The Sun provides energy for life here on Earth through light and heat. Credit: NASA Goddard Space Flight Center
How far is the Sun? It seems as if one could hardly ask a more straightforward question. Yet this very inquiry bedeviled astronomers for more than two thousand years.
Certainly it’s a question of nearly unrivaled importance, overshadowed in history perhaps only by the search for the size and mass of the Earth. Known today as the astronomical unit, the distance serves as our reference within the solar system and the baseline for measuring all distances in the Universe.
Thinkers in Ancient Greece were among the first to try and construct a comprehensive model of the cosmos. With nothing but naked-eye observations, a few things could be worked out. The Moon loomed large in the sky so it was probably pretty close. Solar eclipses revealed that the Moon and Sun were almost exactly the same angular size, but the Sun was so much brighter that perhaps it was larger but farther away (this coincidence regarding the apparent size of the Sun and Moon has been of almost indescribable importance in advancing astronomy). The rest of the planets appeared no larger than the stars, yet seemed to move more rapidly; they were likely at some intermediate distance. But, could we do any better than these vague descriptions? With the invention of geometry, the answer became a resounding yes. Continue reading “How Did We Find the Distance to the Sun?”
A splendid capture of comet Q2 Lovejoy as it passes near M79 at the end of 2014. Credit and copyright: Andre van der Hoeven.
Have you seen the amazing pics? A bright comet graces evening skies this month, assuring that 2015 is already on track to be a great year for astronomy.
We’re talking about Comet C/2014 Q2 Lovejoy. Discovered by comet hunter extraordinaire Terry Lovejoy on August 17th, 2014, this denizen of the Oort Cloud has already wowed observers as it approaches its passage perihelion through the inner solar system in the coming week.
First, our story thus far. We’ve been following all Comet Q2 Lovejoy action pretty closely here at Universe Today, from its surreptitious brightening ahead of schedule, to its recent tail disconnection event, to its photogenic passage past the +8.6 magnitude globular cluster Messier 79 (M79) in the constellation Lepus. We also continue to be routinely blown away by reader photos of the comet. And, like the Hare for which Lepus is named, Q2 Lovejoy is now racing rapidly northward, passing into the rambling constellation of Eridanus the River before entering the realm of Taurus the Bull on January 9th and later crossing the ecliptic plane in Aries.
The path of Comet Q2 Lovejoy from January 2nd to the 31st. Ticks mark the position of the comet at 7PM EST/midnight Universal Time. Credit: Created using Starry Night Education software.
And the best window of opportunity for spying the comet is coming right up. We recently caught our first sight of Q2 Lovejoy a few evenings ago with our trusty Canon 15x 45 image-stabilized binocs from Mapleton, Maine. Even as seen from latitude 47 degrees north and a frosty -23 Celsius (-10 Fahrenheit) — a far cry from our usual Florida based perspective — the comet was an easy catch as a bright fuzz ball. Q2 Lovejoy was just outside of naked eye visibility for us this week, though I suspect that this will change as the Moon moves out of the evening picture this weekend.
Currently shining at magnitude +5.5, Comet Q2 Lovejoy has already been spied by eagle-eyed observers unaided from dark sky sites to the south. Astrophotographers have revealed its long majestic dust and ion tails, as well as the greenish hue characteristic of bright comets. That green color isn’t kryptonite, but the fluorescing of diatomic carbon and cyanogen gas shed by the comet as it’s struck by ultraviolet sunlight. This greenish color is far more apparent in photographs, though it might just be glimpsed visually if the intrinsic brightness of the coma exceeds expectations. Q2 Lovejoy just passed opposition at 0.48 AU from the Earth today on January 2nd, and will make its closest passage from our fair world on January 7th at 0.47 AU (43.6 million kilometres) distant.
Comet Q2 Lovejoy via Iphone (!) and a NexStra 8SE telescope. Credit and copyright: Andrew Symes.
What’s so special about the coming week? Well, we also cross a key milestone for evening observing, as the light-polluting Moon reaches Full phase on Sunday January 5th at 4:54 UT (11:54 PM EDT on the 4th) and begins sliding out of the evening sky on successive evenings. That’s good news, as Comet Q2 Lovejoy enters the “prime time” evening sky and culminates over the southern horizon at around 10:30 PM local this weekend, then 8:00 PM on January the 15th, and just before 6:00 PM by January 31st.
While many comets put on difficult to observe dusk or dawn appearances — the 2013 apparition of another comet, C/2011 L4 PanSTARRS comes to mind — Q2 Lovejoy is well placed this month in the early evening hours.
The current projected peak brightness for Comet Q2 Lovejoy is +4th magnitude right around mid-January. Already, the comet is bright enough and well-placed to the south for northern hemisphere observers that it’s possible to catch astrophotos of the comet along with foreground objects. If you’ve got a tripod mounted DSLR give it a try… it’s as simple as aiming, focusing manually with a wide field of view, and taking 10 to 30 second exposures to see what turns up. Longer shots will call for sky tracking via a barn-door or motorized mount. Binoculars are you friend in your comet-hunting quest, as they can be readily deployed in sub-zero January temps and provide a generous field of view.
Q2 Lovejoy will also pass near the open clusters of the Hyades and the Pleiades through mid-January, and cross into the constellations of Aries and Triangulum by late January before heading northward to pass between the famous Double Cluster in Perseus and the Andromeda Galaxy M31 in February, proving further photo ops.
From there, Q2 Lovejoy is expected to drop below naked eye visibility in late February before passing very near the North Star Polaris and the northern celestial pole at the end of May on its way out of the inner solar system on its 8,000 year journey.
