A recovery vessel lifts the Low-Density Supersonic Decelerator aboard after its June 28, 2014 test over the U.S. Navy's Pacific Missile Range. Credit: NASA/JPL-Caltech
Although the parachute didn’t pop out during a flight test this weekend of NASA’s flying-saucer shaped prototype spacecraft for future Mars exploration, the agency says the so-called Low-Density Supersonic Decelerator performed to expectations.
In an update released yesterday (June 30), one day after the craft made a hard landing in the Pacific, the agency noted that every goal on the flight had been met. The nature of the parachute failure is being investigated; the parachute was a year ahead of schedule in its development, according to NASA.
“The test vehicle worked beautifully, and we met all of our flight objectives,” stated Mark Adler, project manager for LDSD at NASA’s Jet Propulsion Laboratory in California. “We have recovered all the vehicle hardware and data recorders and will be able to apply all of the lessons learned from this information to our future flights.”
The flight test (which had been delayed for some time due to weather) saw LDSD soar into the sky on a high-altitude balloon launch that took it up to 120,000 feet (36,576 meters). As planned, the test vehicle was severed from the balloon to see how well it would perform during a simulated descent to the Martian surface.
The Low-Density Supersonic Decelerator (LDSD) soars into the sky during a test flight June 28, 2014 (invisible at top of contrail) while its carrier balloon floats in the frame. Credit: NASA/JPL-Caltech
With Martian spacecraft getting heavier, NASA is testing out new technologies to control spacecraft during the landing that would safely be able to navigate the Red Planet’s thin atmosphere. This test was supposed to see the LDSD leave the balloon while spinning sideways (somewhat like a football) and zoom to four times the speed of sound.
Next, it was supposed to deploy a Supersonic Inflatable Aerodynamic Decelerator to slow down to 2.5 Mach (speed of sound) and then pop the parachute. The SIAD did inflate as planned, but not the parachute.
“All indications are that the SIAD deployed flawlessly, and because of that, we got the opportunity to test the second technology, the enormous supersonic parachute, which is almost a year ahead of schedule,” stated Ian Clark, principal investigator for LDSD at JPL.
Sooner or later we’re going to want to move the Earth further away from the Sun. It turns out, there are a few techniques that might actually make this possible. Not easy, but possible.
You live here. I live here. Everybody lives here. For now.
In 500 million years the gradual heating of the Sun will burn away all life on Earth. Then we might have to move. Even if we get past the 500 million year deadline, the Sun will die as a red giant in about 5 billion years.
Let’s review our options? We could die… orrrr we could move the Earth. Just like any other mad science scheme, there’s a hundred ways to skin this cat. We could launch powerful rockets off the Earth, which would push the Earth a little bit in the opposite direction.
We could build a giant teleporter and disassemble the Earth atom by atom into a new location. We could repeatedly smash things into the Earth. Eventually knocking it off orbit, possibly also changing its axis and or rotation.
We could paint half the Earth silver, stop it rotating and let the Sun push it away. We could dig a giant hole down to the core and repeatedly detonate warheads inside the Earth forcing molten material to fly off into space, propelling us forwards like a deflating balloon.
Sure, maybe that does all sound a little crazy. We could build a gravity tug, and slowly pull the Earth away from the Sun. What’s a gravity tug? I’m so glad you asked.
You could build a solar sail with a huge mass connected to it. This gigantic weight would want to fall towards the Earth, and the Earth slowly drifts towards the weight. The solar sail is being pushed away by the Sun dragging both the weight and as a result the Earth along with it. This would take a very, very, very long time.
The Solar Sail demonstration mission. Credit: NASA
Here’s the best idea scientists have come up with so far. Gravity assists: Attach rockets to an asteroid, comet or Kuiper belt object and have it fall on a trajectory that takes it close to the Earth. Earth and this space rock would exchange a little momentum.
The rock slows down a bit and goes into a new orbit, and the Earth speeds up a little. That additional momentum pushes our orbit up a tiny little bit, and now we’re further away from the Sun. You’d need to do this tens of thousands or even a million times.
