Radar image of rows of dunes on Titan. Credit: NASA/JPL-Caltech
Looking like the flowing designs carved by a Zen gardener’s rake, long parallel dunes of hydrocarbon sand stretch across the surface of Saturn’s moon Titan. The image above, acquired by Cassini in July 2013, reveals these intriguing and remarkably Earthlike landforms in unprecedented detail via radar, which can easily pierce through Titan’s thick clouds.
I’m feeling a little more enlightened already.
Although it piles into dunes like sand does here, Titan’s sand is not the same as what you’d find on a beach here on Earth. According to an ESA “Space in Images” article:
While our sand is composed of silicates, the ‘sand’ of these alien dunes is formed from grains of organic materials about the same size as particles of our beach sand. The small size and smoothness of these grains means that the flowing lines carved into the dunes show up as dark to the human eye.
Titan’s surface is almost completely hidden from view by its thick orange “smog” (NASA/JPL-Caltech/SSI. Composite by J. Major)
Radar imaging, although capable of seeing through Titan’s opaque orange atmosphere, doesn’t capture visible-light images. Instead it’s sensitive to the varying textures of a landscape as they reflect microwaves; the smoother an object or an area is the darker it appears to radar, while irregular, rugged terrain shows up radar-bright.
The pixelated “seam” cutting horizontally across the center is the result of image artifacting.
An artists' conception of the X-37B in Earth orbit. Credit: The U.S. Air Force.
A secretive mission will pass a quiet milestone at the end of this month when the U.S. Air Force’s unmanned spaceplane the X-37B surpasses 500 days in space.
Launched atop an Atlas V rocket flying in a 401 configuration from Cape Canaveral Florida after several delays on December 11th, 2012 on OTV-3, the X-37B has already surpassed its own record of 469 days in space set on OTV-2. Said milestone was crossed last month. If the current mission stays in space until April 25th of this year, it will have surpassed 500 days in space.
Two X-37Bs were built for the USAF, and the first test mission flew in 2010. NASA performed drop glide tests with an early variant of the X-37A in 2005 and 2006, and DARPA is thought to be a primary customer for the program as well.
Measuring just 8.8 metres in length, the X-37B is tiny compared to its more famous spaceplane cousin the U.S. Space Shuttle. The X-37B has a maximum weight at liftoff of 4,990 kilograms and features a payload bay 2.1 by 1.2 metres in size.
The spacecraft itself is solar powered, as it unfurls a panel — as depicted in many artists’ conceptions — once it’s in orbit. Of course, its mission profile is classified, and the X-37B could land unannounced at any time. The previous landings occurred at Vandenberg Air Force Base in California and were only announced shortly thereafter.
Not only is this the longest continuous mission for any spaceplane, but the ATV-3 is also the smallest, lightest and only the second spaceplane to land autonomously, the first being the Russian space shuttle Buran that flew one mission and landed after one orbit at the Baikonur Cosmodrome on November 15th, 1988.
The X-37B awaiting encapsulation for launch. Credit: U.S. Air Force.
The idea of a reusable spaceplane has been around since the dawn of the Space Age. The U.S. Space Shuttle program was the most high profile of these, having flown 135 missions from 1981 to 2011. But even the space shuttle launch system wasn’t fully reusable, expending its large orange external fuel tank after every mission and requiring extensive refurbishment for the solid rocket motors and orbiter after each and every flight. The Soviets abandoned Buran in 1988, and other examples of spaceplanes such as North American’s X-15 surpassed the 100 kilometre in altitude Kármán line marking the boundary to space, but were suborbital only. And this year, customers may get a chance to make similar suborbital hops into space aboard Virgin Galactic’s SpaceShipTwo spaceplane at $250,000 dollars a ticket.
But the most ambitious design for a true spaceplane was conceived in the 1960’s: Boeing’s X-20 Dyna-Soar, which was never built.
Classified satellites such as the X-37B are part of a longstanding and fascinating “secret space race” that has paralleled and shadowed the more well known space programs of various nations over the decades. These include the Corona program which ran from 1959 to 1972 and was only declassified in 1995, and satellites such as Lacrosse 5, which is notorious among satellite sleuths for the orbital “vanishing act” it sometimes pulls.
