Sergei Krikalev gives a thumbs up during suit check before the launch of STS-88 in 1998. Credit: NASA.
Is time travel a fact or is it just science fiction? Thanks to time dilation and Einstein’s theory of relativity, we know that time travel can and actually does happen, albeit only in extremely tiny increments at the speeds and distances we can travel in space. If you add up the accumulated speed cosmonaut Sergei Krivalev has traveled in space – the most of any human with a total time spent in orbit of 803 days 9 hours and 39 minutes – he has actually time-traveled into his own future by 0.02 seconds.
Time dilation is caused by differences in either gravity or relative velocity — each of which affects time in different ways. When astronauts and satellites orbit the Earth, they are slightly further away from the center of the planet –compared to people on the ground – and so they actually experience less gravitational time dilation. This means the astronauts’ time would run slightly faster, and when they return to Earth, they’d have to “come back” to the past compared to when they were in space.
But time dilation due to velocity means that clocks for astronauts in space run slightly slower relative to people who are on the ground. When you come back to Earth, you’d be have to go into the future slightly to catch up with clocks on the ground.
The effect of time dilation due to gravity, however, “is quite small because Earth’s gravity is quite weak,” says educator Colin Stuart in this great instructional video from TedEd, “and so the time dilation due to their speed wins out and astronauts really do travel a tiny amount into their futures.”
But, as stated earlier, with our current technology limiting the velocities of astronauts, these differences are minuscule: after 6 months on the ISS, an astronaut has aged less than those on Earth, but only by about 0.007 seconds. The effects would be greater if we could get the ISS to orbit Earth at near the speed of light (approximately 300,000 km/s), instead of the actual speed of about 7.7 km/s.
This effect has been proven by GPS satellites, which orbit Earth at about 14,000 km/h (9,000 mph) which cuts several microseconds off their clocks daily, relative to clocks on Earth.
The Cygnus commercial resupply craft departed the ISS this morning (Oct. 22) to complete its maiden voyage after being released from Canadarm2 by station astronauts. Credit: NASA TV
Commercial space took another major leap forward this morning, Oct 22., when the privately developed Cygnus cargo vehicle undocked from the International Space Station on its historic maiden flight and successfully completed a highly productive month long stay during its demonstration mission – mostly amidst the US government shutdown.
The Cygnus was maneuvered about 10 meters (30 feet) away from the station and held in the steady grip of the stations fully extended robotic arm when astronauts Karen Nyberg and Luca Parmitano unlatched the arm and released the ship into free space at 7:31 a.m. EDT today – signifying an end to joint flight operations.
The next Cygnus resupply vessel is due to blast off in mid-December and is already loaded with new science experiments for microgravity research and assorted gear and provisions.
After the Expedition 37 crew members quickly pulled the arm back to a distance 1.5 meters away from Cygnus, ground controllers issued a planned “abort” command to fire the ships thrusters and safely depart from the massive orbiting lab complex.
Space Station robotic arm releases Cygnus after detachment from the ISS Harmony node. Credit: NASA TV
“It’s been a great mission. Nice work today!” radioed Houston Mission Control at NASA’s Johnson Space Center.
The vehicles were flying over the Atlantic Ocean and off the east coast of Argentina as Cygnus left the station some 250 miles (400 km) overhead in low Earth orbit.
The event was carried live on NASA TV and Cygnus was seen moving rapidly away.
Barely five minutes later Cygnus was already 200 meters away, appeared very small in the cameras view and exited the imaginary “Keep Out Sphere” – a strictly designated safety zone around the million pound station.
Cygnus commercial cargo craft rapidly departed the ISS this morning (Oct. 22) after release from the Canadarm2 robotic arm. Station modules visible at bottom. Credit: NASA TV
The Cygnus resupply ship delivered about 1,300 pounds (589 kilograms) of cargo, including food, clothing, water, science experiments, spare parts and gear to the six person Expedition 37 crew.