So, although 2014 didn’t produce the touted “comet of the century,” 2015 is already getting off to a pretty good start in terms of comets. We’re out looking nearly every clear night, and the next “big one” could always drop by at anytime… but hopefully, the first discovery baring the name “Comet Dickinson” will merely put on a spectacular show, and not prove to be an extinction level event…
Collisions of neutron stars produce powerful gamma-ray bursts – and heavy elements like gold (Credit: Dana Berry, SkyWorks Digital, Inc.)
It’s known as HIP 85605, one of two stars that make up a binary in the Hercules constellation roughly 16 light years away. And if a recent research paper produced by Dr. Coryn Bailer-Jones of the Max Planck Institute for Astronomy in Heidelberg, Germany is correct, it is on a collision course with our Solar System.
Now for the good news: according to Bailer-Jones’ calculations, the star will pass by our Solar System at a distance of 0.04 parsecs, which is equivalent to 8,000 times the distance between the Earth and the Sun (8,000 AUs). In addition, this passage will not affect Earth or any other planet’s orbit around the Sun. And perhaps most importantly of all, none of it will be happening for another 240,000 to 470,000 years from now.
“Even though the galaxy contains very many stars,” Bailer-Jones told Universe Today via email, “the spaces between them are huge. So even over the (long) life of our galaxy so far, the probability of any two stars have actually collided — as opposed to just coming close — is extremely small.”
However, in astronomical terms, that still counts as a near-miss. In a universe that is 46 billion light years in any direction – and that’s just the observable part of it – an event that is expected to take place just 50 light days away is considered to be pretty close. And in the context of space and time, a quarter of a million to half a million years is the very near future.
The real concern is the effect that the passage of HIP 85605 could have on the Oort Cloud – the massive cloud of icy planetesimals that surrounds the Solar System. Given that it’s distance is between 20,000 and 50,000 AU from our Sun, HIP 85605 would actually move through the Oort cloud and cause serious disruption.
The layout of the Solar System, including the Oort Cloud, which lies 50,000 AU from our Sun. Credit: NASA
Many of these planetesimals could be blown off into space, but others could be sent hurtling towards Earth. Assuming humanity is still around at this point in time, this could present a bit of an inconvenience, even if it is spread over the course of a million years.
As it stands, such “close encounters” between stars are quite rare. Stellar collisions usually only occur within binaries, where white dwarfs or neutron stars are concerned. “The exception to this is physically bound binary stars in a tight orbit,” said Bailer-Jones. “It can and does happen that one star expands during its evolution and will then interfere with the evolution of the other star. Neutron-neutron star pairs can even merge.”
But of course, on an astronomical timescale, stars passing each other by as they perform their cosmic dance is actually a pretty common occurrence. As part of Bailer-Jones larger study of over 50,000 stars within our galaxy, this “close encounter” is one of several predicted to take place in the coming years.
Of all of them, only HIP 85605 is expected to come within a single parsec between 240 and 470 thousand years from now. He also indicates with (90% confidence) that the last time such an encounter took place was 3.8 million years ago when gamma Microscopii – a G7 giant which has two and a half times the mass of our Sun – came within 0.35-1.34 pc of our system, which may have caused a large perturbation in the Oort cloud.
Tightly bound binary stars, like the ones illustrated here, sometimes result in stellar collisions. Credit: Chandra
On his MPIA webpage, in the study’s FAQ section, Bailer-Jones claims that his research into stellar close encounters was motivated by a desire to study the potential impacts of astronomical phenomena on Earth, and is part of a larger program named “astroimpacts”.
“I am interested in the history of the Earth,” he says, “and astronomical phenomena have clearly played a role in this. But what role precisely, how significant, and what can we expect to happen in the future?” Whereas several studies have been conducted in the past, he feels that the methods – which include assuming a linear relative motion of stars – produces inaccurate results.”
In contrast, Bailer-Jones study relies on “more recent data or re-analyses of data to produce hopefully more accurate results, and then compensate more rigorously for the uncertainties in the data, so that I can attach probabilities to my statements.”
As a result of this, he predicts that HIP 85605 has a 90% chance of passing within a single parsec of our Sun in the next 240 to 470 thousands years. However, he also admits that if the astronomy is incorrect, the next closest encounter won’t be happening for another 1.3 million years, when a K7 dwarf known as GL 710 is predicted to pass within 0.10 – 0.44 parsecs.
Bailer-Jones also believes that the European Space Agency’s Gaia spacecraft will help make more accurate predictions in the future. By understanding and mapping the environment of the Milky Way Galaxy, measuring the gravitational potential and determining the velocity of stars, scientists will be able to see how their various orbits around the galaxy’s center could cause them to intersect.
It is likely that passing stars have a system of exoplanets (like Kepler-186f pictured here), which would place them within a few parsecs of Earth. Image Credit: NASA Ames/SETI Institute/JPL-CalTech
But perhaps the most interesting question explored on his webpage is the possibility of using stellar close encounters as a shortcut for exploring exoplanets. According to current cosmological models, the majority of stars within our galaxy are believed to host exoplanets.
So if a star is passing us at just a few parsecs (or even with a single parsec) why not hop on over and investigate its planets? Well, as Bailer-Jones indicates, that’s not really a practical idea: “Traveling to a star passing our solar system at a distance of around 1 pc with a relative speed of 30 km/s is no easier than traveling the the nearby stars (the nearest of which is just over 1 pc away). And we would have to wait 10s of thousands of years for the next encounter. If we can ever achieve interstellar travel, I don’t suppose it would take that long to achieve, so why wait?”
