in the HZ of a young M-class star, a period of time that would allow ample time for life to flourish.

But just because liquid water could exist on a planet doesn’t mean that it does. A rocky planet must first acquire water, and then retain it long enough for life to develop. The Cornell group found that a watery world could lose its aqueous environment to a runaway greenhouse effect if if forms too close to a cool parent star, even if the planet was on course to eventually stray into the star’s HZ. These seemingly habitable planets would have to receive a second supply of water later on in order to truly support life. “Our own planet gained additional water after this early runaway phase from a late, heavy bombardment of water-rich asteroids,” offered Ramses Ramirez, one author of the study. “Planets at a distance corresponding to modern Earth or Venus orbiting these cool stars could be similarly replenished later on.”

Estimations for the HZs of cool, young stars and probable amounts of water loss for exoplanets orbiting at various distances are provided in a preprint of the paper, available here. The research will be published in the January 1, 2015, issue of The Astrophysical Journal.

C/2014 Q2 Lovejoy – A Binocular Comet in Time for Christmas

Like a Christmas ornament dangling from string, Comet Lovejoy Q2 is headed north and coming into good view for northern hemisphere observers in the next two weeks. This photo was taken on November 26th. Credit: Rolando Ligustri

Hmmm. Something with a long white beard is making an appearance in northern skies this week. Could it be Santa Claus? No, a bit early for the jolly guy yet, but comet watchers will soon find a special present under the tree this season.  Get ready to unwrap Comet Lovejoy Q2, now bright enough to spot in a pair of 10×50 binoculars.

Comet Lovejoy Q2 starts out low in the southern sky below Canis Major this week but quickly zooms northward. Visibility improves with each passing night. Source: Chris Marriott's SkyMap software
Comet Lovejoy Q2 starts out low in the southern sky in Puppis this week (6° max. altitude on Dec. 9) but quickly zooms north and west with each passing night. On the night of December 28-29, the comet will pass 1/3° from the bright globular cluster M79 in Lepus. This map shows the sky and comet’s position facing south from 42° north latitude around 1:30 a.m. CST. Source: Chris Marriott’s SkyMap software

Following a rocket-like trajectory into the northern sky, this visitor from deep space is no longer reserved for southern skywatchers alone. If you live in the central U.S., Lovejoy Q2 pokes its head from Puppis in the early morning hours this week. Glowing at magnitude +7.0-7.5, it’s a faint, fuzzy cotton ball in binoculars from a dark sky and visible in telescopes as small as 3-inches (7.5 cm). With the Moon past full and phasing out of the picture, comet viewing will continue to improve in the coming nights. What fun to watch Lovejoy gradually accelerate from its present turtle-like amble to agile cheetah as it leaps from Lepus to Taurus at the rate of 3° a day later this month. Why the hurry? The comet is approaching Earth and will pass nearest our planet on January 7th at a distance of 43.6 million miles (70.2 million km). Perihelion follows some three weeks later on January 30th.

Image triplet taken by Terry Lovejoy on which he discovered the comet. The comet moves slightly counterclockwise around the larger fuzzy spot. Credit: Terry Lovejoy
Terry Lovejoy discovered the comet in this triplet of images taken on August 17th. The comet moves slightly counterclockwise around the larger fuzzy spot during the sequence. Credit: Terry Lovejoy

The new object is Australian amateur Terry Lovejoy’s 5th comet discovery. He captured images of the faint, 15th magnitude wisp on August 17th with a Celestron C-8 fitted with a CCD camera at his roll-off roof observatory in Brisbane, Australia. Comet Lovejoy Q2 has a period of about 11,500 years with an orbit steeply inclined to the plane of the Solar System (80.3°), the reason for its sharp northern climb. As December gives way to January the comet crosses from below to above the plane of the planets.

Another awesome shot of Comet Lovejoy Q2 taken on November 26, 2014. Gases in the coma fluoresce green in the Sun's ultraviolet light. Credit: Damian Peach
Another awesome shot of Comet Lovejoy Q2 taken on November 26, 2014. Gases in the coma including carbon and cyanogen fluoresce green in the Sun’s ultraviolet light. The comet’s moderately condensed coma currently measures about 8 arc minutes across or 1/4 the size of the full Moon. Credit: Damian Peach

Comet Lovejoy is expected to brighten to perhaps 5th magnitude as it approaches Earth, making it faintly visible with the naked eye from a dark sky site. Now that’s what I call a great way to start the new year!