And speaking of which, you can track the X-37B from your backyard, tonight. Ground spotters first pegged its position in low Earth orbit during OTV-1 on May 22nd 2010, and the spacecraft currently sits in a 392 x 296 kilometre (nearly circular) orbit in an 43.5 degree inclination, making it visible from latitudes 55 degrees north to south. On a favorable overhead pass, the X-37B is easily visible shining at greater than magnitude +1. OTV-3’s NORAD ID designation is 39025 or 2012-071A, and although – like most classified payloads – it’s not available to the public on Space-Track, Heavens-Above does list upcoming sighting opportunities. Be sure to start watching a bit early, as the X-37B has been known to maneuver a bit in its orbit on occasion.
Of course, just what the X-37B is doing in orbit is anybody’s guess. Speculation is that it’s serving as a test bed for new technologies. Certainly, the ability to place interchangeable payloads in orbit is immediately apparent. It’s also worth noting that the X-37B makes multiple daily passes on its northward apex over North Korea and China. There’s also been speculation that the X-37B was designed to keep tabs on the Chinese space station Tiangong-1, although this can easily be refuted as they both lie in different orbits. There’s no word as to what’s to become of Tiangong-1, though China had said it was set to deorbit the station at the end of 2013, and it is still in space.
Looking ahead into the future, there has been talk about a larger crewed variant known as the X-37C, which will undoubtedly fly much shorter missions. For now, we can watch and wonder what it’s up to, as the X-37B glides silently overhead. Perhaps one day, its mission will declassified, and its tale can be told.
-For more info sat-tracking, check out our how-to post and also read about the fascinating true role that amateurs played during the Cold War and Operation Moonwatch.
A cosmic ray hit on a camera on the Curiosity rover produced what looks like a 'light' on Mars. Credit: NASA/JPL
Thanks to everyone who has emailed, Tweeted and texted me about the “artificial bright light” seen on Mars. And I’m so sorry to disappoint all the folks who were hoping for aliens, but what you see above is just an image artifact due to a cosmic ray hitting the right-side navigation camera on the Curiosity rover.
If you do a little research, you can see that the light is not in the left-Navcam image that was taken at the exact same moment (see that image below). Several imaging experts agree this is a cosmic ray hit, and the fact that it’s in one ‘eye’ but not the other means it’s an imaging artifact and not something in the terrain on Mars shooting out a beam of light.
Update: JPL imaging specialists with the MSL mission have now weighed in on these images. “In the thousands of images we’ve received from Curiosity, we see ones with bright spots nearly every week,” said Justin Maki in a press release from JPL. Maki is leader of the team that built and operates the Navigation Camera. “These can be caused by cosmic-ray hits or sunlight glinting from rock surfaces, as the most likely explanations.”
If the bright spots in the April 2 and April 3 images are from a glinting rock, the directions of the spots from the rover suggest the rock could be on a ridge about 175 yards (160 meters) from the rover’s April 3 location.
The bright spots appear in images from the right-eye camera of the stereo Navcam, but not in images taken within one second of those by the left-eye camera. Maki said, “Normally we can quickly identify the likely source of a bright spot in an image based on whether or not it occurs in both images of a stereo pair. In this case, it’s not as straightforward because of a blocked view from the second camera on the first day.”
The left-Navcam image from April 4, 2014 shows no ‘light.’ Credit: NASA/JPL.
Cosmic ray hits happen frequently on spacecraft that don’t have the benefit of being in Earth’s thick atmosphere. And frequently, people seem to get excited about what shows up in imagery that have been affected. For example, one guy thought there was a huge base on Mars based on some he saw on Google Mars.
Getting hit by a cosmic ray can have some serious consequences for a spacecraft — sometimes it can put them into what’s called “safe mode” where only basic functions operate, or other times it can mess up data (like what happened with Voyager 2 in 2010 where the data sent back to Earth was unreadable). Usually, engineers are able to fix the problem and get the spacecraft back in working order.
Cosmic rays can even show up in imagery taken by astronauts on the International Space Station, like this one by astronaut Don Pettitt in 2012:
A cosmic ray hit on a camera appears as a segmented line in the image. Credit: NASA/Don Pettit..
Astronauts also report seeing flashes — even with their eyes closed — whenever cosmic rays zip through their eyeballs. You can read more about that here.
And so far, none of these blips, lights or flashes seen on space imagery has ever been “because aliens.”