After the crew unloaded all that cargo, they packed the ship with 2,850 pounds of no longer needed trash.
On Wednesday (Oct. 23), a pair of deorbit burns with target Cygnus for a destructive reentry back into the Earth’s atmosphere at 2:18 p.m. EDT, to plummet harmlessly into the Pacific Ocean.
Cygnus was developed by Orbital Sciences Corp. with seed money from NASA in a public-private partnership between NASA and Orbital Sciences under NASA’s COTS commercial transportation initiative.
SpaceX Corp. was also awarded a COTS contract to develop the Dragon cargo carrier so that NASA would have a dual capability to stock up the station.
COTS was aimed at fostering the development of America’s commercial space industry to deliver critical and essential supplies to the ISS following the retirement of the Space Shuttle program.
“Congratulations to the teams at Orbital Sciences and NASA who worked hard to make this demonstration mission to the International Space Station an overwhelming success,” NASA Administrator Charles Bolden said in a statement.
Antares rocket lifts off at 10:58 a.m. EDT Sept 18 with commercial Cygnus cargo resupply ship bound for the International Space Station (ISS) from Mid-Atlantic Regional Spaceport Pad-0A at NASA’s Wallops Flight Facility in Virginia. Credit: Ken Kremer (kenkremer.com)
“We are delighted to now have two American companies able to resupply the station. U.S. innovation and inspiration have once again shown their great strength in the design and operation of a new generation of vehicles to carry cargo to our laboratory in space. Orbital’s success today is helping make NASA’s future exploration to farther destinations possible.”
America completely lost its capability to send humans and cargo to the ISS when NASA’s space shuttles were forcibly retired in 2011. Orbital Sciences and SpaceX were awarded NASA contracts worth over $3 Billion to restore the unmanned cargo resupply capability over 20 flights totally.
“Antares next flight is scheduled for mid December,” according to Frank Culbertson, former astronaut and now Orbital’s executive Vice President responsible for the Antares and Cygnus programs.
After launching to orbit atop the Antares rocket on Sept. 18, the first ever Cygnus cargo spacecraft chased the ISS and docked on Sept 29. Here is full scale, high fidelity mockup of Cygnus to give a feel for its size being similar to a small room. Credit: Ken Kremer (kenkremer.com)
On Expedition 27 in May 2011, NASA astronaut Cady Coleman participated in the Auroral Oval Spiral Top experiment. Credit: NASA
Wow! That was our reaction to seeing this picture (and others) of a light show aboard the International Space Station. After confirming with NASA that the images circulating lately on social media are real, we were directed to the Japan Aerospace Exploration Agency (JAXA), who co-ordinated this experiment.
The work is called “Auroral Oval Spiral Top” and was done in the Kibo module on May 12, 2011, JAXA said. This was the second version of the experiment, which initially ran April 30, 2009 during Expedition 19.
Spiral Top performed in 2009. The art project was an earlier version of the Auroral Oval Spiral Top experiment that was done in May 2011. Credit: NASA/JAXA
“Auroral Oval Spiral Top uses a spinning top that has arms illuminating with LED linear light sources and point light sources. Various movements of the spinning top floating in microgravity show aurora-like light traces,” JAXA stated on a web page about the experiment.
The project, JAXA added, is “designed to produce aurora-like luminescence traces using a spinning top with both linear and point light sources. In microgravity, the center of gravity of the spinning top continuously and randomly moves while it is spinning. Using the characteristics of the top in microgravity, the project tries to produce various light arts using its unexpected movements/spins, by changing attaching locations of its arms and weights.”
Takuro Osaka, a professor at the University of Tsukuba, was the principal investigator of this art project. What are your favorite experiments performed by astronauts in space? Let us know in the comments.
Another view of the Auroral Oval Spiral Top experiment. Credit: NASA
Sometimes you’ve just got to get away from it all. From your planet, your Solar System and your galaxy. If you’re looking to escape, you’ll need to know just what velocity it’ll take to break the surly bonds of gravity and punch the sky.
