The sleek and sexy-looking GOCE spacecraft has been mapping Earth’s gravity for over four years, but soon its xenon fuel will run out and the satellite will end up re-entering our atmosphere. But no one can say for sure when or where the 1-ton satellite will fall.
The Gravity field and steady-state Ocean Circulation Explorer has been orbiting Earth at super-low orbits, mapping out variations in Earth’s gravity with extreme detail. Launched in March 2009, the GOCE spacecraft was designed to fly low and has spent most of its mission roughly 500 km below most other Earth-observing missions, at an altitude of 255 km (158 miles), but has recently been at the lowest altitude of any research satellite at 224 km (139 miles).
With its sleek, aerodynamic design, some have called it the ‘Ferrari of space,’ but we’ve just called it sexy, like a satellite straight out of a James Bond movie.
And the satellite has delivered with unique results of Earth’s ‘geoid’ — precise measurements of ocean circulation, sea-level change and ice dynamics, greatly improving our knowledge and understanding of the Earth’s internal structure. The mission has also been studying air density and wind in space. Its data also produced the first global high-resolution map of the boundary between Earth’s crust and mantle, called the Mohorovicic, or “Moho” discontinuity.
Mission managers predict that in mid-October 2013 the spacecraft will run out of fuel and the satellite will begin its descent towards Earth. There will be no remaining fuel to guide its re-entry, and while most of GOCE is predicted to disintegrate in the atmosphere, several parts might reach Earth’s surface. Experts predict as much as 25% of the spacecraft will survive reentry, as many parts are made of advanced materials, such as carbon-carbon composites.
But when and where these parts might land cannot yet be predicted, ESA says.
As the re-entry time nears, better predictions will be made. Re-entry is expected to happen about three weeks after the fuel is depleted.
ESA says that taking into account that two thirds of Earth are covered by oceans and vast areas are thinly populated, the danger to life or property is very low.
Recently, other larger satellites have made uncontrolled re-entries, such as NASA’s 6-ton UARS spacecraft and Germany’s 2.4-ton ROSAT in 2011 and the 13-ton failed Russian Mars probe, Phobos-Grunt in 2012.
About 40 tons of human-made space debris reach the ground per year, but the spread and size mean the risk of an individual being struck is lower than being hit by a meteorite.
An international campaign will be monitoring the descent, involving the Inter-Agency Space Debris Coordination Committee. The situation is being continuously watched by ESA’s Space Debris Office, which will issue re-entry predictions and risk assessments.
ESA says they will keep the relevant safety authorities permanently updated.
Have you heard there’s a giant planet in the Solar System headed straight towards Earth?
At some point in the next few months or years, this thing is going to crash into Earth or flip our poles, or push us out of our orbit, or some other horrible civilization destroying disaster.
Are these rumours true?
Is there a Planet X on a collision course with Earth?
Unlike some of the answers science gives us, where we need to give a vague and nuanced answers, like yes AND no, or Maybe, well, it depends…
I’m glad to give a straight answer: No.
Any large object moving towards the inner Solar System would be one of the brightest objects in the night sky. It would mess up the orbits of the other planets and asteroids that astronomers carefully observe every night.
There are millions of amateur astronomers taking high quality images of the night sky. If something was out there, they’d see it.
These rumours have been popping up on the internet for more than a decade now, and I’m sure we’ll still be debunking them decades from now.
What people are calling Planet X, or Nibiru, or Wormwood, or whatever doesn’t exist. But is it possible that there are large, undiscovered objects out in the furthest reaches of Solar System?
Sure.
Astronomers have been searching for Planet X for more than a hundred years. In the 1840s, the French mathematician Urbain Le Verrier calculated that another large planet must be perturbing the orbit of Uranus. He predicted the location where this planet would be, and then German astronomer Johann Gottfried Galle used those coordinates to discover Neptune right where Le Verrier predicted.
The famed astronomer Percival Lowell died searching for the next planet in the Solar System, but he made a few calculations about where it might be found.