Darn. Still, if there’s one thing this phenomena and Bailer-Jones study reminds us, it is that in the course of dancing around the center of the Milky Way, stars are not fixed in a single point in space. Not only do they periodically move within reach of each other, they can also have an affect on life within them.
Alas, the timescale on which such things happen, not to mention the consequences they entail, are so large that people here on Earth need not worry. By the time HIP 85605 or GL 710 come within a parsec or two of us, we’ll either be long-since dead or too highly evolved to care!
*Update: According to a new study posted by Erick E. Mamajek and associates on arXiv, the passage of the recently-discovered low mass star W0720 (aka. “Scholtz Star”) – roughly 70,000 years ago and at a distance of 0.25 Parsecs from our Sun – was the closest encounter our Solar System has had with another star. They calculate the possibility that it would have penetrated the System’s Outer Oort Cloud at 98%. However, they also estimate that the impact it would have had on the flux of long-period comets was negligible, but that the passage also highlights how “dynamically important Oort Cloud perturbers may be lurking among nearby stars”.
Having read the study, Bailer-Jones claims on the updated FAQ section of his MPIA webpage that their analysis appears to be correct. Based on the assumption that the star was moving on a constant velocity relative to the Sun prior to the encounter, he agrees that the calculations on the distances and timing of the passage are valid. While his own study identified a possible closer encounter (Hip 85605), he reiterates that the data on this star is of poor quality. Meanwhile, another close encounter took place involving Hip 89825; but here, the approach distance is estimated to have been 0.02 Parsecs larger. Hence, W0720 can be said to have been the closest encounter with some degree of certainty at this time.
A Soyuz-2 rocket lifts off from Kourou on April 3, 2014, with Sentinel-1A satellite. Credit: ESA
2014 was a banner year for the Russian Space Agency, with a record-setting fourteen launches of the next generation unmanned Soyuz-2 rocket. A number of other firsts took place in the course of the year as well, cementing the Soyuz family of rockets as the most flown and most reliable rocket group ever.
But already it seems as though the new year will be an even better year, with a full 20 missions already scheduled to take place, a number of them holdovers from 2014.
The Soyuz 2 launcher currently operates alongside the Soyuz-U (mainly used for launching the unmanned Progress Resupply Spacecraft to the International Space Station) and the Soyuz FG (primarily used for human flights with the Soyuz Spacecraft for missions to ISS), but according to Spaceflight 101, the Soyuz 2 will eventually replace the other vehicles once they are phased out.
In fact, in October of 2014, the Soyuz 2 had its first launch of a Progress cargo spacecraft. Other achievements were that the last two launches of the year were conducted without the aid of DM blocks – a derivative of the Blok D upper stage launch rocket developed during the 1960’s.
As Leonid Shalimov, the CEO of NPO Avtomatiki, the Russian electronic engineering and research organization, said in an interview with the government-owned Russian news agency TASS: “Fourteen launches of Soyuz-2 were carried out in 2014 – a record number in the company history,” he said. “Meanwhile, a total of 19 launches were planned in the outgoing year, five have been postponed till 2015.”
Soyuz-2 rocket preparing to launch from the Plesetsk Cosmodrome in June, 2013. Image Credit: Russian Space News
As a leader in the development of radio-electronic equipment and rocket space systems, the company is behind the development of a number of automated and integrated control systems that are used in space, at sea, heavy industry, and by oil and natural gas companies.
However, it is arguably the company’s work with Soyuz-2 rockets that has earned the most attention. As a general designation for the newest version of the rocket, the Soyuz-2 is essentially a three-stage rocket carrier and will be used to transport crews and supplies into Low Earth Orbit (LEO).
Compared to previous generations of the rocket, the Soyuz-2 features updated engines with improved injection systems on the first-stage boosters, as well as the two core engine stages.
Unlike previous incarnations, the Soyuz-2 can also be launched from a fixed launched platform since they are capable of performing rolls while in flight to change their heading. The old analog control systems have also been upgraded with a new digital flight control and telemetry systems that can adapt to changing conditions in mid-flight.
The Advanced Crew Transportation System, a next-generation reusable craft intended for a Russian lunar mission in 2028. Credit: TASS
In total, some 42 launches of this rocket have taken place over the past decade, the first taking place on November 8th, 2004 from the Plesetsk Cosmodrome – located about 200 km outside of Archangel.
The majority of launches were for the sake of deploying weather, observation and communication satellites.
Long-term, the Soyuz-2 is also expected to play a key role in Russia’s plan for a manned lunar mission, which is tentatively scheduled to take place in 2028.
The only people who'll be floating above the floor on January 4th are the astronauts on board the International Space Station. This photo shows onboard the NASA KC-135 that uses a special parabolic pattern to create brief periods of microgravity
When I first heard we were all going to float in the air at 9:47 a.m. PST on January 4th, 2015 I laughed, figuring this latest Internet rumor would prove too silly to spread very far. Boy, was I wrong. This week the bogus claim has already been shared over a million times on Facebook. Now I’m being asked if it’s true. It all started on December 15th when the Daily Buzz Live, famous for fake news, published this tweet purportedly from NASA:
Well-crafted but fake tweet created by Daily Buzz Live. Credit: Daily Buzz Live
Sure looks real. Even has a cool, doomsday-flavored hashtag #beready. The story attributes the prediction to British astronomy popularizer Patrick Moore, who must be chuckling in his grave because he passed away in 2012. The story goes on. A rare planetary alignment of Jupiter and Pluto “will mean that the combined gravitational force of the two planets would exert a stronger tidal pull, temporarily counteracting the Earth’s own gravity and making people virtually weightless.”