You might think, “Hey, that’s crazy. Where would you get all this stuff to hurl past the Earth?”. Don’t worry, the Oort cloud alone has billions of objects with a total of 30 times the mass of the Earth.
To prepare for Roastpocalypse, If we started now, we should cause a close pass with a large object every few thousand years. We bring them within 10,000 km of the surface of the Earth, which would have the likely side effect of causing severe tides and storms.
The layout of the solar system, including the Oort Cloud, on a logarithmic scale. Credit: NASA
Oh, and get the math wrong and you’ll smash an asteroid into the Earth. Just so you know, these would be way bigger than the object that killed the dinosaurs. One hit from a 100km diameter object would sterilize the biosphere.
If we pushed the Earth out to about 1.5 times its current orbit, which might get a little too cozy with Mars for comfort, we’d give the Earth another 5 billion years of habitability,
Then the Sun turns into a red giant, and then dies as a white dwarf. And nothing can help us then… except perhaps some kind of planet sized star gate.
What do you think? What’s the best suggestion you’ve got to move the Earth out to a safe distance? Tell us in the comments below.
NASA’s Orbiting Carbon Observatory-2 (OCO-2) at the Launch Pad. This black-and-white infrared view shows the launch gantry, surrounding the United Launch Alliance Delta II rocket with the Orbiting Carbon Observatory-2 (OCO-2) satellite onboard. The photo was taken at Space Launch Complex 2, Friday, June 27, 2014, Vandenberg Air Force Base, Calif. OCO-2 is set for a July 1, 2014 launch. Credit: NASA/Bill Ingalls
NASA’s Orbiting Carbon Observatory-2 (OCO-2) at the Launch Pad
This black-and-white infrared view shows the launch gantry, surrounding the United Launch Alliance Delta II rocket with the Orbiting Carbon Observatory-2 (OCO-2) satellite onboard. The photo was taken at Space Launch Complex 2, Friday, June 27, 2014, Vandenberg Air Force Base, Calif. OCO-2 is set for a July 1, 2014 launch. Credit: NASA/Bill Ingalls[/caption]
After a lengthy hiatus, the workhorse Delta II rocket that first launched a quarter of a century ago and placed numerous renowned NASA science missions into Earth orbit and interplanetary space, as well as lofting dozens of commercial and DOD missions, is about to soar again this week on July 1 with NASA’s Orbiting Carbon Observatory-2 (OCO-2) sniffer to study atmospheric carbon dioxide (CO2).
OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas and the principal human-produced driver of climate change.
The 999 pound (454 kilogram) observatory is equipped with one science instrument consisting of three high-resolution, near-infrared spectrometers fed by a common telescope. It will collect global measurements of atmospheric CO2 to provide scientists with a better idea of how CO2 impacts climate change. OCO-2’s Delta II Rocket, First Stage At Space Launch Complex 2 on Vandenberg Air Force Base in California, the mobile service tower rolls away from the launch stand supporting the first stage of the Delta II rocket for NASA’s Orbiting Carbon Observatory-2 mission. Three solid rocket motors (white) have been attached to the first stage. The photo was taken during operations to mate the rocket’s first and second stages. Credit: NASA/Randy Beaudoin
The $467.7 million OCO-2 mission is set to blastoff atop the United Launch Alliance (ULA) Delta II rocket on Tuesday, July 1 from Space Launch Complex 2 at Vandenberg Air Force Base in California.
Liftoff is slated for 5:56 a.m. EDT (2:56 a.m. PDT) at the opening of a short 30-second launch window.
The California weather prognosis is currently outstanding at 100 percent ‘GO’ for favorable weather conditions at launch time.
OCO-2 poster. Credit: ULA/NASA
The two stage Delta II 7320-10 launch vehicle is 8 ft in diameter and approximately 128 ft tall. It is equipped with a trio of strap on solid rocket motors. This marks the 152nd Delta II launch overall and the 51st for NASA since 1989.
The last time a Delta II rocket flew was nearly three years ago in October 2011 from Vandenberg for the Suomi National Polar-Orbiting Partnership (NPP) weather satellite.
The Delta II will boost OCO-2 into a 438-mile (705-kilometer) altitude, near-polar orbit. Spacecraft separation from the rocket occurs 56 minutes 15 seconds after launch.