A young Clyde Tombaugh with one of his famous homemade telescopes. (Credit : NASA/GSFC).And in 1930, Clyde William Tombaugh successfully discovered Pluto in one of the locations predicted by Lowell.
Astronomers continued searching for additional large objects, but it wasn’t until 2005 that another object the size of Pluto was finally discovered by Mike Brown and his team from Caltech: Eris. Brown and his team also turned up several other large icy objects in the Kuiper Belt; many of which have been designated dwarf planets.
We haven’t discovered any other large objects yet, but there might be clues that they’re out there.
In 2012, the Brazilian astronomer Rodney Gomes calculated the orbits of objects in the Kuiper Belt and found irregularities in the orbits of 6 objects. This suggests that a larger object is further out, tugging at their orbits. It could be a Mars-sized object 8.5 billion km away, or a Neptune-sized object 225 billion km away.
A false-color, visible-light image of Comet ISON taken with Hubble’s Wide Field Camera 3. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)There’s another region at the edge of the Solar System called the Oort Cloud. This is the source of the long-period comets that occasionally visit the inner Solar System. It’s possible that large planets are perturbing the orbits of comets with their gravity, nudging these comets in our direction.
So, feel free to ignore every single scary video and website that says an encounter with Planet X is coming.
And use that time you saved from worrying, and use it to appreciate the amazing discoveries being made in space and astronomy every day.
And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.
Water, ammonia, methanol and carbon dioxide could have come to Earth from cometary sources, according to a new study. Source: Lawrence Livermore National Laboratory
The energy of comets smashing into Earth billions of years ago could have generated life out of the building blocks of life that those extraterrestrial objects brought, according to new experiments published in a peer-reviewed study.
The finding comes after a team “shock compressed” an icy slush similar in composition to that found on comets, which are sometimes called “dirty snowballs” because they are a mixture of ice and rock. The compression, which researchers say is similar in intensity to comets hitting the Earth, generated amino acids – considered the basic bits of life.
“Our work shows that the basic building blocks of life can be assembled anywhere in the Solar System and perhaps beyond,” stated Zita Martins, a co-author of the paper who is with Imperial College London’s department of Earth science and engineering.
“However, the catch is that these building blocks need the right conditions in order for life to flourish. Excitingly, our study widens the scope for where these important ingredients may be formed in the Solar System and adds another piece to the puzzle of how life on our planet took root.”
An object entering a planet’s atmosphere. Credit: Imperial College London
Whether life arose on Earth, or was imported from other locations in the Solar System or universe, has been a hot-button topic for decades. Learning the answer not only has implications for our own planet, but also for understanding how likely it is that life exists in other Solar System planets and moons — not to mention moons or planets in other star systems.
The new experiment — which the researchers say uncovers evidence of a “cosmic factory” process for starting life — saw the team at the University of Kent and the Imperial College using a gas gun to send a projectile into an ice combination similar to what one would find a comet. After the impact, the researchers saw amino acids forming.
The work builds on research initially done by Nir Goldman, a scientist with the Lawrence Liverpool National Laboratory, who predicted the results based on simulations in the laboratory’s supercomputer. Goldman found that comets could have imported life’s building blocks (ammonia, methanol, carbon dioxide and water). Then, as they smashed into Earth, the energy produced could be enough to jump-start life.
The building blocks of proteins are molecules called amino acids. Most types of amino acids can exist in two different forms, one that is ‘left-handed’ and the other as ‘right-handed.’ Credit: NASA
“This process demonstrates a very simple mechanism whereby we can go from a mix of simple molecules, such as water and carbon-dioxide ice, to a more complicated molecule, such as an amino acid,” stated Mark Price, a co-author and physicist from the University of Kent.
“This is the first step towards life. The next step is to work out how to go from an amino acid to even more complex molecules such as proteins.”
You can read the research paper, which was published Sept. 15, on Nature Geoscience.
Is string theory right?