But when it comes down to it, Zero Gravity Day is just a lot of warmed-over hoo-ha. Let’s sort out what’s fact and what’s fancy in this claim.
Sir Patrick Moore, one of the world’s greatest astronomy popularizers. He wrote more than 70 books and was the host of the long-running BBC TV series “The Sky at Night”.
True: Patrick Moore did make this claim in a BBC radio program on April 1, 1976 … as an April Fools Day joke! The article doesn’t bother to mention this significant detail. Ever so sly, Moore fibbed about the details of the purported alignment. Pluto was in Virgo and Jupiter in Pisces on that date, exactly opposite one another in the sky and as far out of alignment as possible. Gullible to suggestion, hundreds of listeners phoned in to the BBC saying they’d experienced the decrease in gravity. One woman said she and 11 friends had been “wafted from their chairs and orbited gently around the room”.
Martin Wainwright, who edited the book The Guardian Book of April Fool’s Day(published by the British newspaper The Guardian), described Moore as the ideal presenter with his “weight delivery” lending an added “air of batty enthusiasm that only added to his credibility”. The Daily Buzz updated the joke and gave it even more credibility by wrapping it up in “bacon” — a fake NASA tweet.
False: Jupiter and Pluto will not be in alignment on January 4th. Pluto is hidden the solar glare in Sagittarius at the moment, while Jupiter shines nearly halfway across the zodiac in Leo. Far, far apart.
False: Planetary alignments will not make you weightless. Not even if all the planets and Sun aligned simultaneously. While the gravity of a place is Jupiter is HUGE and will crush you if you could find a surface to stand on, the distance between Earth and Jupiter (and all the other planets for that matter) is enormous. This waters down gravity in a big way. Jupiter tugs on you personally with the same gravitational force as a compact car three feet (1-meter) away. As for Pluto, it’s almost 60 times smaller than Jupiter with a gravitational reach that can only be described as virtually ZERO.
The Moon is by far the dominant extraterrestrial gravity tractor among the planets and moons of the Solar System because it’s relatively close to Earth. According to Phil Plait, author of the Bad Astronomer blog: “Even if you add all of the planets together, they pull on you with a force less than 2% of that of the Moon.”
Total solar eclipse in 1999. The alignment of the nearby Moon and massive Sun, the weightiest body in the Solar System by far, didn’t cause anyone to float off the ground. To my knowledge. Credit: Luc Viatour
The Sun also has a significant gravitational effect on Earth, but when was the last time you heard of people floating in the air during a total solar eclipse? If our strongest gravitational neighbors can’t loft you off your feet then don’t look to Jupiter and Pluto. Not that I wish this wouldn’t happen as it would provide a fitting physical aspect to what for many is a spiritual phenomenon.
There are countless claims on the Internet that alignments of comets, planets and fill-in-the-blanks produce earthquakes, deadly meteor storms, bad juju and even endless hiccups. It’s all pseudoscientific hogwash. Either deliberately made up by to lead you astray or because someone hasn’t checked the facts and simply passes on what they’ve heard. The stuff spreads like a virus, wasting our time and bandwidth and distracting our attention from the real beauty and bizarreness of the cosmos.
How to stop it? Critical thinking. If this skill were at the top of the list of subjects taught in high school, we’d live on a very different planet. Maybe I’m dreaming. Maybe we’ll always be gullible to snake-oil claims. But I’d like to believe that a basic knowledge of science coupled with the ability to analyze a claim with a critical eye will go a long way toward extinguishing bogus scientific claims before they spread like wildfire.
Come this Sunday at 9:47 a.m. PST allow me to suggest that instead of waiting to float off the ground, tell your family and friends about the amazing Full Wolf Moon that will shine down that evening from the constellation Gemini. If it’s magic you’re looking for, a a walk in winter moonlight might do the trick.
We see the Moon differently depending upon the wavelength in which we view it. Top row from left:
“By the Light of the Silvery Moon” goes the song. But the color and appearance of the Moon depends upon the particular set of eyes we use to see it. Human vision is restricted to a narrow slice of the electromagnetic spectrum called visible light.
With colors ranging from sumptuous violet to blazing red and everything in between, the diversity of the visible spectrum provides enough hues for any crayon color a child might imagine. But as expansive as the visual world’s palette is, it’s not nearly enough to please astronomers’ retinal appetites.
Visible light is a sliver of light’s full range of “colors” which span from kilometers-long, low-energy radio waves (left) to short wavelength, energetic gamma rays. It’s all light, with each color determined by wavelength. Familiar objects along the bottom reference light wave sizes. Visible light waves are about one-millionth of a meter wide. Credit: NASA
Since the discovery of infrared light by William Herschel in 1800 we’ve been unshuttering one electromagnetic window after another. We build telescopes, great parabolic dishes and other specialized instruments to extend the range of human sight. Not even the atmosphere gets in our way. It allows only visible light, a small amount of infrared and ultraviolet and selective slices of the radio spectrum to pass through to the ground. X-rays, gamma rays and much else is absorbed and completely invisible.
Earth’s atmosphere blocks a good portion of light’s diversity from reaching the ground, the reason we launch rockets and orbiting telescopes into space. Large professional telescopes are often built on mountain tops above much of the denser, lower atmosphere. This expands the viewing “window” into the infrared. Credit: NASA
To peer into these rarified realms, we’ve lofting air balloons and then rockets and telescopes into orbit or simply dreamed up the appropriate instrument to detect them. Karl Jansky’s homebuilt radio telescope cupped the first radio waves from the Milky Way in the early 1930s; by the 1940s sounding rockets shot to the edge of space detected the high-frequency sizzle of X-rays. Each color of light, even the invisible “colors”, show us a new face on a familiar astronomical object or reveal things otherwise invisible to our eyes.