To help you find it, use the top map to get oriented; the detailed charts (below) show stars to magnitude +8.0. Click each to enlarge and then print out a copy for use at night. Bonus! Comet Lovejoy will pass only 10 arc minutes (1/3°) south of the 8th magnitude globular cluster M79 on December 28-29 – a great opportunity for astrophotographers and observers alike. Both comet and cluster will pose side by side in the same binocular and telescopic field of view. In early January I’ll post fresh maps to help you track the comet all through next month, too.

Detailed map showing the comet tomorrow morning through December 27th in the early morning hours (CST). Stars shown to magnitude +8.0. Source: Chris Marriott's SkyMap software
Detailed map showing the comet tomorrow December 9th through December 27th in the early morning hours (CST). Stars shown to magnitude +8.0. Source: Chris Marriott’s SkyMap software
Because Comet Lovejoy rapidly moves into the evening sky by mid-late December, its position on this detailed map is shown at 10 p.m. (CST) nightly. Credit:
Because Comet Lovejoy moves rapidly into the evening sky by mid-late December, its position on this detailed map is shown for 10 p.m. (CST) nightly. Credit: Chris Marriott’s SkyMap software

Workaholic Hubble Telescope Will Eventually Burn To Death: Report

The Hubble Space Telescope viewed by the STS-125 shuttle repair crew in 2009. Credit: NASA

The Hubble Space Telescope has delivered an amazing near quarter-century of science from all over the universe. Even this year, it’s delivered results to think about: the shrinking Great Red Spot on Jupiter (see picture below), helping New Horizons hunt for flyby targets after Pluto, and enhancing our view of deep space.

But that didn’t come cheap. Four astronaut servicing missions (including one to fix a mirror that was launched with myopia) were required to keep the telescope going since 1990. Hubble has never been more scientifically productive, according to a recent NASA review, but a new article asks if Hubble is destined to die a fiery death when its orbit decays in the next eight to 10 years.

“NASA doesn’t have any official plans for upgrading the telescope, meaning its hardware will grow old and out-of-date in the coming years,” reads the article in Popular Science. “Without assistance, Hubble can’t maintain its orbit forever, and eventually Earth’s gravity will pull the telescope to a fiery death.”

That’s not to say NASA is going to abandon the cosmos — far from it. Besides NASA’s other space telescopes, the successor James Webb Space Telescope is planned to launch in 2018 to chart the universe in other wavelengths. But a review from April warns that ceasing operations of Hubble would not be prudent until James Webb is up, running, and doing its own work productively. That’s a narrow window of time considering Hubble is expected to work well until about 2020.

The Hubble Space Telescope shows the shrinking size of Jupiter's Great Red Spot in this series of images taken between 1995 and 2014. Credit: NASA, ESA, and A. Simon (Goddard Space Flight Center)
The Hubble Space Telescope shows the shrinking size of Jupiter’s Great Red Spot in this series of images taken between 1995 and 2014. Credit: NASA, ESA, and A. Simon (Goddard Space Flight Center)

The Hubble Space Telescope senior review panel submitted a report on March that overall praised the observatory’s work, and which also talked about its potential longevity. As is, Hubble is expected to work until at least 2020, the review stated. The four science instruments are expected to be more than 85% reliable until 2021, and most “critical subsystems” should exceed 80% until that same year.

The report urges that experienced hands are kept around as the telescope degrades in the coming years, but points out that Hubble has backups that should keep the observatory as a whole going for a while.

There are no single-point failure modes on Hubble that could take down the entire observatory. It has ample redundancy. Planned mitigations for numerous possible sub-system failures or degraded performance have been developed in advance via the project’s Life-Extension Initiatives campaign. Hubble will likely degrade gracefully, with loss or degradation of individual science instrument modes and individual sub-system components.

In NASA’s response to the Senior Review for several missions (including Hubble), the agency said that the telescope has been approved (budgetarily speaking) until 2016, when an incremental review will take place. Further in the future, things get murky.

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)
The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

The just-tested Orion spacecraft won’t be ready to take crews until the mid-2020s, and so far (according to the Popular Science article) the commercial crew program isn’t expected to include a servicing mission.