Additionally, if you want to see bright lights associated with Mars, all you have to do is look up in the sky at night and see Mars shining brilliantly in the sky right now. Mars is in opposition, where it is closest to the Earth, and the “official” closest moment happens today, April 8th! Find out more about how to see it or watch different webcasts taking place today at our previous article here.
Mars, the Full Moon and Spica rising in the east on April 14th. Created using Stellarium.
And for those of you who think we shouldn’t give “air time” to nutty claims like lights on Mars, it is our policy to address and debunk such claims (for example, see our article debunking the latest end of the world claim) in order to make sure the real story and good doses of reality are out there, too, and available to people who are looking for the real story.
omet C/2014 E2 Jacques on April 1, 2014. Credit and copyright: Damian Peach.
We’ve got a hot comet on our hands. Comet Jacques barely cracked magnitude +11 at the time of its March 13 discovery, but just three weeks later, amateur astronomers have already spotted it in large binoculars at magnitude +9.5. Expert comet observer Michael Mattiazzo, who maintains the Southern Comets Homepage,predicts that if Comet Jacques continues its rapid rise in brightness, it might become faintly visible with the naked eye by July.
Discovery images of Comet Jacques by the SONEAR team show a small, condensed object with a short, faint tail. Credit: SONEAR
The comet’s currently inching across the southern constellation Antlia headed toward Puppis and Monoceros later this month. Observers describe it as “very diffuse” with a large, dim coma and moderately compact core. Photos show a short tail pointing east-northeast. This past weekend C/2014 E2 passed closest to the Earth at 89.3 million miles (144 million km) on its way to perihelion on July 2.
Comet Jacques photographed on April 3, 2014 when it was near two faint galaxies. Credit: Efrain Morales
Right now, observers in southern latitudes have the viewing advantage. As seen from South America and Australia, Comet Jacques floats high in the southwestern sky at nightfall. Observers in mid-northern latitudes can see it too, but have to set their sights lower. A week ago I tried tracking down this newcomer with a 37-cm (15-inch) Dobsonian reflector around 9 o’clock. With Jacques only 14 degrees high at the time I had to kneel beside the telescope to see into the eyepiece. Try as I might, I suspected only a fuzzy patch at best. Light pollution and low altitude were partly to blame, but Jacques’ diffuse appearance may have contributed to the uncertain observation. Other mid-northern latitude observers may have shared my sore kneecap experience in similar attempts.
Map dated April 16 showing Comet Jacques’ path from mid-April to mid-May. Positions are marked every 5 days with stars down to magnitude +8. Click to enlarge. Created with Chris Mariott’s SkyMap software
But that will soon change. C/2014 E2 continues to increase in altitude throughout the month, offering easier viewing as soon as mid-month. April 16 through early May the moon will be gone from the sky and provide a needed dark time slot for viewing the comet before it’s lost in evening twilight. Comet Jacques will likely be brighter than magnitude 9 as it slides from Puppis into Monoceros.
Find a place with a dark sky to the southwest and start looking at the end of evening twilight when the comet is highest. The map shows stars in reverse making it easier to use in crowded star fields.
Comet Jacques is approaching the sun from beneath (south of) the plane of the planets indicated by the dark blue curve of its orbit. It crosses northward later this spring (Iight blue). Credit: NASA/JPL
By mid-July, Comet Jacques will have passed perihelion 61 million miles (98 million km) from the sun and transition into the morning sky as it rapidly swings northward across Taurus, Auriga and Perseus. Though the comet will be half again as far from Earth as it is today, it’s expected to become considerably brighter and more condensed after a good “roasting” by the sun.
The participants of the DSN NASA Social gathered in front of the DSS-14 70-meter antenna at Goldstone, April 2, 2014.
When you’re talking to spacecraft billions of miles away, you need a powerful voice. And when you’re listening for their faint replies from those same staggering distances, you need an even bigger set of ears. Fortunately, NASA’s Deep Space Network has both — and last week I had the chance to see some of them up close and in person as one of the lucky participants in a NASA Social! Here’s my overview of what happened on those two exciting days.
(And if this doesn’t make you want to apply for the next Social, I don’t know what will.)