We record Astronomy Cast as a live Google+ Hangout on Air every Monday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch here on Universe Today or from the Astronomy Cast Google+ page.
Comet 2P/Encke as imaged by Damian Peach on October 12th. (Credit: D. Peach)
2013 may well go down as “The Year of the Comet.” After over a decade punctuated by only sporadic bright comets such as 17P/Holmes, C/2011 W3 Lovejoy and C/2006 P1 McNaught, we’ve already had two naked eye comets visible this year by way of C/2012 F6 Lemmon and C/2011 L4 PanSTARRS. And of course, all eyes are on Comet C/2012 S1 ISON as it plunges towards perihelion on U.S. Thanksgiving Day, November 28th.
But there’s an “old faithful” of comets that’s currently in our solar neighborhood, and worth checking out as well. Comet 2P/Encke (pronounced EN-key) currently shines at magnitude +7.9 and is crossing from the constellation Leo Minor into Leo this week. In fact, Encke is currently 2 magnitudes— over 6 times brighter than Comet ISON —and is currently the brightest comet in our skies. Encke is expected to top out at magnitude +7 right around perihelion towards the end of November. Encke will be a fine binocular object over the next month, and once the Moon passes Last Quarter phase on October 26th we’ll once again have a good three week window for pre-dawn comet hunting. Comet Encke made its closest pass of the Earth for this orbit on October 17th at 0.48 Astronomical Units (A.U.s) distant. This month sees its closest passage to the Earth since 2003, and the comet won’t pass closer until July 11th, 2030.
The orbital path of Comet 2P/Encke. (Credit: The NASA/JPL Solar System Dynamics Small-Body Database Browser).
This will be Comet Encke’s 62nd observed perihelion passage since its discovery by Pierre Méchain in 1786. Encke has the shortest orbit of any known periodic comet, at just 3.3 years. About every 33 years we get a favorable close pass of the comet, as last occurred in 1997, and will next occur in 2030.
But this year’s apparition of Comet Encke is especially favorable for northern hemisphere observers. This is due to its relatively high orbital inclination angle of 11.8 degrees and its passage through the morning skies from north of both the ecliptic and the celestial equator. Encke is about half an A.U. ahead of us in our orbit this month, crossing roughly perpendicular to our line of sight.
Note that Encke is also running nearly parallel to Comet ISON from our vantage point as they both make the plunge through the constellation Virgo into next month. Mark your calendars: both ISON and Encke will fit into a telescopic wide field of view around November 24th in the early dawn. Photo-op!
Here are some key dates to help you in your morning quest for Comet Encke over the next month:
-October 22nd: Crosses into the constellation Leo.
-October 24th: Passes near the +5.3 magnitude star 92 Leonis.
-October 25th: Passes near the +4.5 magnitude star 93 Leonis.
-October 27th: Passes briefly into the constellation Coma Berenices.
-October 29th: Passes near the +11th magnitude galaxy M98, and crosses into the constellation Virgo.
-October 30th: Passes near the +10th magnitude galaxy pair of M84 & M86.
The celestial path of Comet 2P/Encke from October 20th to 20 November 20th. Note that ISON is very near Encke on the final date. Click on the image to enlarge. (Created using Starry Night Education Software).
-November 2nd: Passes between the two +5th magnitude stars of 31 and 32 Virginis.
-November 3rd: A hybrid solar eclipse occurs across the Atlantic and central Africa. It may just be possible to spot comet Encke with binoculars during the brief moments of totality.
-November 4th: Passes near the +3.4 magnitude star Auva (Delta Virginis).
-November 7th: Crosses from north to south over the celestial equator.
-November 11th: Passes near the +5.7th star 80 Virginis.
-November 17th: The Moon reaches Full, and enters into the morning sky.