According to STS-125 astronaut Michael Good, who currently serves in the Commercial Crew Program, the space agency isn’t looking into the possibility of using private companies to fix Hubble, but he says there’s always a chance that could happen. “One of the reasons we’re doing Commercial Crew is to enable this capability to get into lower Earth orbit,” says Good. “But it’s certainly in the realm of possibility.”

Much can happen in a decade — maybe a surge in robotic intelligence would make an automated mission more possible — but then there is the question of priorities. If NASA chooses to rescue Hubble, are there other science goals the agency would need to push aside to accomplish it? What is best? Feel free to leave your feedback in the comments.

This Drone Took Amazing Astronomical Observatory Video In Wisconsin

A drone shot of Yerkes Observatory in Chicago. Credit: Adam Novak / Vimeo (screenshot)

It’s hard to do many types of astronomy in the daylight, so that can be a good time to do a different kind of observing — enjoying the architecture of the telescope! This new video shot by a drone shows off Yerkes Observatory in snowy Williams Bay, Wisconsin. The video was uploaded by Adam Novak.

Yerkes, which is operated by the University of Chicago, calls itself the “birthplace of modern astrophysics” because it combined astronomical observations with experimentation in physics and chemistry. That’s something that’s normal in astronomy today, but certainly not in 1897.

Observations began with a 40-inch refractor (billed as the biggest such telescope ever finished) that weighs about 20 tons. While the telescope itself is from the turn of the century, the means of moving it is much more modern — from about 50 years ago, according to a National Park Service book on the observatory:

The telescope was modernized in 1969 permitting more accurate and rapid setting of the position of the telescope. The efficiency of the telescope was further increased by the addition of an automatically guiding camera. The driving clock, by which the telescope is made to follow the stars, consists of a synchronous motor controlled by an electronic oscillator, the frequency of which can he set so as to make the telescope follow the sun, the moon, or stars.

You can learn more about Yerkes on the official website.

Stretch! Moon’s Divots And Darkness Collide In Pleasing Panorama

Nine shots of the Moon overlap in this view of the terminator taken Nov. 29, 2014. Credit: Roger Hutchinson

While space explorers often set their sights far out in the Solar System — or even beyond — we can’t forget the majesty of our next-door neighbor. The Moon, a mere three days’ flight away from Earth during the Apollo years, is an easy beacon in the darkness for anybody to observe. Even without a telescope.

Lately, several Universe Today readers have contributed awesome shots to our Flickr pool showing some close-ups of this barren world. Take the panorama above by Roger Hutchinson, for example, showing the view along the terminator (darkness-light line). And we’ve collected some more stunners below.

Copernicus, a huge crater near the Moon's equator, captured on Dec. 4, 2014. Credit: Ralph Smyth
Copernicus, a huge crater near the Moon’s equator, captured on Dec. 4, 2014. Credit: Ralph Smyth
Tycho, a crater that dominates the lunar southern highlands, on Dec. 2, 2014. Credit: John Brady
Tycho, a crater that dominates the lunar southern highlands, on Dec. 2, 2014. Credit: John Brady
The Mare Nubium region on the Moon, imaged Dec. 2, 2014. Credit: Paul M. Hutchinson
The Mare Nubium region on the Moon, imaged Dec. 2, 2014. Credit: Paul M. Hutchinson
The waxing gibbous moon captured on Dec. 3, 2014 from Wednesbury, West Midlands. Credit: II AsH II
The waxing gibbous moon captured on Dec. 3, 2014 from Wednesbury, West Midlands. Credit: II AsH II

‘Cosmos’ TV Show Could Come Back For A Second Season

Dr. Neil deGrasse Tyson contemplates the Big Bang. Image courtesy of Fox.

This spring, space fans had a virtual campfire to flock to: the new Cosmos series, which aired on Fox and National Geographic for 13 science-filled episodes.

The series attracted at least three million viewers a week, generated discussions (positive and negative) on social media, brought host Neil deGrasse Tyson to even higher heights of fame, and once again, showed the general public how neat space is.

Well, guess what. According to producer Seth MacFarlane, Cosmos could come back for a second run — which would supercede the predecessor series from the 1980s, narrated by Carl Sagan!