Is it just fantasy?
Caught in the landscape,
Out of touch with reality
Compactified
On S5 or T*S3
Space is a pure void
Why should it be stringy?
Because it’s quantum not classical
Nonrenormalizable
Any way you quantize
You’ll encounter infinity
You see
Quanta
Must interact
Via paths we understand
Using Feynman diagrams
Often, they will just rebound
But now and then they go another way
A quantum
Loooooop
Infinities will make you cry
Unless you can renormalize your model
Of baryons, fermions
And all other states of matter
Curved space:
The graviton
Can be thought of as a field
But these infinities are real
In a many-body
Loop diagram
Our results diverge no matter what we do…
A Quantum Soup (any way you quantize)
Kiss your fields goodbye
Guess Einstein’s theory wasn’t complete at all!
I see extended 1-D objects with no mass
What’s their use? What’s their use? Can they give us quark plasma?
What to minimize?
What functional describes this
String?
Nambu-Goto! (Nambu-Goto)
Nambu-Goto! (Nambu-Goto)
How to quantize I don’t know
Polyakov!
I’m just a worldsheet, please minimize me
He’s just a worldsheet from a string theory
Reperametrized by a Weyl symmetry!
Fermi, Bose, open, closed, orientable?
Vibrations
Modes! They become particles (particles!)
Vibrations
They become particles (particles!)
Vibrations
They become particles (particles!)
Become particles (particles!)
Become particles (many many many many particle…)
Modes modes modes modes modes modes modes!
Oh mamma mia mamma mia,
Such a sea of particles!
A tachyon, with a dilaton and gravity-vity-VITY
(rock out!)
Now we need ten dimensions and I’ll tell you why
(anomaly cancellation!)
So to get down to 4D we compactify!
Oh, Kahler!
(Kahler manifold)
Manifolds must be Kahler!
(Complex Reimannian symplectic form)
If we wanna preserve
Any of our super-symmetry
(Superstrings of type I, IIa and IIb)
(Heterotic O and Heterotic E)
(All are one through S and T duality)
(Thank you Ed Witten for that superstring revolution and your new M-theory!)
(Maldecena!)
(Super-Yang-Mills!)
(Type IIB String!)
Dual! Dual!
(In the AdS/CFT)
(Holography!)
Molecules and atoms
Light and energy
Time and space and matter
All from one united
Theory
Any way you quantize…
Lyrics and arrangement by Tim Blais and A Capella Science
Original music by Queen
An artist's conception of a disintegrating planet - creating a trail of dust - around its rocky star.
Solar flares – huge eruptions of charged particles from the Sun – present little threat to Earth. On a few rare occasions these particles may disrupt our communications systems and cause radio blackouts. But they tend to be more aesthetically pleasing than harmful. It’s certainly a sight to be seen as these energetic particles collide with our atmosphere, resulting in a cascade of colorful lights – the aurora borealis.
Fortunately our planet provides the protection necessary from such harmful space radiation. But not all planets are quite so lucky. Take for instance Kepler’s latest object of interest: KIC 12557548b, a super Mercury-size planet candidate. Astronomers have recently found that due to this star’s activity – producing massive stellar flares – the planet itself is evaporating.
Only last year, four different sources published evidence that this rocky planet was disintegrating. Thanks to Kepler, it quickly became clear that the total amount of light from KIC 12557548 as a function of time – the light curve of the system – dropped every 15.7 hours as a planet orbited it. But the amount of light blocked due to the transiting planet varied from 0.2% to more than 1.2%.
The amount of light blocked is dependent on the size of the planet. A Jupiter-size planet will block more light than a Mercury-size planet. The variations here suggest a range for the size of the planet: from a super Mercury-sized planet to a Jupiter-sized planet.
But this wasn’t the planet’s only enigma. It also has an asymmetric light curve. The total light from the star drops steadily as the planet begins its transit, plateaus as the planet fully covers the disk of the star, and then increases as the planet ends its transit. But the rate at which the light drops is much faster than the rate at which it increases. It takes longer for the light curve to return to its original brightness, hinting at a tail of debris that trails the planet, continuing to block light.