-November 18th: Passes 0.02 A.U. (just under 3 million kilometers, or 7.8 Earth-Moon distances) from the planet Mercury. A good chance for NASA’s Messenger spacecraft to perhaps snap a pic of the comet?
-November 19th: Passes 1.5 degrees from Mercury and crosses into the constellation Libra.
-November 20th: Crosses to the south of the ecliptic plane.
-November 21st: Reaches perihelion, at 0.33 AU from the Sun.
-November 24th: Comet Encke passes just 1.25 degrees from Comet ISON. Both will have a western elongation of 15 degrees from the Sun.
-November 26th: Passes near the +4.5 magnitude star Iota Librae and the +6th magnitude star 25 Librae.
-December 1st: Crosses into the constellation Scorpius.
-December 5th: Enters into view of SOHO’s LASCO C3 camera.
Note: “Passes near” on the above list indicates a passage of Comet Encke less than one angular degree (about twice the size of a Full Moon) from an interesting object, except where noted otherwise.
Binoculars are your best bet for catching sight of Comet 2P/Encke. For middle northern latitude observers, Comet Encke reaches an elevation above 20 degrees from the horizon about two hours before local sunrise. Keep in mind, Europe and the U.K. “fall back” an hour to Standard Time this coming weekend on October 27th, and most of North America follows suit on November 3rd, pushing the morning comet vigil back an hour as well.
Two other comets are both currently brighter than ISON and also merit searching for: Comet C/2013 R1 Lovejoy, at +8.7th magnitude in Canis Minor, and Comet C/2012 X1 LINEAR, currently also in Coma Berenices and undergoing a minor outburst at magnitude +8.5.
Be sure to check these celestial wonders out as we prepare for the “Main Event” of Comet ISON in November 2013!
Welcome, come in to the 324th Carnival of Space! The carnival is a community of space science and astronomy writers and bloggers, who submit their best work each week for your benefit. I’m Susie Murph, the newest member of the team at Universe Today, and I’m both thrilled and intimidated to be hosting this week’s Carnival for you, Hopefully I can present these articles with the fanfare that they deserve, so now, on to the stories!
First up, the Chandra X-Ray Observatory site began the week by celebrating Ada Lovelace Day. Ada Lovelace is widely considered to be the first computer programmer, and this day is celebrated as an occasion to promote women and their achievements in science, technology, engineering and math (aka, STEM), and Chandra does just that through their series of blogs Women in the High Energy Universe. Check out these posts about the amazing contributions that these women have made to both the observatory but also the fields of scientific endeavor.
Next, we have the Space Frontier Foundation discussing important point in the movie ‘Gravity,’ – the very real threat of orbital debris. (Spoiler Alert if you haven’t yet seen the movie!) Even the smallest pieces of debris can be deadly, because they can be moving at 27,350 kilometers per hour (17,000 miles per hour), and there are possibly hundreds of thousands of objects, most too small to track, in Earth orbit. However, there are ideas being presented to try to reduce the problems that this debris causes, and with improvements in technology, hopefully the kinds of disasters depicted in the movie never happen in real life.
The next two articles are from Brian Wang over at the Next Big Future blog.
First up, SpaceX reviews the September 29 test of the upgraded Falcon rocket , in which they completed several important milestones along the way to being certified for use by the U.S. Air Force for National Security Space missions, as well as the more difficult challenges of full recovery of the boost stage.
Next, as we celebrate Columbus’ voyage to the New World, Brian muses on what it would take to be the “Columbus of the Space Age.” He highlights the development of colonies that led to permanent populations, and gives some numbers on how we could quantify success for a modern-age explorer.
For the next article, we go over to the AARTScope Blog, for Peter Lake’s article about the discovery of Asteroid 2013 TV135 on October 8th. This asteroid was discovered after it missed the Earth by 6.7 million Km, and is predicted to return for a close approach to Earth in 2032. It has been initially listed as a “virtual impactor,” but with more observations, this categorization is likely to change.