It will lead a constellation of five other international Earth monitoring satellites that circle Earth.
NASA’s Orbiting Carbon Observatory-2, or OCO-2, inside the payload fairing in the mobile service tower at Space Launch Complex 2 on Vandenberg Air Force Base in California. The fairing will protect OCO-2 during launch aboard a United Launch Alliance Delta II rocket, scheduled for 5:56 a.m. EDT on July 1. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. Credit: NASA/30th Space Wing USAF
The phone-booth sized OCO-2 was built by Orbital Sciences and is a replacement for the original OCO which was destroyed during the failed launch of a Taurus XL rocket from Vandenberg back in February 2009 when the payload fairing failed to open properly.
OCO-2 is the second of NASA’s five new Earth science missions launching in 2014 and is designed to operate for at least two years during its primary mission. It follows the successful blastoff of the joint NASA/JAXA Global Precipitation Measurement (GPM) Core Observatory satellite on Feb 27.
Orbiting Carbon Observatory-2 (OCO-2) mission will provide a global picture of the human and natural sources of carbon dioxide, as well as their “sinks,” the natural ocean and land processes by which carbon dioxide is pulled out of Earth’s atmosphere and stored, according to NASA..
“Carbon dioxide in the atmosphere plays a critical role in our planet’s energy balance and is a key factor in understanding how our climate is changing,” said Michael Freilich, director of NASA’s Earth Science Division in Washington.
“With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future.”
Artist’s rendering of NASA’s Orbiting Carbon Observatory (OCO)-2, one of five new NASA Earth science missions set to launch in 2014, and one of three managed by JPL. Credit: NASA-JPL/Caltech
It will record around 100,000 CO2 measurements around the world every day and help determine its source and fate in an effort to understand how human activities impact climate change and how we can mitigate its effects.
At the dawn of the Industrial Revolution, there were about 280 parts per million (ppm) of carbon dioxide in Earth’s atmosphere. As of today the CO2 level has risen to about 400 parts per million.
Stay tuned here for Ken’s continuing OCO-2, GPM, Curiosity, Opportunity, Orion, SpaceX, Boeing, Orbital Sciences, MAVEN, MOM, Mars and more Earth & Planetary science and human spaceflight news.
Blastoff of twin GRAIL A and B lunar gravity mapping spacecraft on a Delta II Heavy rocket on Sept. 10, 2011, from Pad 17B Cape Canaveral Air Force Station in Florida at 9:08 a.m. EDT. Credit: Ken Kremer/kenkremer.com
A test version of NASA’s Orion manned spacecraft descends under its three main parachutes above the U.S. Army Proving Ground in Arizona in the agency’s most difficult test of the parachutes system’s performance to prepare Orion for its first trip to space in December 2014. Credit: NASA/Rad Sinyak
A test version of NASA’s Orion deep space capsule has completed its most complex and last full flight-like parachute drop test on June 25 ahead of the maiden launch on the EFT-1 mission now slated for early December 2014.
The descent test was conducted at an altitude of 35,000 feet over the Arizona desert at the U.S. Army’s Yuma Proving Ground by pulling the test vehicle out of a huge C-17 cargo aircraft.
The test also included the addition of several added stress tests to check out the ability of the parachute system to compensate and examine capsule and astronaut crew survival via several potential failure modes.
For example, engineers rigged one of the main parachutes to skip the intermediate phase of the three-phase process to unfurl each of Orion’s three parachutes, called reefing.
“This tested whether one of the main parachutes could go directly from opening a little to being fully open without an intermediary step, proving the system can tolerate potential failures,” according to NASA.
The goal is to prove that that parachute system will slow Orion to ensure a safe landing speed for the astronaut crews returning from deep space missions to the Moon, Asteroids and eventually Mars.
The Orion crew module for Exploration Flight Test-1 is shown in the Final Assembly and System Testing (FAST) Cell, positioned over the service module just prior to mating the two sections together. Credit: NASA/Rad Sinyak
“We’ve put the parachutes through their paces in ground and airdrop testing in just about every conceivable way before we begin sending them into space on Exploration Flight Test (EFT)-1 before the year’s done,” said Orion Program Manager Mark Geyer in a state
“The series of tests has proven the system and will help ensure crew and mission safety for our astronauts in the future.”