So what new things can we learn about the Moon with our contemporary color vision?
Radio Moon
Radio: Made using NRAO’s 140-ft telescope in Green Bank, West Virginia. Blues and greens represent colder areas of the moon and reds are warmer regions. The left half of Moon was facing the Sun at the time of the observation. The sunlit Moon appear brighter than the shadowed portion because it radiates more heat (infrared light) and radio waves.
Submillimeter Moon
Submillimeter: Taken using the SCUBA camera on the James Clerk Maxwell Telescope in Hawaii. Submillimeter radiation lies between far infrared and microwaves. The Moon appears brighter on one side because it’s being heated by Sun in that direction. The glow comes from submillimeter light radiated by the Moon itself. No matter the phase in visual light, both the submillimeter and radio images always appear full because the Moon radiates at least some light at these wavelengths whether the Sun strikes it or not.
Mid-infrared Moon
Mid-infrared: This image of the Full Moon was taken by the Spirit-III instrument on the Midcourse Space Experiment (MSX) at totality during a 1996 lunar eclipse. Once again, we see the Moon emitting light with the brightest areas the warmest and coolest regions darkest. Many craters look like bright dots speckling the lunar disk, but the most prominent is brilliant Tycho near the bottom. Research shows that young, rock-rich surfaces, such as recent impact craters, should heat up and glow more brightly in infrared than older, dust-covered regions and craters. Tycho is one of the Moon’s youngest craters with an age of just 109 million years.
Near-infrared Moon
Near-infrared: This color-coded picture was snapped just beyond the visible deep red by NASA’s Galileo spacecraft during its 1992 Earth-Moon flyby en route to Jupiter. It shows absorptions due to different minerals in the Moon’s crust. Blue areas indicate areas richer in iron-bearing silicate materials that contain the minerals pyroxene and olivine. Yellow indicates less absorption due to different mineral mixes.
Visible light Moon
Visible light: Unlike the other wavelengths we’ve explored so far, we see the Moon not by the light it radiates but by the light it reflects from the Sun.
The iron-rich composition of the lavas that formed the lunar “seas” give them a darker color compared to the ancient lunar highlands, which are composed mostly of a lighter volcanic rock called anorthosite.
UV Moon
Ultraviolet: Similar to the view in visible light but with a lower resolution. The brightest areas probably correspond to regions where the most recent resurfacing due to impacts has occurred. Once again, the bright rayed crater Tycho stands out in this regard. The photo was made with the Ultraviolet Imaging Telescope flown aboard the Space Shuttle Endeavour in March 1995.
X-ray Moon
X-ray: The Moon, being a relatively peaceful and inactive celestial body, emits very little x-ray light, a form of radiation normally associated with highly energetic and explosive phenomena like black holes. This image was made by the orbiting ROSAT Observatory on June 29, 1990 and shows a bright hemisphere lit by oxygen, magnesium, aluminum and silicon atoms fluorescing in x-rays emitted by the Sun. The speckled sky records the “noise” of distant background X-ray sources, while the dark half of the Moon has a hint of illumination from Earth’s outermost atmosphere or geocorona that envelops the ROSAT observatory.
Gamma ray Moon
Gamma rays: Perhaps the most amazing image of all. If you could see the sky in gamma rays the Moon would be far brighter than the Sun as this dazzling image attempts to show. It was taken by the Energetic Gamma Ray Experiment Telescope (EGRET). High-energy particles (mostly protons) from deep space called cosmic rays constantly bombard the Moon’s surface, stimulating the atoms in its crust to emit gamma rays. These create a unique high-energy form of “moonglow”.
Astronomy in the 21st century is like having a complete piano keyboard on which to play compared to barely an octave a century ago. The Moon is more fascinating than ever for it.
A new Avengers movie. A reboot of the Star Wars franchise. The final installment of the Hunger Games. The Martian makes it to the big screen. Yup, even if the zombie apocalypse occurs in 2015, it’ll still be a great year. But trading science fiction for fact, we’re also on track for a spectacular year in space science and exploration as well.
Humanity will get its first good look at Ceres and Pluto, giving us science writers some new pics to use instead of the same half dozen blurry dots and artist’s conceptions. SpaceX will also attempt a daring landing on a sea platform, and long duration missions aboard the International Space Station will get underway. And key technology headed to space and on Earth may lead the way to opening up the window of gravitational wave astronomy on the universe. Here’s 10 sure-fire bets to watch for in the coming year from Universe Today:
LISA Pathfinder deployed at L1. Credit: ESA/Artist’s concept.
10. LISA Pathfinder
A precursor to a full-fledged gravitational wave detector in space, LISA Pathfinder will be launching atop a Vega rocket from Kourou, French Guiana in July 2015. LISA stands for the Laser Interferometer Space Antenna, and the Pathfinder mission will journey to the L1 Lagrange point between the Earth and the Sun to test key technologies. LISA Pathfinder will pave the way for the full fledged LISA space platform, a series of three free flying spacecraft proposed for launch in the 2030s.
Looking down one of the arms of LIGO Hanford. Credit: Photo by author.