The main building at Jet Propulsion Laboratory in Pasadena (J. Major)
The event began on April 1 (no foolin’) at NASA’s Jet Propulsion Laboratory in Pasadena. Nestled at the feet of steep pine-covered hills northeast of Los Angeles, JPL’s campus is absolutely gorgeous… not quite the location you might imagine for the birthplace of robotic interplanetary explorers! But for over 55 years JPL has been developing some of the world’s most advanced spacecraft, from the Ranger probes which took NASA’s first close-up images of the Moon to the twin Voyagers that toured the Solar System’s outer planets, countless Earth-observing satellites that have revolutionized our ability to monitor global weather, and all of the rovers that have been our first “wheels on the ground” on Mars.
Of course, none of those missions would have been possible if we didn’t have the ability to communicate with the spacecraft. That’s why NASA’s Deep Space Network is such an integral — even if not oft-publicized — part of each and every mission… and has been for 50 years.
In fact, that was the purpose of this Social event which gathered together 50 space fans from across the U.S. — to celebrate the achievements of the DSN with an eye-opening tour of both JPL and the DSN’s Goldstone facility with its flagship 70-meter dish, located amongst the rocky scrub-covered hills in the middle of a military base in California’s Mojave desert.
For many participants — including myself — it was the first time visiting JPL. I can’t tell you how many times I’ve written about the news that comes out of it, featured its amazing images, and typed the credit line “NASA/JPL-Caltech” in the caption of a picture, so for me it was incredible to actually be there in person. Just driving through the front gate at JPL, with “Welcome To Our Universe” mounted over the window of the guard station, was mind-blowing!
Setting up camp in Mission Control (J. Major)This 16-inch-wide plaque is set into the floor of the “dark room” at JPL Mission Control, covered by a pane of clear acrylic. (J. Major)
From the Visitor’s Center we were gathered into groups and taken into the heart of JPL to get a look at the Mission Control room, aka the “center of the universe.” This is where all the data from ongoing space exploration missions arrives (after being collected by the Deep Space Network, of course.) And we didn’t just get to see Mission Control — we actually set up our computers there and got to take our seats at the very same desks that top JPL and NASA engineers and scientists used during the MSL landing in August 2012! In fact we were treated to a replay of Curiosity’s landing on the screens against the wall that first displayed the rover’s images of Gale Crater. The whole experience was a bit surreal — I vividly recall watching it live, and there we were in the same room as if it were happening all over again! (We even got to re-enact the celebration of the touchdown announcement as our group photo.)
After several presentations and Q&A sessions with NASA mission engineers — recorded live for NASA TV — we all embarked on a tour of JPL’s rock-strewn “Mars Yard” where a stunt double of Curiosity, named “Maggie,” resides in a super high-tech garage. Maggie helps engineers determine what Curiosity can and can’t do on Mars… much more safely than actually having the “real” rover attempt itself.
Watch the NASA TV coverage from Mission Control below:
The group then got the chance to see an actual spacecraft being built in the Spacecraft Assembly Facility, a huge clean room where engineers were building components of the upcoming SMAP (Soil Moisture Active Passive) satellite. Slated for launch in October, SMAP will take measurements of the planet’s soil moisture in its freeze/thaw states from orbit over a period of three years. As we watched from the windowed viewing platform several “bunny-suited” engineers were busy working on SMAP’s 6-meter reflector. In another six months or so the parts that were scattered around that clean room will be performing science in orbit!
Where space explorers are born: JPL’s Spacecraft Assembly Facility (J. Major)Randii Wessen (left) and Todd Barber (right) demonstrate… well, I’m not sure what they were demonstrating but it was very entertaining! (J. Major)
From there it was off to the JPL museum and some intimate (and highly animated!) discussions about mission technology with project formulator Randii Wessen and propulsion engineer Todd Barber. Afterward I took the opportunity to talk with Todd a bit about his role on the Cassini mission, for which he’s the lead propulsion engineer.
(You all know how much I adore Cassini, so that was a real treat.)
When we got back to Mission Control we had a chance to meet with and have photos taken with JPL’s very own “Mohawk guy” Bobak Ferdowsi, who achieved widespread fame during the internet broadcast landing of Curiosity. I had Bobak sign my toy Curiosity rover, which now has a “BF” on the back of its die-cast RTG. One for the space shelf!