“Early, preliminary discussions for a 2nd season of #Cosmos– If you want to see more of the great @neiltyson, tweet him your love!” MacFarlane wrote on Twitter yesterday (Dec. 3).

His comments follow a posting on Reddit that surfaced in a couple of news reports yesterday, one from a reported viewer of a deGrasse Tyson talk in New York City:

“I just attended a presentation by Tyson at NJPAC in Newark, NJ,” the posting read. “During the Q&A portion, he told the audience that he’s meeting with producers tomorrow in NYC to discuss the next “season” (for lack of better term) of COSMOS. He didn’t go into further detail, but thought this was interesting since up until this point the updated show was just considered a one-off series (ie 13 episodes).”

We’ll keep you posted as more news arises.

Giordano Bruno in Cosmos. Image courtesy of Fox.
Giordano Bruno in Cosmos. Image courtesy of Fox.

 

Yes, You Can Find Exoplanets With A Simple Camera And Telephoto Lens

Artist’s impression of the deep blue planet HD 189733b, based on observations from the Hubble Space Telescope. Credit: NASA/ESA.

If you think exoplanet detections are only in the realm of professional planet-hunting telescopes such as Kepler, take a look at the video above. David Schneider, a senior editor for IEEE Spectrum, explains that it takes little more than a DSLR camera and a camera lens to catch a glimpse.

Schneider told Universe Today that he’s not an experienced amateur observer, nor should his equipment be expected to detect new exoplanets. But the potential for the future is interesting, he explained.

“I was simply trying to detect the signature of a known exoplanet, one that was discovered years ago with far more sophisticated gear,” he wrote in an e-mail. “I knew exactly which star to look at, when the transit occurs, and what the change in brightness would be. I relied on the expertise of professional astronomers to provide all that information.”

Here’s the setup: a Canon EOS Rebel XS DSLR, a 300-millimeter Nikon telephoto lens, an adapter to get the Nikon talking to the Canon, and a self-built “barn door tracker” that he constructed based on descriptions he found on the web. (His IEEE Spectrum article has more details.)

Schneider chose HD 189733, whose hostile-to-life “deep blue” exoplanet is about 63 light-years away and transits the face of the star every 2.2 days. But often these transits take place at inconvenient times (such as during the day, and the star is low on the horizon). He also faced several cloudy nights, meaning it was several weeks until he could take the imagery.

Once that was finished, Schneider ran the pictures through a piece of astronomical imaging software called Iris. In Schneider’s words, this is how the software helped him pick out the planet:

At the most basic level, Iris allows you to perform the corrections that are customary for really all types of digital astrophotography. In particular, you correct for ‘hot pixels’ in your camera sensor and for variations in the sensitivity of the sensor across the frame. This is standard stuff in astrophotography, requiring that you take images with the lens cap on (so-called “darks”), of a uniformly illuminated background (“flats”), and so forth.

For this project, you also need to use the tools that Iris provides to do what’s called aperture photometry. In a nutshell, you have to adjust the registration of the set of images you collect so that the stars are in the same position in each image. Then you have to set up things in Iris to do photometric measurements of a selected set of stars in one frame. After that, Iris will perform the photometry you want on the whole set of images you have in an automated fashion.

While his equipment isn’t sophisticated enough to account for “false positives” such as a sunspot going across a star — amateurs are more at the stage of confirming professional observations — Schneider pointed out there are many similar projects to his own. Among them are KELT-NORTH (which inspired his search), Evryscope, and this group at the University of Arizona.

“My project merely highlights that you can get your feet wet in this area with some really cheap hardware,” Schneider said. He recommends those that want to do similar work to his read the IEEE Spectrum article, buy the hardware required, read up on astrophotography and Iris, and not be afraid to experiment.

Schneider added he wasn’t trying to do “anything special” — many amateurs have encountered similar success — but he had a lot of fun. “Maybe because I’m a bit of a computer nerd, I found digital astrophotography to be a lot more enjoyable than actually looking through a telescope, which in the few times I’ve done that often involved a lot of squinting and unpleasant vibration.”

Orion Unveiled for Maiden Launch Today Dec. 4

NASA’s first Orion spacecraft and Delta 4 Heavy Booster unveiled at Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida prior to launch set for Dec. 4, 2014. Credit: Ken Kremer - kenkremer.com

KENNEDY SPACE CENTER, FL – The inaugural blastoff of NASA’s new Orion capsule is now just hours away.