9. AdLIGO Goes Online
And speaking of gravitational waves, we may finally get the first direct detection of the same in 2015, when Advanced LIGO is set to go online. Comprised of two L-shaped detectors, one based in Livingston Louisiana, and another in Hanford Washington, AdLIGO will feature ten times the sensitivity of the original LIGO observatory. In fact, as was the case of the hunt for the Higgs-Boson by CERN, a non-detection of gravitational waves by AdLIGO would be a much stranger result!
A replica of the Hubble Space Telescope on display at the Kennedy Space Center. Credit: Photo by author.
8. Hubble Turns 25
Launched on April 24th, 1990 aboard the Space Shuttle Discovery, the Hubble Space Telescope celebrates 25 years in space in 2015. The final servicing mission in 2009 gave Hubble a reprieve from the space junk scrap heap, and the orbiting telescope is still going strong. Hubble has no less than pushed the limits in modern astronomy to become a modern icon of the space age.
MESSENGER wraps up its mission in 2015. Credit: NASA/MESSENGER/JPL/APL.
7. The End of MESSENGER
NASA’s Mercury exploring spacecraft wraps up its mission next year. Launched in 2004, MESSENGER arrived in orbit around Mercury after a series of flybys on March 18th, 2011. MESSENGER has mapped the innermost world in detail, and studied the space environment and geology of Mercury. In late March 2015, MESSENGER will achieve one final first, when it impacts the surface of Mercury at the end of its extended mission.
Akatsuki on Earth prior to departure. Credit: JAXA.
6. Akatsuki at Venus
This Japanese spacecraft missed orbital insertion a few years back, but gets a second chance at life in 2015. Launched in 2010 atop an H-IIA rocket from the Tanegashima Space Center in Japan, Akatsuki failed to enter orbit around Venus at the end of 2010, and instead headed out for a heliocentric path around the Sun. Some quick thinking by JAXA engineers led to a plan to attempt to place Akatsuki in Venusian orbit in November 2015. This would be a first for the Japanese space agency, as attempts by JAXA at placing a spacecraft in orbit around another planet – including the Mars Nozomi probe – have thus far failed.
The target for the Falcon-9 first stage later next week. Credit: SpaceX.
5. SpaceX to Attempt to Land on a Sea Platform
It’ll definitely rock if they pull it off next week: on January 6th, a SpaceX Falcon 9 rocket will lift off from Cape Canaveral with its Dragon spacecraft headed to the International Space Station on mission CRS-5. Sure, these resupply missions are becoming routine, but after liftoff, SpaceX is attempting something new and daring: landing the Falcon-9 first stage Buck Rodgers style, “fins first” on a floating barge. This is the next step in ultimately proving the feasibility of having the rocket fly back to the launch site for eventual reuse. If nothing else, expect some stunning video of the attempt soon!
An artist’s concept of an asteroid retrieval mission. Credit: NASA.
4. NASA to Decide on an Asteroid Mission
Some major decisions as to the fate and the future of manned space exploration are due next year, as NASA is expected to decide on the course of action for its Asteroid Redirect Mission. The current timeline calls for the test of the SLS rocket in 2018, and the launch of a spacecraft to recover an asteroid and place it in orbit around the Moon in 2019. If all goes according to plan – a plan which could always shift with the political winds and future changes in administrations – we could see astronauts exploring a captured asteroid by the early 2020s.
Astronaut Scott Kelly (left), and cosmonaut Mikhail Korniyenko. Credit: NASA/Roscomos.
3. Long Duration ISS Missions
Beginning in 2015, astronauts and cosmonauts will begin year-long stays aboard the ISS to study the effects of long duration space missions. In March of 2015, cosmonaut Mikhail Korniyenko and U.S. astronaut Scott Kelly will launch as part of Expedition 43 headed to the ISS. The Russians have conducted stays in space longer than a year aboard the Mir space station, but Kelly’s stay aboard the ISS will set a duration record for NASA astronauts. Perhaps, a simulated “Mars mission” aboard the ISS could be possible in the coming years?
An artist’s concept of Dawn approaching 1 Ceres. Credit: NASA/JPL.
2. Dawn at Ceres
Fresh off of exploring Vesta, NASA’s Dawn spacecraft will become the first mission to enter orbit around a second object, the asteroid 1 Ceres next year in April 2015. The largest asteroid and the first object of its kind discovered on the first day of the 19th century, Ceres looks to be a fascinating world in its own right. Does it possess water ice? Active geology? Moons of its own? If Dawn’s performance at Vesta was any indication, we’re in for another exhilarating round of space exploration!
And artist’s conception of New Horizons at Pluto. Credit: NASA/JPL/Thierry Lombry.
1. New Horizons at Pluto
An easy No. 1,we finally get our first good look at Pluto in July, as NASA’s New Horizons spacecraft flies less than 14,000 kilometres from the surface of the distant world. Launched in 2006, New Horizons will “thread the needle” between Pluto and Charon in a flurry of activity as it passes by. New Horizons will then turn back as it passes into the shadows of Pluto and Charon and actually view the two worlds as they occult the distant Sun. And from there, New Horizons will head out to explore Kuiper Belt Objects of opportunity.
And these are just the top stories that are slated to be big news in space in 2015. Remember, another Chelyabinsk meteor or the next big comet could drop by at any time… space news can be unpredictable, and its doubtless that 2015 will have lots more surprises in store.
The bright supernova (at tick marks) in the galaxy NGC 4666 photographed on December 24, 2014. Credit: Gregor Krannich
A 14th magnitude supernova discovered in the spiral galaxy NGC 4666 earlier this month has recently brightened to 11th magnitude, making it not only the second brightest supernova of the year, but an easy find in an 8-inch or larger telescope. I made a special trip into the cold this morning for a look and saw it with ease in my 10-inch (25-cm) scope at low power at magnitude 11.9.