Orion is slated to launch on its inaugural unmanned EFT-1 test flight in December 2014 atop the mammoth, triple barreled United Launch Alliance (ULA) Delta IV Heavy rocket from Cape Canaveral, Florida.
Orion crew capsule, Service Module and 6 ton Launch Abort System (LAS) mock up stack inside the transfer aisle of the Vehicle Assembly Building (VAB) at the Kennedy Space Center (KSC) in Florida. Service module at bottom. Credit: Ken Kremer/kenkremer.com
This test also marked the last time that the entire parachute sequence involving the deployment of all three 116 foot-wide main chutes will be tested before the December launch.
For some of the parachutes, this was the highest altitude drop test attempted.
“Engineers also put additional stresses on the parachutes by allowing the test version of Orion to free fall for 10 seconds, which increased the vehicle’s speed and aerodynamic pressure,” NASA noted in a statement.
The parachute deployment and unfurling can only begin after jettisoning of the spacecraft’s forward bay cover. The chutes are housed below the cover which protects the chutes until reentry into Earth’s atmosphere.
The two-orbit, four- hour EFT-1 flight will lift the Orion spacecraft and its attached second stage to an orbital altitude of 3,600 miles, about 15 times higher than the International Space Station (ISS) – and farther than any human spacecraft has journeyed in 40 years.
One of the primary goals of NASA’s eagerly anticipated Orion EFT-1 uncrewed test flight is to test the efficacy of the heat shield in protecting the vehicle – and future human astronauts – from excruciating temperatures reaching 4000 degrees Fahrenheit (2200 C) during scorching re-entry heating.
At the conclusion of the EFT-1 flight, the detached Orion capsule plunges back and re-enters the Earth’s atmosphere at 20,000 MPH (32,000 kilometers per hour).
“That’s about 80% of the reentry speed experienced by the Apollo capsule after returning from the Apollo moon landing missions,” Scott Wilson, NASA’s Orion Manager of Production Operations at KSC, told me during an interview at KSC.
The parachute system comprising of two drogue parachutes and a trio of main parachutes – nearly the size of a football field – will then unfurl to slow Orion down to just 20 mph for a safe splashdown and recovery by the US Navy in the Pacific Ocean.
The Orion EFT-1 mission will end with a splashdown in the Pacific Ocean. During the stationary recovery test of Orion at Norfolk Naval Base on Aug. 15, 2013, US Navy divers attached tow lines and led the test capsule to a flooded well deck on the USS Arlington. Credit: Ken Kremer/kenkremer.com.
Another drop test scheduled for August will test the combined failure of one drogue parachute and one main parachute, as well as new parachute design features, says NASA.
Meanwhile, Orion’s prime contractor Lockheed Martin is finishing assembly and test operations of the EFT-1 capsule inside the Operations and Checkout Facility (O & C) at the Kennedy Space Center (KSC) flying in December’s launch
Stay tuned here for Ken’s continuing Orion, Orbital Sciences, SpaceX, commercial space, Curiosity, Mars rover, MAVEN, MOM and more planetary and human spaceflight news.
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/MSSS
Here’s the latest interactive panorama via panoramacist Andrew Bodrov from imagery taken by the Curiosity Mars at Gale Crater, from Sol 647 (May 1, 2014).
The images for panorama were obtained by the rover’s 34-millimeter Mast Camera. The mosaic, which stretches about 30,000 pixels width, includes 134 images, all taken on Sol 647.
You can see previous interactive panoramas from Andrew of of Curiosity’s images here.
And in case you missed it, here’s Curiosity’s latest “Selfie”:
Ethereal and stunning sundog-like forms in the clouds over Oxford, England on June 25, 2014. Credit and copyright: Nathanial Burton-Bradford.
My Twitter feed exploded on June 25 with reports of colorful, crazy-looking clouds, sundogs, Sun halos and more. The above image from Nathanial Burton-Bradford is just an example of the type of atmospheric effect called a circumhorizontal arc. These are sometimes referred to as “fire rainbows” but of course are not rainbows, and fire plays no role.