We are counting down to NASA’s new generation of human spaceflight vehicles that starts humanity on the road to Mars.

Update: Technical issue delay 1st Orion launch. Details to follow.

“This is a big deal and its importance cannot be underestimated,” NASA Administrator Charles Bolden told the media during a briefing at the Delta pad.

NASA’s first Orion spacecraft and Delta 4 Heavy Booster unveiled at Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida prior to launch set for Dec. 4, 2014.   Credit: Ken Kremer - kenkremer.com
NASA’s first Orion spacecraft and Delta 4 Heavy Booster unveiled at Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida prior to launch set for Dec. 4, 2014. Credit: Ken Kremer – kenkremer.com

Just eight hours before the planned liftoff, the media, including myself, witnessed the rollback of the service tower to unveil Orion and its Delta IV Heavy booster rocket to the heavens where it soon soar on it first test flight.

Enjoy my photo gallery herein.

The Orion capsule is designed to carry astronauts farther into space than ever before and open a new era in human spaceflight.

Orion is slated to lift off on a United Launch Alliance Delta IV Heavy rocket on its inaugural test flight to space on the uncrewed Exploration Flight Test-1 (EFT-1) mission at 7:05 a.m. EST on December 4, 2014, from Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida.

The launch window extends for 2 hours and 39 minutes.

Continue reading “Orion Unveiled for Maiden Launch Today Dec. 4”

10 Interesting Facts About the Milky Way

Viewed from above, we can now see that our gaze takes across the Perseus Arm (toward the constellation Cygnus), parts of the Sagittarius and Scutum-Centaurus arms (toward the constellations Scutum, Sagittarius and Ophiuchus) and across the central bar. Interstellar dust obscures much of the center of the galaxy. Credit: NASA et. all with additions by the author.
Viewed from above, we can now see that our gaze takes across the Perseus Arm (toward the constellation Cygnus), parts of the Sagittarius and Scutum-Centaurus arms (toward the constellations Scutum, Sagittarius and Ophiuchus) and across the central bar. Interstellar dust obscures much of the center of the galaxy. Credit: NASA et. all with additions by the author.

The Milky Way Galaxy is an immense and very interesting place. Not only does it measure some 120,000–180,000 light-years in diameter, it is home to planet Earth, the birthplace of humanity. Our Solar System resides roughly 27,000 light-years away from the Galactic Center, on the inner edge of one of the spiral-shaped concentrations of gas and dust particles called the Orion Arm.

But within these facts about the Milky Way lie some additional tidbits of information, all of which are sure to impress and inspire. Here are ten such facts, listed in no particular order:

1. It’s Warped:

For starters, the Milky Way is a disk about 120,000 light years across with a central bulge that has a diameter of 12,000 light years (see the Guide to Space article for more information). The disk is far from perfectly flat though, as can be seen in the picture below. In fact, it is warped in shape, a fact which astronomers attribute to the our galaxy’s two neighbors -the Large and Small Magellanic clouds.

These two dwarf galaxies — which are part of our “Local Group” of galaxies and may be orbiting the Milky Way — are believed to have been pulling on the dark matter in our galaxy like in a game of galactic tug-of-war. The tugging creates a sort of oscillating frequency that pulls on the galaxy’s hydrogen gas, of which the Milky Way has lots of (for more information, check out How the Milky Way got its Warp).

The Spiral Galaxy ESO 510-13 is warped similar to our own. Credit: NASA/Hubble Heritage Team (STScI / AURA), C. Conselice (U. Wisconsin / STScI/ NASA
The warp of Spiral Galaxy ESO 510-13 is similar to that of our own. Credit: NASA/Hubble

2. It Has a Halo, but You Can’t Directly See It:

Scientists believe that 90% of our galaxy’s mass consists of dark matter, which gives it a mysterious halo. That means that all of the “luminous matter” – i.e. that which we can see with the naked eye or a telescopes – makes up less than 10% of the mass of the Milky Way. Its halo is not the conventional glowing sort we tend to think of when picturing angels or observing comets.