Before the Moon taints the dawn sky, you may want to bundle up and have a look, too. The charts below will help you get there.
NGC 4666 is also known as the Superwind Galaxy. Home to vigorous star formation, a combination of supernova explosions and strong winds from massive stars in the starburst region drives a vast outflow of gas from the galaxy into space, called a “superwind”. Credit: ESO/J. Dietrich
With the temporary name ASASSN-14lp, this Type Ia supernova was snatched up by the catchy-titled “Assassin Project”, short for Automated Sky Survey for SuperNovae (ASAS-SN)on December 9th. Only 80 million light years from Earth, NGC 4666 is a relatively nearby spiral galaxy famous enough to earn a nickname.
Hot, X-ray emitting gas in NGC 4666 billows around the main galaxy as a superwind seen here as outflows on either side of the optical image. Photo taken with the XMM-Newton telescope. Credit: M. Ehle and ESO
Called the Superwind Galaxy, it’s home to waves of intense star formation thought to be caused by gravitational interactions between it and its neighboring galaxies, including NGC 4668, visible in the lower left corner of the photo above.
Supernovae also play a part in powering the wind which emerges from the galaxy’s central regions like pseudopods on an amoeba. X-ray and radio light show the outflows best. How fitting that a bright supernova should happen to appear at this time. Seeing one of the key players behind the superwind with our own eyes gives us a visceral feel for the nature of its home galaxy.
“Big picture” map showing the location of the galaxy NGC 4666 in Virgo not far from Porrima. The view faces south shortly before the start of dawn in early January. Source: Stellarium
Spectra taken of ASASSN-14lp show it to be a Type Ia object involving the explosive burning of a white dwarf star in a binary system. The Earth-size dwarf packs the gravitational might of a sun-size star and pulls hydrogen gas from the nearby companion down to its surface. Slowly, the dwarf gets heavier and more massive.
When it attains a mass 1.4 times that of the sun, it can no longer support itself. The star suddenly collapses, heats to incredible temperatures and burns up explosively in a runaway fusion reaction. Bang! A supernova.
Detailed map with stars to about magnitude 10. The galaxy is just a little more than a degree northeast of Porrima (Gamma Virginis). Source: Stellarium
Here are a couple maps to help you find the new object. Fortunately, it’s high in the sky just before the start of dawn in the “Y” of Virgo only a degree or so from the 3rd magnitude double star Porrima, also known as Gamma Virginis. Have at it and let us know if you spot the latest superwind-maker.
For more photos and magnitude updates, check out Dave Bishop’s page on the supernova. You can also print a chart with comparison magnitudes by clicking over to the AAVSOand typing in ASASSN-14lp in the “name” box.
A raw shot from the front hazcam of NASA's Opportunity rover taken on Sol 3757, on Aug. 19, 2014. Credit: NASA/JPL-Caltech
Feel like visiting a dwarf planet today? How about a comet or the planet Mars? Luckily for us, there are sentinels across the Solar System bringing us incredible images, allowing us to browse the photos and follow in the footsteps of these machines. And yes, there are even a few lucky humans taking pictures above Earth as well.
Below — not necessarily in any order — are some of the best space photos of 2014. You’ll catch glimpses of Pluto and Ceres (big destinations of 2015) and of course Comet 67P/Churyumov–Gerasimenko (for a mission that began close-up operations in 2014 and will continue next year.) Enjoy!
The Philae that could! The lander photographed during its descent by Rosetta. Credit: ESA/Rosetta/MPS for Rosetta Team/The Aurora Borealis seen from the International Space Station on June 28, 2014, taken by astronaut Reid Wiseman. Credit: Reid Wiseman/NASA.NASA’s Mars Curiosity Rover captures a selfie to mark a full Martian year — 687 Earth days — spent exploring the Red Planet. Curiosity Self-Portrait was taken at the ‘Windjana’ Drilling Site in April and May 2014 using the Mars Hand Lens Imager (MAHLI) camera at the end of the roboic arm. Credit: NASA/JPL-Caltech/MSSSThis global map of Dione, a moon of Saturn, shows dark red in the trailing hemisphere, which is due to radiation and charged particles from Saturn’s intense magnetic environment. Credit: NASA/JPL/Space Science InstituteComet Siding Spring shines in ultraviolet in this image obtained by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. Credit: Laboratory for Atmospheric and Space Physics/University of Colorado; NASAThis “movie” of Pluto and its largest moon, Charon b yNASA’s New Horizons spacecraft taken in July 2014 clearly shows that the barycenter -center of mass of the two bodies – resides outside (between) both bodies. The 12 images that make up the movie were taken by the spacecraft’s best telescopic camera – the Long Range Reconnaissance Imager (LORRI) – at distances ranging from about 267 million to 262 million miles (429 million to 422 million kilometers). Charon is orbiting approximately 11,200 miles (about 18,000 kilometers) above Pluto’s surface. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)The Mars Reconnaissance Orbiter took this image of a “circular feature” estimated to be 1.2 miles (2 kilometers) in diameter. Picture released in December 2014. Credit: NASA/JPL-Caltech/University of ArizonaJets of gas and dust are seen escaping comet 67P/C-G on September 26 in this four-image mosaic. Click to enlarge. Credit: ESA/Rosetta/NAVCAMCeres as seen from the Earth-based Hubble Space Telescope in 2004 (left) and with the Dawn spacecraft in 2014 as it approached the dwarf planet. Hubble Credit: NASA, ESA, J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI). Dawn Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. Photo Combination: Elizabeth Howell
Don't fear the moonlight... Credit and copyright: John Chumack.