The second half of the Social began early the next day — for me, very early. After getting up at 3:15 a.m. and making a two-hour drive from Pasadena to Barstow in the dark, I and the other participants met up with the Social bus in a park-and-ride lot at 6:00 just as the Sun was beginning to brighten the eastern sky. (Some had stayed overnight in Barstow, while others made the early drive out like I did.) Once the bus filled, we headed north into the Mojave to arrive at NASA’s Deep Space Network Communications Complex at Goldstone, located within the Fort Irwin military training area.
The 70-meter dish at NASA’s DSN complex at Goldstone (J. Major)
The location is rugged and remote — the perfect place to listen for the faint signals from spacecraft trundling across dusty Mars and soaring through the farthest reaches of the Solar System! The nine main DSN antennas at Goldstone are scattered across several square miles of desert, enormous dishes pointed more-or-less directly upward, aiming at the locations of distant spacecraft in order to both receive and transmit data. All of them are huge, but by far the most impressive is the gigantic 70-meter DSS-14 dish that towers above the rest in both height and width.
Recently renovated , the fully-positionable DSS-14 “Mars antenna” dish (so called because of its first mission tracking the Mariner 4 spacecraft in 1965) weighs in at 2.7 million kilograms yet “floats” atop a thin film of oil a quarter of a millimeter thick!
How smoothly does a three-thousand-ton radar dish move? We got to find out — check out the video below:
(Note: as it turned out, DSS-14 wasn’t turning to communicate with anything… the show was just for us!)
Of course, we all spent plenty of time taking pictures of the 70-meter, both inside and out — we were treated to a tour of this and several other dish sites hosted by JPL’s Jeff Osman, a specialist in the DSN antennas and their operations.
(One of us even chose to record the DSS-14 antenna with pencils and paper — watch fellow Social participant Jedediah Dore’s sketch and account of the experience here.)
Jim Erickson, JPL’s Project Manager for the Mars Rovers and MRO, speaks during the 50th Anniversary Event (J. Major)
The highlight of the day at Goldstone was (if not just being there!) was being present for the official celebration of the facility’s 50th anniversary. Featuring speakers from JPL and DSN, as well as many esteemed guests, the event — held indoors because of strong winds outside — commemorated the impact and important contributions of the complex over the past half-century of space exploration. According to speaker Jim Erickson of JPL, “There hasn’t been a time in my career when the DSN wasn’t there for us.”
After that the NASA Social group was invited to take a few moments to mingle with speakers and guests — when else would I have a chance to chat with JPL director Dr. Charles Elachi? — and then we all returned to our own meeting room where refreshments were waiting and a (quite delicious) DSN50 cake was cut and served.
It was truly a fantastic and well-planned event, giving 50 people the chance to see an integral part of our space program that, although it doesn’t usually receive the same kind of exposure that rocket launches and planetary landings enjoy, makes all of it possible.
Here’s to 50 more years of DSN and its long-distance relationship with all of our intrepid space explorers!
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See what communications are currently coming in and going out of the DSN dishes — in Goldstone as well as in Madrid and Canberra — here, and learn more about the history of Goldstone here.
And a big thanks to Courtney O’Connor, Veronica McGregor, John Yembrick, and Stephanie Smith for putting this NASA Social together, Annie Wynn and Shannon Moore for setting up and organizing participant groups on Facebook and Google (which makes offsite planning so much easier), Jeff Osman and Shannon McConnell for the tours of the DSN sites and, of course, everyone at JPL and Goldstone who helped to make the event a wonderful success!
Would you like to be a part of a NASA Social? Find out what events are coming up and how to apply for them here.
A mosaic of the 2003 total lunar eclipse. photos by author.
By now, you may have already heard the latest tale of gloom and doom surrounding the upcoming series of lunar eclipses.
This latest “End of the World of the Week” comes to us in what’s being termed as a “Blood Moon,” and it’s an internet meme that’s elicited enough questions from friends, family and random people on Twitter that it merits addressing from an astronomical perspective.
Like the hysteria surrounding the supposed Mayan prophecy back in 2012 and Comet ISON last year, the purveyors of Blood Moon lunacy offer a pretty mixed and often contradictory bag when it comes down to actually what will occur.
But just like during the Mayan apocalypse nonsense, you didn’t have to tally up just how many Piktuns are in a Baktun to smell a rat. December 21st 2012 came and went, the galactic core roughly aligned with the solstice — just like it does every year — and the end of the world types slithered back into their holes to look for something else produce more dubious YouTube videos about.