In this case, the halo is actually invisible, but its existence has been demonstrated by running simulations of how the Milky Way would appear without this invisible mass, and how fast the stars inside our galaxy’s disk orbit the center.

The heavier the galaxy, the faster they should be orbiting. If one were to assume that the galaxy is made up only of matter that we can see, then the rotation rate would be significantly less than what we observe. Hence, the rest of that mass must be made up of an elusive, invisible mass – aka. “dark matter” – or matter that only interacts gravitationally with “normal matter”.

To see some images of the probable distribution and density of dark matter in our galaxy, check out The Via Lactea Project.

3. It has Over 200 Billion Stars:

As galaxies go, the Milky Way is a middleweight. The largest galaxy we know of, which is designated IC 1101, has over 100 trillion stars, and other large galaxies can have as many as a trillion. Dwarf galaxies such as the aforementioned Large Magellanic Cloud have about 10 billion stars. The Milky Way has between 100-400 billion stars; but when you look up into the night sky, the most you can see from any one point on the globe is about 2,500. This number is not fixed, however, because the Milky Way is constantly losing stars through supernovae, and producing new ones all the time (about seven per year).

These images taken by the Spitzer Space Telescope show the dust and gas concentrations around a supernova. Credit: NASA/JPL-Caltech
These images taken by the Spitzer Space Telescope show dust and gas concentrations around a distant supernova. Credit: NASA/JPL-Caltech

4. It’s Really Dusty and Gassy:

Though it may not look like it to the casual observer, the Milky Way is full of dust and gas. This matter makes up a whopping 10-15% of the luminous/visible matter in our galaxy, with the remainder being the stars. Our galaxy is roughly 100,000 light years across, and we can only see about 6,000 light years into the disk in the visible spectrum. Still, when light pollution is not significant, the dusty ring of the Milky Way can be discerned in the night sky.

The thickness of the dust deflects visible light (as is explained here) but infrared light can pass through the dust, which makes infrared telescopes like the Spitzer Space Telescope extremely valuable tools in mapping and studying the galaxy. Spitzer can peer through the dust to give us extraordinarily clear views of what is going on at the heart of the galaxy and in star-forming regions.

5. It was Made From Other Galaxies:

The Milky Way wasn’t always as it is today – a beautiful, warped spiral. It became its current size and shape by eating up other galaxies, and is still doing so today. In fact, the Canis Major Dwarf Galaxy is the closest galaxy to the Milky Way because its stars are currently being added to the Milky Way’s disk. And our galaxy has consumed others in its long history, such as the Sagittarius Dwarf Galaxy.

6. Every Picture You’ve Seen of the Milky Way Isn’t It:

Currently, we can’t take a picture of the Milky Way from above. This is due to the fact that we are inside the galactic disk, about 26,000 light years from the galactic center. It would be like trying to take a picture of your own house from the inside. This means that any of the beautiful pictures you’ve ever seen of a spiral galaxy that is supposedly the Milky Way is either a picture of another spiral galaxy, or the rendering of a talented artist.

Artist's concept of Sagittarius A, the supermassive black hole at the center of our galaxy. Credit: NASA/JPL
Artist’s concept of Sagittarius A, the supermassive black hole at the center of our galaxy. Credit: NASA/JPL-Caltech

Imaging the Milky Way from above is a long, long way off. However, this doesn’t mean that we can’t take breathtaking images of the Milky Way from our vantage point!

7. There is a Black Hole at the Center:

Most larger galaxies have a supermassive black hole (SMBH) at the center, and the Milky Way is no exception. The center of our galaxy is called Sagittarius A*, a massive source of radio waves that is believed to be a black hole that measures 22,5 million kilometers (14 million miles) across – about the size of Mercury’s orbit. But this is just the black hole itself.

All of the mass trying to get into the black hole – called the accretion disk – forms a disk that has 4.6 million times the mass of our Sun and would fit inside the orbit of the Earth. Though like other black holes, Sgr A* tries to consume anything that happens to be nearby, star formation has been detected near this behemoth astronomical phenomenon.

8. It’s Almost as Old as the Universe Itself:

The most recent estimates place the age of the Universe at about 13.7 billion years. Our Milky Way has been around for about 13.6 billion of those years, give or take another 800 million. The oldest stars in our the Milky Way are found in globular clusters, and the age of our galaxy is determined by measuring the age of these stars, and then extrapolating the age of what preceded them.