Quick… what’s the only major meteor shower named after a defunct constellation? If you said the January Quadrantids, you’d be correct, as this often elusive but abrupt meteor shower is set to peak this coming weekend early in 2015.
And we do mean early, as in the night of January 3rd going into the morning of January 4th. This is a bonus, as early January means long dark nights for northern hemisphere observers. But the 2015 Quadrantids also has two strikes going against them however: first, the Moon reaches Full just a day later on January 5th, and second, January also means higher than average prospects for cloud cover (and of course, frigid temps!) for North American observers.
The rising radiant of the Quads on the morning of January 4th at 3AM local. Note that the Moon and Jupiter are on the scene as well. Created using Starry Night Education software.
Don’t despair, however. In meteor shower observing as in hockey, you miss 100% of the shots that you don’t take.
Sorry for the sports analogy. The radiant for the Quadrantids is located in the modern day constellation of Draco near the Hercules-Boötes border at a right ascension 15 hours, 18 minutes and declination +49.5 degrees north. This puts it very near the +3.3 magnitude star Iota Draconis (Edasich).
The orientation of the Earth’s shadow at the predicted peak of the Quads on January 4th, 2:00 UT. Credit: Orbitron.
In 2015, bets are on for the Quadrantids to peak centered on 2:00 UT January 4th (9:00 PM EST on the 3rd), favoring northern Europe pre-dawn. The duration for the Quadrantids is short lived, with an elevated rate approaching 100 per hour lasting only six hours in duration. Keep in mind, of course, that it’ll be worth starting your vigil on Saturday morning January 3rd in the event that the “Quads” kick off early! I definitely wouldn’t pass up on an early clear morning on the 3rd, just in case skies are overcast on the morning of the 4th…
Due to their high northern radiant, the Quadrantids are best from high northern latitudes and virtually invisible down south of the equator. Keep in mind that several other meteor showers are active in early January, and you may just spy a lingering late season Geminid or Ursid ‘photobomber’ as well among the background sporadics.
Moonset on the morning of the 4th occurs around 6 AM local, giving observers a slim one hour moonless window as dawn approaches. Blocking the Moon out behind a building or hill when selecting your observing site will aid you in your Quadrantid quest.
The approximate realm of the “Mural Quadrant” overlaid on modern day constellations. Credit Stellarium.
Antonio Brucalassi made the first historical reference to the Quadrantids, noting that “the atmosphere was traversed by… falling stars” on the morning of January 2nd, 1825. It’s interesting to note that the modern day peak for the Quads has now drifted a few days to the fourth, due mostly to the leap year-induced vagaries of our Gregorian calendar. The early January meteor shower was noted throughout the 19th century, and managed to grab its name from the trendy 19th century constellation of Quadrans Muralis, or the Mural Quadrant. Hey, we’re lucky that other also-rans, such as Lumbricus the ‘Earthworm’ and Officina Typograhica the ‘Printing Office’ fell to the wayside when the International Astronomical Union formalized the modern 88 constellations in 1922. Today, we know that the Quadrantids come from 2003 EH1, which is thought to be an extinct comet now trapped in the inner solar system on a high inclination, 5.5 year orbit. Could 2003 EH1 be related to the Great Comet of 1490, as some suggest? The enigmatic object reached perihelion in March of 2014, another plus in the positive column for the 2015 Quads.
What the heck is a Mural Quadrant? Like everything he did, Tycho Brahe super-sized his quadrant, depicted here. Credit: Wikimedia Commons.
Previous years for the Quadrantids have yielded the following Zenithal Hourly Rate (ZHR) maximums as per the International Meteor Organization:
2011= 90
2012= 83
2013= 137
2014= +200
The Quadrantid meteor stream has certainly undergone alterations over the years as a result of encounters with the planet Jupiter, and researchers have suggested that the shower may go the way of the 19th century Andromedids and become extinct entirely in the centuries to come.
Don’t let cold weather deter you, though be sure to bundle up, pour a hot toddy (or tea or coffee, as alcohol impacts the night vision) and keep a spare set of batteries in a warm pocket for that DSLR camera, as cold temps can kill battery packs quicker than you can say Custos Messium, the Harvest Keeper.
And though it may be teeth-chatteringly cold where you live this weekend, we actually reach our closest point to the Sun this Sunday, as Earth reaches perihelion on January 4th at around 8:00 UT, just 5 hours after the Quads are expected to peak. We’re just over 147 million kilometres from the Sun at perihelion, a 5 million kilometre difference from aphelion in July. Be thankful we live on a planet with a relatively circular orbit. Only Venus and Neptune beat us out in the true roundness department!
…and no, you CAN’T defy gravity around perihelion, despite the current ill conceived rumor going ‘round ye ole net…
And as a consolation prize to southern hemisphere observers, the International Space Station reaches a period of full illumination and makes multiple visible passes starting December 30th until January 3rd. This happens near every solstice, with the December season favoring the southern hemisphere, and June favoring the northern.
A 2003 south bound Quad nabbed from Cabo Rojo, Puerto Rico (Yes, that’s the Southern Cross!) Credit and Copyright: Frankie Lucena.
So don’t let the relatively bad prospects for the 2015 Quadrantids deter you: be vigilant, report those meteor counts to the IMO, send those meteor pics in to Universe Today and tweet those Quads to #Meteorwatch. Let’s “party like it’s 1899,” and get the namesake of an archaic and antiquated constellation trending!