The light curves of KIC 12557548b. The left-hand plot represents deep transits, whereas the right-hand plot represents more shallow transits. Both plots show a clear asymmetry. Source: Brogi et al. 2012
It appears that the planet is evaporating – emitting small particles of dust into orbit, which then trails behind it. The varying transit depth reflects the amount of dust currently evaporating.
Recently a team from the University of Tokyo analyzed the system in more detail, attempting to explain why this tiny planet is evaporating. “We found that the transit depth negatively correlates with the modulation of the stellar flux,” Dr. Kawahara, lead author on the study, told Universe Today. “The dust amount increases when the planet is located in front of the star spots.”
The transit depth does not vary randomly, but every 22.83 days. This coincides with the modulation of the stellar flux, or simply the stellar rotation period. Star spots may be indirectly detected by a star’s noticeable decrease in stellar flux. Because these star spots are large (much larger than sunspots) they last for long periods of time, and may be used to deduce the star’s rotation period.
Kawahara et al. found that the transit depth periodically varies with the stellar rotation rate – finding a correlation between stellar activity and the rate at which the planet is evaporating.
“Energy from the star spots increases the amount of dust and atmosphere from the planet,” explains Dr. Kawahara. The extreme heat and wind is enough to speed up the motions of the dust molecules; making them fast enough to escape the planet’s gravitational pull.
Future spectroscopic studies may search for molecules in the evaporating atmosphere of KIC 12557548b. But Dr. Kawahara remarks that due to the planet’s faintness it is unlikely. His best hope is that future studies may instead find a similar object closer to us, that may be more easy to study.
The finding is published in The Astrophysical Journal Letters and is available for download here.
We all know that Saturn’s moon Enceladus has a whole arsenal of geysers jetting a constant spray of ice out into orbit (and if you didn’t know, learn about it here) but Enceladus isn’t the only place in the Saturnian system where jets can be found — there are some miniature versions hiding out in the thin F ring as well!
Watch the 50-mile-wide Prometheus dip into the F ring (CLICK TO PLAY) NASA/JPL/SSI. Animation by J. Major.
The image above, captured by the Cassini spacecraft on June 20, 2013, shows a segment of the thin, ropy F ring that encircles Saturn just beyond the A ring (visible at upper right). The bright barb near the center is what scientists call a mini jet, thought to be caused by small objects getting dragged through the ring material as a result of repeated passings by the shepherd moon Prometheus.
Coincidentally, it’s gravitational perturbations by Prometheus that help form the objects — half-mile-wide snowball-like clusters of icy ring particles — in the first place.
Unlike the dramatic jets on Enceladus, which are powered by tidal stresses that flex the moon’s crust, these mini jets are much more subtle and occur at the casual rate of 4 mph (2 meters/second)… about the speed of a brisk walk.
The reflective jets themselves can be anywhere from 25 to 112 miles (40 to 180 kilometers) long.
See more images of mini jets — also called “classic trails” — below:
Various images of mini jets captured by Cassini from 2005 to 2008.
Top of the Rock - New York City. Antares rocket and Cygnus cargo spacecraft approximate launch trajectory view as should be seen from atop Rockefeller Center, NYC, on Sept. 18, 2013 at 10:50 a.m. EDT - weather permitting - after blastoff from NASA Wallops, VA. Credit: Orbital Sciences See more Antares launch trajectory viewing graphics below
Top of the Rock – New York City
Antares rocket and Cygnus cargo spacecraft approximate launch trajectory view as should be seen from atop Rockefeller Center, NYC, on Sept. 18, 2013 at 10:50 a.m. EDT – weather permitting – after blastoff from NASA Wallops, VA. Credit: Orbital Sciences See more Antares launch trajectory viewing graphics below[/caption]
WALLOPS ISLAND, VA – “All Systems Are GO” for the Sept. 18 launch of Orbital Sciences Antares commercial rocket carrying the first ever fully functional Cygnus commercial resupply vehicle to orbit on the history making first flight blasting off from NASA’s Wallops Island Facility– along the eastern shore of Virginia and bound for the International Space Station (ISS).