Though some of the constituents of the Milky Way have been around for a long time, the disk and bulge themselves didn’t form until about 10-12 billion years ago. And that bulge may have formed earlier than the rest of the galaxy.

9. It’s Part of the Virgo Supercluster:

As big as it is, the Milky Way is part of an even larger galactic structures. Our closest neighbors include the Large and Small Magellanic Clouds, and the Andromeda Galaxy – the closest spiral galaxy to the Milky Way. Along with some 50 other galaxies, the Milky Way and its immediate surroundings make up a cluster known as the Local Group.

A mosaic of telescopic images showing the galaxies of the Virgo Supercluster. Credit: NASA/Rogelio Bernal Andreo
A mosaic of telescopic images showing the galaxies of the Virgo Supercluster. Credit: NASA/Rogelio Bernal Andreo

And yet, this is still just a small fraction of our stellar neighborhood. Farther out, we find that the Milky Way is part of an even larger grouping of galaxies known as the Virgo Supercluster. Superclusters are groupings of galaxies on very large scales that measure in the hundreds of millions of light years in diameter. In between these superclusters are large stretches of open space where intrepid explorers or space probes would encounter very little in the way of galaxies or matter.

In the case of the Virgo Supercluster, at least 100 galaxy groups and clusters are located within it massive 33 megaparsec (110 million light-year) diameter. And a 2014 study indicates that the Virgo Supercluster is only a lobe of a greater supercluster, Laniakea, which is centered on the Great Attractor.

10. It’s on the move:

The Milky Way, along with everything else in the Universe, is moving through space. The Earth moves around the Sun, the Sun around the Milky Way, and the Milky Way as part of the Local Group, which is moving relative to the Cosmic Microwave Background (CMB) radiation – the radiation left over from the Big Bang.

The CMB is a convenient reference point to use when determining the velocity of things in the universe. Relative to the CMB, the Local Group is calculated to be moving at a speed of about 600 km/s, which works out to about 2.2 million km/h. Such speeds stagger the mind and squash any notions of moving fast within our humble, terrestrial frame of reference!

We have written many interesting articles about the Milky Way for Universe Today. Here’s 10 Interesting Facts about the Milky Way, How Big is the Milky Way?, What is the Closest Galaxy to the Milky Way?, and How Many Stars Are There in the Milky Way?

For many more facts about the Milky Way, visit the Guide to Space, listen to the Astronomy Cast episode on the Milky Way, or visit the Students for the Exploration and Development of Space at seds.org.

Rise of the Mega Rockets: Comparing Heavy Lift Launch Systems

An Ariane 5 heads spaceward. Credit: Ariane.tv screenshot.

A new generation of space rockets ready to lift new and exciting payloads spaceward is coming to a sky near you.

Tomorrow, a Delta IV Heavy rocket will boost the Orion space capsule on a two orbit journey around the Earth that will test key systems. And though tomorrow’s launch is uncrewed, the Orion Command Module will one day form the core of NASA’s Orion MPCV Multi-Purpose Crew Vehicle and is slated to care out humanity’s first mission to an asteroid and beyond in the next decade.

But a second, lesser known launch also leaves Earth tomorrow as well, atop a rocket that will soon give way to a new generation of lift boosters as launch services vie for new customers. Just over eight hours after the launch of EFT-1, an Ariane 5 rocket lifts off from French Guiana with GSAT-16.

Credit Jason Major.
The EFT-1 Delta IV Heavy posed for roll out. Credit: Jason Major. @JPMajor

Is the ‘battle of the boosters’ heating up?

This comes after the December 2nd announcement earlier this week by participating members of the European Space Agency to proceed with the development of the next generation Ariane 6 rocket. Also included in the 5.9 billion Euro (7.3 billion USD) budget proposal  is funding for the 2018 ExoMars mission, along with further support of ESA’s International Space Station commitments.

To date, ESA has fielded five of its Automated Transfer cargo Vehicles (ATVs) on missions to the International Space Station. ESA will also design the Service Module segment of the Orion MPCV.

“I can summarize this ministerial council by say it was a success… I’d even go so far as to say that it is a great success,” said Jean-Jacques Dordain, the director-general of the European Space Agency.