Here’s the gist of what’s got some folks wound up about the upcoming cycle of eclipses. The April 15th total lunar eclipse is the first in series of four total eclipses spanning back-to-back years, known as a tetrad. There are eight tetrads in the 21st century: if you observed the set total lunar eclipses back in 2003 and 2004, you saw the first tetrad of the 21st century.
The eclipses in this particular tetrad, however, coincide with the Full Moon marking Passover on April 15th and April 4th and the Jewish observance of Sukkot on October 8th and September 28th. Many then go on to cite the cryptic biblical verse from Revelation 6:12, which states;
“I watched as he opened the sixth seal. There was a great earthquake. The Sun turned black like sackcloth made of goat hair. The whole Moon turned blood red.”
Whoa, some scary allegory, indeed… but does this mean the end of the world is nigh?
I wouldn’t charge that credit card through the roof just yet.
First off, looking at the eclipse tetrads for the 21st century, we see that they’re not really all that rare:
21st century eclipse tetrads:
Eclipse #1
Eclipse #2
Eclipse #3
Eclipse #4
May 16th, 2003
November 9th, 2003
May 4th , 2004
October 28th, 2004
April 15th, 2014*+
October 8th, 2014
April 4th, 2015*+
September 28th, 2015
April 25th, 2032
October 18th, 2032
April 14th, 2033*+
October 8th, 2033
March 25th, 2043*
September 19th, 2043
March 13th, 2044
September 7th, 2044
May 6th, 2050
October 30th, 2050
April 26th, 2051
October 19th, 2051
April 4th, 2061*+
September 29th, 2061
March 25th, 2062*
September 18th, 2062
March 4th, 2072
August 28th, 2072
February 22nd, 2073
August 17th, 2073
March 15th, 2090
September 8th, 2090
March 5th, 2091
August 29th, 2091
*Paschal Full Moon
+Eclipse coincides with Passover
Furthermore, Passover is always marked by a Full Moon, and a lunar eclipse always coincides with a Full Moon by definition, meaning it cannot occur at any other phase. The Jewish calendar is a luni-solar based calendar that attempts to mark the passage of astronomical time via the apparent course that the Sun and the Moon tracks through the sky. The Muslim calendar is an example of a strictly lunar calendar, and our western Gregorian calendar is an example of a straight up solar one. The Full Moon marking Passover often, though not always, coincides with the Paschal Moon heralding Easter. And for that matter, Passover actually starts at sunset the evening prior in 2014 on April 14th. Easter is reckoned as the Sunday after the Full Moon falling after March 21st which is the date the Catholic Church fixes as the vernal equinox, though in this current decade, it falls on March 20th. Easter can therefore fall anywhere from March 22nd to April 25th, and in 2014 falls on the late-ish side, on April 20th.
To achieve synchrony, the Jewish calendar must add what’s known as embolismic or intercalculary months (a second month of Adar) every few years, which in fact it did just last month. Eclipses happen, and sometimes they occur on Passover. It’s rare that they pop up on tetrad cycles, yes, but it’s at best a mathematical curiosity that is a result of our attempt to keep our various calendrical systems in sync with the heavens. It’s interesting to check out the tally of total eclipses versus tetrads over a two millennium span:
Century
Number of Total Lunar Eclipses
Number of Tetrads
Century
Number of Total Lunar Eclipses
Number of Tetrads
11th
62
0
21st
85
8
12th
59
0
22nd
69
4
13th
60
0
23rd
61
0
14th
77
6
24th
60
0
15th
83
4
25th
69
4
16th
77
6
26th
87
8
17th
61
0
27th
79
7
18th
60
0
28th
64
0
19th
62
0
29th
57
0
20th
81
5
30th
63
1
Note that over a five millennium span from 1999 BC to 3000 AD, the max number of eclipse tetrads that any century can have is 8, which occurs this century and last happened in the 9th century AD.
Of course, the visual appearance of a “Blood of the Moon” that’s possibly alluded to in Revelation is a real phenomena that you can see next week from North and South America as the Moon enters into the dark umbra or core of the shadow of the Earth. But this occurs during every total lunar eclipse, and the redness of the Moon is simply due to the scattering of sunlight through the Earth’s atmosphere. Incidentally, this redness can vary considerably due to the amount of dust, ash, and particulate aerosols aloft in the Earth’s atmosphere, resulting in anything from a bright cherry red eclipse during totality to an eclipsed Moon almost disappearing from view altogether… but it’s well understood by science and not at all supernatural.