This is an optical phenomenon from sunlight hitting ice crystals in high cirrus clouds. It is actually a rather rare occurrence, but it happens most often during the daytime in summer when the Sun is high in the sky. This creates a rainbow-type effect directly in the ice crystal-filled clouds.
See more examples below.
Wispy clouds and a circumhorizontal arc over Italy. Credit and copyright: Elisabetta Bonora.Circumhorizontal Arc over the UK on June 25, 2014. Credit and copyright: Sculptor Lil on Flickr.
XCOR Aerospace's Lynx suborbital vehicle is designed to fly to 328,000 feet (Credit: XCOR)
Well, technically not space*, but suborbital, and that’d still be way cool! And what’s even cooler is that you can enter to win a trip on an XCOR Lynx Mark II suborbital flight while helping to support a good cause of your choice, courtesy of The Urgency Network’s “Ticket to Rise” campaign. Check out the dramatic spaceflight-packed promotional video and find out how to enter below:
The Urgency Network is an online platform whereby participants can win experience-based prizes by participating in campaigns that are designed to aid and support good causes, many of which assist specific communities in need, awareness groups, and conservation efforts. You earn “entries” for prize drawings by purchasing gift packages from the participating foundations or by donating time, social media presence, or money directly. It’s a way for organizations that might not have (or be able to afford) a large PR department to get funded and gain widespread exposure. Learn more about The Urgency Network here.
In the Ticket to Rise campaign, the grand prize is beyond stratospheric — literally! One lucky winner will experience a ride aboard an XCOR Lynx Mark II suborbital craft, a single-stage space vehicle that takes off from a runway to ultimately coast briefly at a maximum altitude of 328,000 feet (about 100 km), experiencing 4 minutes of microgravity before re-entry and a runway landing. It’s a supersonic 30-minute flight to the very edge of space!
(*Actually, 100 km is right at the von Karman line, so riding the Lynx Mark II past that could qualify you as an astronaut. Just sayin’.)
How a Lynx Mark II flight works (Source: XCOR)
Add to that you’d be helping any one of dozens of good causes (you can choose from different ones by clicking the “Select a Different NonProfit” text link on the donation page) and it’s a win-win for everyone. And even if you don’t get a seat aboard a spaceship (many will enter, few will win) you can still get some pretty awesome promo offers from the organizations as bulk-entry packages.
The deadline to enter the campaign is 11:59:59 p.m. EDT August 11, 2014. Drawing will be held on August 12. The Lynx flight is dependent on meeting all requirements and passing physical exams and tests by XCOR Aerospace, and although the date is expected to be in the fall of 2015, this is rocket science and things change. Read the official contest rules for all details, fine print, etc.
Artists illustration of the expansion of the Universe (Credit: NASA, Goddard Space Flight Center)
This week at the Royal Astronomical Society’s National Astronomy Meeting in the UK, physicists are challenging the evidence for the recent BICEP2 results regarding the inflation period of the Universe, announced just 90 days ago. New research is laying doubt upon the inclusion of inflation theory in the Standard Cosmological Model for understanding the forces of nature, the nature of elementary particles and the present state of the known Universe.
Back on March 17, 2014, it seemed the World was offered a glimpse of an ultimate order from eons ago … actually from the beginning of time. BICEP2, the single purpose machine at the South Pole delivered an image that after analysis, and subtraction of estimated background signal from the Milky Way, lead its researchers to conclude that they had found the earliest remnant from the birth of the Universe, a signature in ancient light that supported the theory of Inflation.
BICEP2 Telescope at twilight at the South Pole, Antarctica (Credit: Steffen Richter, Harvard University)
Thirty years ago, the Inflation theory was conceived by physicists Alan Guth and Andei Linde. Guth, Linde and others realized that a sudden expansion of the Universe at only 1/1000000000000000000000000000000000th of a second after the Big Bang could solve some puzzling mysteries of the Cosmos. Inflation could explain the uniformity of the cosmic background radiation. While images such as from the COBE satellite show a blotchy distribution of radiation, in actuality, these images accentuate extremely small variations in the background radiation, remnants from the Big Bang, variations on the order of 1/100,000th of the background level.