Here’s our guide on “How to See the Antares/Cygnus Launch” – complete with viewing maps and trajectory graphics from a variety of prime viewing locations courtesy of Orbital Sciences, the private company that developed both the Antares rocket and Cygnus spaceship aimed at keeping the ISS fully operational for science research.
And although the launch is slated for late morning it should still be visible to millions of spectators along a lengthy swath of the US East Coast from North Carolina to Connecticut – weather permitting – who may have never before witnessed such a mighty rocket launch.
The daylight liftoff of the powerful two stage Antares rocket is scheduled for Wednesday, Sept 18 at 10:50 a.m. EDT from Launch Pad 0A at the Mid-Atlantic Regional Spaceport at NASA Wallops Island, Virginia. The launch window extends 15 minutes to 11:05 a.m.
Up top is the view as anticipated from “The Top of the Rock” or Rockefeller Center in New York City. See below the extraordinary image of LADEE’s launch from “Top of the Rock” by Ben Cooper to compare the day and night time sighting delights.
In anticipation of liftoff, the Antares rocket was rolled out to Pad 0A on Friday morning Sept. 13 and I was on hand for the entire event – see my rollout photos here and upcoming.
Seaside panoramic view of Antares rocket and Cygnus spacecraft after rollout to Launch Pad 0A at NASA Wallops at the Virginia Eastern Shore on Sept. 13, 2013. Blastoff for the ISS is slated for Sept. 18, 2013 at 10:50 a.m. EDT. LADEE launch pad 0B stands adjacent to right of Antares.
Credit: Ken Kremer (kenkremer.com)
Here’s a hi res version of the viewing map courtesy of NASA Wallops Flight Facility:
Antares/Cygnus Launch – Hi Res Visibility map
The Antares/Cygnus daylight rocket launch on Sept. 18, 2013 at 10:50 a.m. EDT from NASA Wallops, VA. will potentially be visible to millions of spectators along the Eastern US coast from Connecticut to North Carolina -weather permitting. This high resolution map shows the regions of visibility over time in the seconds after the rocket launch on a demonstration cargo resupply mission to the International Space Station. Credit: NASA Wallops Flight Facility
The Antares launch follows closely on the heels of the spectacularly bright Sept. 6 nighttime Moon shot blastoff of the Minotaur V rocket that successfully injected NASA’s LADEE lunar orbiter into its translunar trajectory.
And just as was the case with the Minotaur V and LADEE, you don’t have to be watching locally to join in and experience all the fun and excitement. As with any NASA launch, you can also follow along with up to the minute play by play by watching the NASA TV webcast online or on smartphones, iPods or laptops.
Atlantic City
It’s hard to say exactly how long and how bright the rockets flames and exhaust trail will be visible since it depends on the constantly changing lighting, prevailing clouds and overall weather conditions.
But one thing is for sure. If you don’t go outside and watch you’re giving up a great opportunity.
And keep in mind that Antares will be moving significantly slower than the Minotaur V.
Herein are a series of graphics showing the Antares trajectory and what you should see during firings of both stages from the perspective of standing on the ground or skyscrapers at a variety of popular destinations including Annapolis, the US Capitol, Lincoln Memorial, National Air and Space Museum, Atlantic City, NJ, New York City and more.