The changing colors of a lunar eclipse: a mosaic of four eclipses. Photos by author.
Curiously, the Revelation passage could be read to mean a total solar eclipse as well, though both can never happen on the same day. Lunar and solar eclipses occur in pairs two weeks apart at Full and New Moon phases when the nodes of the Moon’s ecliptic crossing comes into alignment with the Sun — known as a syzygy, an ultimate triple word score in Scrabble, by the way — and this eclipse season sees a non-central annular eclipse following the April 15th eclipse on April 29th.
And yes, earthquakes, wars, disease, relationship breakups and lost car keys are on tap to occur in 2014 and 2015… just like during any other year. Lunar eclipses marked the fall of Constantinople in 1453 and the World Series victory of the Red Sox in 2004, but they’re far from rare. We humans love to see patterns, and sometimes this habit works against us, making us see them where none exists. This is simply a case of the gambler’s fallacy, counting the hits at the cost of the misses. We could just as easily make a case that the upcoming eclipse tetrad of April 15th, October 8th, April 4th and September 28th marks US Tax Day, Croatian Independence Day, The Feast of Benedict of the Moor & — Michael Scott take note — International World Rabies Day… perhaps the final 2015 eclipse should be known as a “Rabies Moon?”
So, what’s the harm in believing in a little gloom and doom? The harm in believing the world ends tomorrow comes when we fail to plan for still being here the day after. The harm comes when something like the Heavens Gate mass suicide goes down. We are indeed linked to the universe, but not in the mundane and trivial way that astrologers and doomsdayers would have you believe. Science shows us where we came from and where we might be headed. We’ve already fielded queries from folks asking if it’s safe (!) to stare at the Blood Moon during the eclipse, and the answer is yes… don’t give in to superstition and miss out on this spectacular show of nature because of some internet nonsense.
The upcoming lunar eclipse next week won’t mean the end of the world for anyone, except, perhaps, NASA’s LADEE spacecraft… be sure not to miss it!
Everything dies, including our technology. But when we’ve hurtled a few thousands pounds of robotic instrumentation to another planet, it gets a little difficult to shut it down and clean up. What do we do when a mission has reached the end of its useful life?
Artist's conception of how the Baryon Oscillation Spectroscopic Survey uses quasars to make measurements. The light these objects sends out gets absorbed by gas in between the receiver and the source. The gas is then "imprinted wiht a subtle ring-like pattern of known physical scale", the Sloan Digital Sky Survey stated. Credit: Zosia Rostomian (Lawrence Berkeley National Laboratory) and Andreu Font-Ribera (BOSS Lyman-alpha team, Berkeley Lab.)
For those who saw the Cosmos episode on William Herschel describing telescopes as time machines, here is a clear example of that. By examining 140,000 objects called quasars (galaxies with an active black hole at their centers), astronomers have charted the expansion rate of the universe — not now, but 10.8 billion years ago.
This is the most precise measurement ever of the universe’s expansion rate at any point in time, the science teams said, with the calculation showing the universe was expanding by 1% every 44 million years at that time. (That figure is to 2% precision, the researchers added.)
“If we look back to the Universe when galaxies were three times closer together than they are today, we’d see that a pair of galaxies separated by a million light-years would be drifting apart at a speed of 68 kilometers per second as the Universe expands,” stated Andreu Font-Ribera of the Lawrence Berkeley National Laboratory, who led one of the two analyses.
The researchers used a telescope called the Sloan Digital Sky Survey, a 2.5-meter telescope at Apache Point Observatory in New Mexico. The discovery was made during Sloan’s Baryon Oscillation Spectroscopic Survey, or BOSS, whose aim has been to figure out the expansion and acceleration of the universe.
The accelerating, expanding Universe. Credit: NASA/WMAP
“BOSS determines the expansion rate at a given time in the Universe by measuring the size of baryon acoustic oscillations (BAO), a signature imprinted in the way matter is distributed, resulting from sound waves in the early Universe,” the Sloan Digital Sky Survey stated. “This imprint is visible in the distribution of galaxies, quasars, and intergalactic hydrogen throughout the cosmos.”