Note that the time of the Universe’s proposed Inflationary period immediately after the Big Bang would today permit light to travel only 1/1000000000000000th of the diameter of the Hydrogen atom. The Universe during this first moment of expansion was encapsulated in a volume far smaller than the a single atom.
Emotions ran very high when the BICEP2 team announced their findings on March 17 of this year. The inflation event that the background radiation data supported is described as a supercooling of the Cosmos however, there were physicists that simply remained cool and remained contrarians to the theory. Noted British Physicist Sir Roger Primrose was one who remained underwhelmed and stated that the incredible circular polarization of light that remained in the processed data from BICEP2 could be explained by the interaction of dust, light and magnetic fields in our own neighborhood, the Milky Way.
Illustration of the ESA Planck Telescope in Earth orbit (Credit: ESA)
Now, new observations from another detector, one on the Planck Satellite orbiting the Earth, is revealing that the contribution of background radiation from local sources, the dust in the Milky Way, is appearing to have been under-estimated by the BICEP2 team. All the evidence is not yet laid out but the researchers are now showing reservations. At the same time, it does not dismiss the Inflation Theory. It means that more observations are needed and probably with greater sensitivity.
So why ask the question, are physicists constructing a Rube Goldberg device?
Our present understanding of the Universe stands upon what is called “the Standard Model” of Cosmology. At the Royal Astronomical Society meeting this week, the discussions underfoot could be revealing a Standard Model possibly in a state of collapse or simply needing new gadgets and mechanisms to remain the best theory of everything.
Also this week, new data further supports the discovery of the Higg’s Boson by the Large Hadron Collider in 2012, the elementary particle whose existence explains the mass of fundamental particles in nature and that supports the existence of the Higgs Field vital to robustness of the Standard Model. However, the Higgs related data is also revealing that if the inflationary period of the Universe did take place, then if taken with the Standard Model, one can conclude that the Universe should have collapsed upon itself and our very existence today would not be possible.
A Rube Goldberg Toothpaste dispenser as also the state of the Standard Model (Credit: R.Goldberg)
Dr. Brian Green, a researcher in the field of Super String Theory and M-Theory and others such as Dr. Stephen Hawking, are quick to state that the Standard Model is an intermediary step towards a Grand Unified Theory of everything, the Universe. The contortion of the Standard Model, into a sort of Rube Goldberg device can be explained by the undaunting accumulation of more acute and diverse observations at cosmic and quantum scales.
Discussions at the Royal Astronomical Society meeting are laying more doubts upon the inflation theory which just 90 days ago appeared so well supported by BICEP2 – data derived by truly remarkable cutting edge electronics developed by NASA and researchers at the California Institute of Technology. The trials and tribulations of these great theories to explain everything harken back to the period just prior to Einstein’s Miracle Year, 1905. Fragmented theories explaining separately the forces of nature were present but also the accumulation of observational data had reached a flash point.
Today, observations from BICEP2, NASA and ESA great space observatories, sensitive instruments buried miles underground and carefully contrived quantum experiments in laboratories are making the Standard Model more stressed in explaining everything, the same model so well supported by the Higg’s Boson discovery just two years ago. Cosmologists concede that we may never have a complete, proven theory of everything, one that is elegant; however, the challenges upon the Standard Model and inflation will surely embolden younger theorists to double the efforts in other theoretical work.
Have you ever noticed that everything in space is a sphere? The Sun, the Earth, the Moon and the other planets and their moons… all spheres. Except for the stuff which isn’t spheres. What’s going on?
Have you noticed that a good portion of things in space are shaped like a sphere? Stars, planets, and moons are all spherical.
Why? It all comes down to gravity. All the atoms in an object pull towards a common center of gravity, and they’re resisted outwards by whatever force is holding them apart. The final result could be a sphere… but not always, as we’re about to learn.
Consider a glass of water. If you could see the individual molecules jostling around, you’d see them trying to fit in as snugly as they can, tension making the top of the water smooth and even.