The Ariane 6 is expected to be on the launch pad by 2020, and will feature two variants capable of placing 5 to 11 tonnes in a geostationary transfer orbit. The solid fuel booster to be incorporated will be based on the Vega rocket design, while the upper stage Vinci engine is already currently in development.

Ariane 6. Credit Wikimedia Commons, SkywalkerPL.
A look at the Ariane 6 rocket. Credit Wikimedia Commons, SkywalkerPL.

The design has been hotly contested among European Space Agency members, many of whom are in favor of other variants based on the upgraded Ariane 5. Some of the largest rockets of all time included those developed by NPO Energia, capable of lofting 100,000 kilograms into low Earth orbit. An Energia N1 Moon rocket exploded on the pad on July 3rd 1969, effectively ending the Soviet Union’s bid to put a man on the Moon. In comparison,   the massive Saturn V rocket — thus far, the largest and most powerful ever fielded by the United States  — could deploy the equivalent of 118,000 kg to low Earth orbit and 47,000 kg to a Trans-Lunar Insertion orbit around the Moon.

But that’s just the beginning. Though the Orion capsule will ride atop a United Launch Services Delta IV Heavy tomorrow — a system usually employed for launching clandestine spy satellites — NASA hopes to have its own Space Launch System (SLS) rocket sitting on the pad by the end of 2018. Boeing was awarded the contract for SLS earlier this year, and the system largely rose re-imagined from the ashes of the cancelled Constellation program. The SLS Block 1 is expected to have a lift capacity of 70,000 kg to LEO, while Boeing’s proposed SLS Block 2 variant would, if fielded, have the largest lift capacity of all time at 130,000 kg to LEO. Only the Long March 9 proposed by China approaches that lofty goal.

Credit: NASA.
An artist’s concept of Orion headed towards deep space. Credit: NASA.

And the wild card is Elon Musk’s SpaceX. Already in the game of sending cargo via its Dragon spacecraft to the ISS, SpaceX is developing a reputation for dependability when it comes to getting satellites into orbit at relatively low cost. SpaceX hopes to field its Falcon 9 Heavy with a lift capacity of 53,000 kg to LEO sometime in 2015, and many proposed missions are banking on the the Falcon 9 Heavy as a future service provider for solar system exploration.  Certainly, with the recent failure of the Antares rocket on October 28th, SpaceX may look like the more attractive option to many, and the development of the Ariane 6 is expected to face stiff competition in the brave new world of high tech rocketry.

Ever wonder what all of these launch vehicles and spacecraft past and present look like stacked up against each other? There’s a graphic for that, recently featured on Io9:

Credit: Heaney555
A breakdown and comparison of spacecraft launch systems. Click to enlarge. Credit: Reddit user Heaney555.

From Almaz to Zarya, this is a fascinating study in scale comparison. Be sure to zoom in and check out the tiny ant-like crew compliment of each, also to scale. Of course, the backyard satellite-tracker in us can’t help be notice the brightness-versus size comparison for many of these. For example, the International Space Station on a good pass can appear as bright as Venus at -4th magnitude — and even look “TIE Fighter shaped” in binoculars — while the smaller Shenzhou and Soyuz modules are often barely visible as they pass overhead. And how we miss watching the Shuttle paired with the International Space Station as they both glided silently by:

But such orbital drama can still be caught if you know when and where to look for it. And speaking of which, viewers in western Australia and the southwestern United States may be able to see Orion and EFT-1 on its first lap around the Earth tomorrow before it fires its engines over the Atlantic headed for a 5,800 km apogee over southern Africa. Assuming EFT-1 lifts off at the beginning of its 159 minute launch window at 7:05 AM EST/12:05 UT, expect it to see it crossing dusk skies over western Australia at 55 minutes after liftoff, and dawn skies for the southwestern U.S. at 95 minutes post-launch respectively.

An awesome sight to behold indeed, marking the start of a brave new era of space exploration.

So what do you, the astute and space-minded reader of Universe Today think? Are the SLS and its kin the lift vehicle(s) of the future, or ‘rockets to nowhere?’ Will they survive the political winds that are bound to blow over the coming decade? Will the Ariane 6 best the Falcon 9 as the lift platform of choice?

One thing is for sure, expect coverage of space exploration drama and more to continue here at Universe Today!