Font-Ribera and his collaborators examined how quasars are distributed compared to hydrogen gas to calculate distance. The other analysis, led by Timothée Delubac (Centre de Saclay, France), examined the hydrogen gas to see patterns and measure mass distribution.
You can read more about Font-Ribera’s team’s research in preprint version on Arxiv. Delubac’s research does not appear to be available online, but the title is “Baryon Acoustic Oscillations in the Ly-alpha forest of BOSS DR11 quasars” and it has been submitted to Astronomy & Astrophysics.
It feels like you just can’t get away from clingy gravity. Even separated by distances of hundreds of millions of light years, gravity is reaching out to all of us. Is there a place you could go to get away from gravity entirely?
Fortunately for our space intolerant tissues and terrible oxygen dependency withdrawal symptoms, gravity binds us to our sweet, cozy home with breathable air, the Earth. Its collective mass is trying to accelerate you towards its center, that way, at 9.8 meters per second squared. But the Earth isn’t the only one looking to cuddle.
You’re also being pulled at by the Moon, and if it weren’t for the Earth here, that pull could hurl you far off into deep space, or crash you into its cold dusty surface. In fact, as the Moon passes overhead, you’re being imperceptibly tugged upwards. This possessive tug o war isn’t just between the moon, and the earth fighting over you like an older brother keeping a small doll out of reach a younger sibling.
The Sun is also in on this shenanigan. Gravity from there is pulling at you from a distance of 150 million km. Well, aren’t we popular. So how far would you have to go to escape this gravitational custody battle completely?
Even At 2.5 million light years distance, gravity is still reaching out and being a clingy creeper. The Milky Way and Andromeda are pulling towards each other. The gravity between these two bodies is strong enough to overcome the expansion of the universe. Which will result in a galactic smash-up derby a few billion years from now.
There’s no end to it. Gravity appears to be madly greedy and long armed. Members of the Virgo Super cluster are connected to each other, and they’re dozens of millions of light-years apart. Objects in the Pisces-Cetus Super cluster complex are even connected to each other by our invisible and obnoxiously possessive friend. And they are hundreds of millions of light years apart…
In fact, you’re so popular that you are gravitationally pulled towards even most distant object in the observable Universe. And they, in turn, are linked to you. As a result, without the outward expansion and acceleration of the Universe, everything would fall inward to a common center of gravity. Newton thought that gravity was instantaneous and if the Sun disappeared, the Earth would immediately fly away. Einstein realized that gravity is distortions of spacetime caused by mass. And as it turns out, gravity moves at the speed of light.
Artist’s impression of gravitational waves. Image credit: NASA
If the Sun disappeared, Earth would continue to follow the curved spacetime distortion for 8 whole minutes. Interactions between massive objects, like when black holes collide, cause ripples in spacetime called gravitational waves. As a gravitational wave passes through, you get warped in spacetime, like a wave in the water. The amount is so slight we’ve never seen them directly. However, the decay of pulsar orbits have shown them indirectly.
The ground-based LIGO experiment might someday detect a gravitational wave, but there’s been no luck so far. The Space-based LISA experiment should detect gravitational waves with more precision. The first version will launch in 2015, but the real experiment probably won’t be operational until 2030.
Everybody wants a piece, and I don’t know about you, I just want to be left alone. Gravity’s is reach is amazingly far. It’s everywhere, all the time, and it’s having none of that. What do you think? If you had the power to remove yourself from Gravity’s pull, what would you do? Tell us in the comments below.
Separation of the third stage during the Sentinel-1 launch in April 2014. Credit: Arianespace/European Space Agency /Roscosmos (YouTube/screenshot)
Imagine clinging on to the side of a rocket, somehow able to hang on despite the high speeds and diminishing oxygen. Looking down, this is what you’ll see — the view in the video above. This incredible sequence shows Sentinel-1a during its initial climb to orbit last week and, if you wait long enough, you can even see the separation of the third stage.
“Arianespace’s successful Soyuz Flight VS07 — which deployed Sentinel-1A to Sun-synchronous orbit — gave the world a front-row seat in space,” the company stated on YouTube. “Cameras mounted on the Soyuz’ Fregat upper stage captured the spectacular footage … as Sentinel-1A was separated at approximately 700 km [434 miles] above the Earth to commence its life in orbit.”
Sentinel-1a is the first of a series of environmental monitoring satellites overseen by the European Space Agency, a set that promises views of the Earth in high-definition.