Imagine a planet made entirely of water. If there were no winds, it would be perfectly smooth. The water molecules on the north pole are pulling towards the molecules on the south pole. The ones on the left are pulling towards the right. With all points pulling towards the center of the mass you would get a perfect sphere.
Gravity and surface tension pull it in, and molecular forces are pushing it outward. If you could hold this massive water droplet in an environment where it would remain undisturbed, eventually the water would reach a perfect balance. This is known as “hydrostatic equilibrium”.
Stars, planets and moons can be made of gas, ice or rock. Get enough mass in one area, and it’s going to pull all that stuff into a roughly spherical shape. Less massive objects, such as asteroids, comets, and smaller moons have less gravity, so they may not pull into perfect spheres.
Jupiter Credit: Christopher Go
As you know, most of the celestial bodies we’ve mentioned rotate on an axis, and guess what, those ones aren’t actually spheres either. The rapid rotation flattens out the middle, and makes them wider across the equator than from pole to pole. Earth is perfect example of this, and we call its shape an oblate spheroid.
Jupiter is even more flattened because it spins more rapidly. A day on Jupiter is a short 9.9 hours long. Which leaves it a distorted imperfect sphere at 71,500 km across the equator and just 66,900 from pole to pole.
Stars are similar. Our Sun rotates slowly, so it’s almost a perfect sphere, but there are stars out there that spin very, very quickly. VFTS 102, a giant star in the Tarantula nebula is spinning 100 times faster than the Sun. Any faster and it would tear itself apart from centripetal forces.
This oblate spheroid shape helps indicate why there are lots of flattened disks out there. This rapid spinning, where centripetal forces overcome gravitational attraction that creates this shape. You can see it in black hole accretion disks, solar systems, and galaxies.
Objects tend to form into spheres. If they’re massive enough, they’ll overcome the forces preventing it. But… if they’re spinning rapidly enough, they’ll flatten out all the way into disks.
An Iridium Flare flashes over western Maine in this beautiful night sky image from June 2014. Credit and copyright: Mike Taylor/Taylor Photography.
Ever seen a flash in the night sky and wondered if you were seeing things? Iridium flares are often mistaken for meteors because of their notable bright flashes of light in the night sky but they are actually caused by a specific group of satellites that orbit our planet. The Iridium communication satellites are just in the right orbit that when sunlight reflects on their antennas, a flash — or flare — is visible down on Earth. There are currently about 66 Iridium satellites in orbit, so flares are a rather common occurrence.
This image from photographer Mike Taylor is one frame from a timelapse of the Milky Way and other features of the night sky in motion against a silhouetted foreground. “Photographed from western Maine, this shot includes quite a bit of light pollution and some fast moving cloud cover,” Mike told Universe Today via email. “Most of the light pollution in this image is coming from Farmington, Maine which is about 35 miles from this location.”
Mike added the footage from this timelapse will be featured in his upcoming short film “Shot In The Dark.”
He also provided this info about Iridium flares:
Iridium satellites are in near-polar orbits at an altitude of 485 miles. Their orbital period is approximately 100 minutes with a velocity of 16,800 miles per hour. The uniqueness of Iridium flares is that the spacecraft emits ‘flashes’ of very bright reflected light that sweep in narrow focused paths across the surface of the Earth. An Iridium communication satellite’s Main Mission Antenna is a silver-coated Teflon antenna array that mimics near-perfect mirrors and are angled at 40-degrees away from the axis of the body of the satellites. This can provide a specular reflection of the Sun’s disk, periodically causing a dazzling glint of reflected sunlight. At the Earth’s surface, the specular reflection is probably less than 50 miles wide, so each flare can only be viewed from a fairly small area. The flare duration can last from anywhere between 5 to 20 seconds and can easily be seen by the naked eye.
If you want to try and see an Iridum flare for yourself, check out Heavens Above for your location.
For this image Mike used:
Nikon D600 & 14-24 @ 14mm
f/2.8 – 30 secs – ISO 3200 – WB Kelvin 3570
06/23/14 – 11:07PM
Processed via Lightroom 5 & Photoshop CS5
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