Capitol East-Front StepsGoddard Space Flight Center – GSFCAntares rocket and Cygnus spacecraft after rollout to Launch Pad 0A at NASA Wallops Flight Facility Facility, VA.,on Sept. 13, 2013. Blastoff is slated for Sept. 18, 2013 at 10:50 a.m. EDT. LADEE launch pad 0B stands adjacent to right of Antares. Credit: Ken Kremer (kenkremer.com)
The goal of the mission is to demonstrate the safe and successful launch, rendezvous and docking of the privately developed Cygnus cargo carrier with the International Space Station (ISS) and delivery of 1300 pounds of essential supplies, food, clothing, spare parts and science gear to the six person resident human crews – currently Expedition 37.
Although it’s the 2nd launch of Antares following the maiden flight in April, this is the first flight of the Cygnus commercial delivery system. The demonstration and testing will be the same as what SpaceX accomplished in 2012 with their competing Falcon 9/Dragon architecture.
The mission is designated Orb-D1 and is funded with seed money by NASA’s COTS program to replace the cargo delivery duties of NASA’s now retired Space Shuttle orbiters.
Lincoln MemorialRichmond
For those who are traveling to witness the launch locally in the Chincoteague, Va., area, there will be two public viewing sites said Jeremy Eggers, NASA Wallops Public Affairs Officer in an interview with Universe Today.
“There will be are two local sites open to the public,” Eggers told me. “Folks can watch at either the NASA Wallops Flight facility Visitors Center (http://sites.wff.nasa.gov/wvc) or the beach at Assateague National Seashore (http://www.nps.gov/asis/index.htm).”
“There will be loudspeakers to follow the progress of the countdown, but no TV screens as done with the LADEE launch.”
National Air & Space Udvar-Hazy MuseumAnnapolis
So far the weather outlook is promising with a 75% chance of “GO” with favorable conditions at launch time.
NASA Television coverage of the Antares launch will begin at 10:15 a.m. on Sept 18 – (www.nasa.gov/ntv).
Be sure to watch for my continuing Antares and LADEE mission reports from on site at NASA’s Wallops Launch Pads in sunny Virginia – reporting for Universe Today.
Learn more about Cygnus, Antares, LADEE, Curiosity, Mars rovers, MAVEN, Orion and more at Ken’s upcoming presentations
Sep 17/18: LADEE Lunar & Antares/Cygnus ISS Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA
Oct 3: “Curiosity, MAVEN and the Search for Life on Mars – (3-D)”, STAR Astronomy Club, Brookdale Community College & Monmouth Museum, Lincroft, NJ, 8 PM
Oct 8: LADEE Lunar & Antares/Cygnus ISS Rocket Launches from Virginia”; Princeton University, Amateur Astronomers Assoc of Princeton (AAAP), Princeton, NJ, 8 PM
This magnificent view of NASA’s LADEE lunar orbiter launched on Friday night Sept 6, on the maiden flight of the Minotaur V rocket from Virginia was captured by space photographer Ben Cooper perched atop Rockefeller Center in New York City. Compare this actual launch view to the graphic calculated for Antares (above) as seen from the exact same location atop Rockefeller Center. Credit: Ben Cooper/Launchphotography.com
A full solar halo -- plus a dragonfly -- seen above John Chumack's observatory dome on September 15, 2013. Credit and copyright: John Chumack/Galactic Images.
A beautiful atmospheric effect wasn’t the only thing hovering above John Chumack’s observatory dome this weekend. A dragonfly flits over John’s observatory in Dayton, Ohio, joining a spectacular solar halo, a ring around the Sun created by ice crystals in Earth’s atmosphere. John used a simple point & shoot Canon XS 160 camera to capture the scene.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
Signs posted outside launch Pad-OA at the NASA Wallops Flight Facility. Credit: NASA/Bill Ingalls.
These custom road signs at NASA’s Wallops Flight Facility are, well, out of this world with awesomeness. They refer to the recent launch of the LADEE spacecraft to the Moon and the upcoming launch this week of the Orbital Sciences Corporation Antares rocket, with its Cygnus cargo spacecraft heading to the International Space Station for a demonstration cargo resupply mission. Launch is currently scheduled for Wednesday, September 18 during a window of 10:50-11:05 am EDT (14:50-15:05 UTC).