Then we visit the Meridiani Journal for Paul Scott Anderson’s article on the upcoming mission to Mars from the Indian Space Research Organization (ISRO) on October 28. The spacecraft, dubbed Mangalyaan, is an upgraded version of Chandrayaan 1, and will study the Martian surface and atmosphere with its five payload instruments, including one that will sense the presence of methane.
And finally, we return here to Universe Today, to read Elizabeth Howell’s article about the discovery of the remains of a water-filled asteroid circling a dying white dwarf about 150 light years away from Earth. The discovery is considered very exciting, because it shows that the components that make life as we know it possible, such as liquid water on a rocky surface, are present in other solar systems.
That’s it for this week’s Carnival. See you all next time!
A March 2013 picture of the Shapley Supercluster from the European Space Agency's Planck observatory. ESA describes it as "the largest cosmic structure in the local Universe." Credit: ESA & Planck Collaboration / Rosat/ Digitised Sky Survey
With two days left before Planck switches off forever, the European Space Agency re-posted this beautiful image the telescope recently assisted in taking. It shows the Shapley Supercluster, which ESA describes as the biggest cosmic structure in our neighborhood.
First discovered in the 1930s by Harlow Shapley, a U.S. astronomer, the structure has more than 8,000 galaxies and a mass that is 10 million billion times that the mass of the Sun, ESA added. The blue parts are detections by Planck, and the Rosat satellite imaged the pink sections. Visible wavelengths shown in the picture come from the Digitised Sky Survey.
Today (Oct. 21), ESA will order Planck to run its thrusters to empty. After years hovering at a Lagrange point, the telescope will be put in a “parking orbit” to circle the sun, keeping it away from the Earth and moon for at least several centuries. The last command will be sent Oct. 23.
The crowdfunding campaign is off to a slow start, but the PHASST-1 telescope still has more than a month to reach its $88,816 (€65,000) goal of deploying telescopes devoted to searching for near-Earth asteroids.
The Potentially Hazardous Asteroid Search & Tracking Telescope, as the acronym stands for, will begin with two telescopes: an f/1 Baker-Nunn camera near Arequipa, Peru and a 50cm f/3.6 astrograph near Ager, Spain.
“Even though PHASTT-1 will have a large field of view compared to most telescopes (~5x) of a similar aperture, competing in the area of asteroid search is difficult due to a large number of teams doing similar work. Because of this, we are designing PHASTT-1 as not only a search telescope but also as a followup and characterization instrument — two key areas where we can make an impact,” the IndieGogo campaign page states.
“Follow-up observations are important as they help us refine the orbits of potentially hazardous objects and narrow the uncertainties around how close an asteroid will come to the Earth. Characterization of asteroids is also important as it helps us understand the physical properties of asteroids. This understanding critical if we want to know how to best deal with a ‘rogue’ asteroid that is on an impact course or if we just want to know which asteroids would make for interesting near-Earth exploration targets.”
The principles including astronomers, a technology consultant and a laser ranging specialist. You can read more technical details on the IndieGogo campaign page or the PHASTT-1 website. If they get the money they need, they aim to be operational by the middle of next year. The campaign completes Nov. 26.
Sunday’s Virtual Star Party felt like a reunion, with Mike Phillips, Gary Gonella, and Roy Salisbury supplying images and Scott Lewis co-hosting. We were joined by newcomer James McGee streaming a beautiful view of the Moon – when it wasn’t blocked by his apartment tower.
The Moon was just past full, so it commanded attention, but we still got a beautiful view of some fainter nebulae, galaxies and star clusters.
Astronomers: Mike Phillips, Gary Gonella, Roy Salisbury, James McGee
Hosts: Fraser Cain, Scott Lewis
Objects: The Moon, Pac Man Nebula, Eagle Nebula, Swan Nebula, Lagoon Nebula, Andromeda Galaxy, M15 globular cluster, Dumbbell Nebula, Veil Nebula and more.
We hold the Virtual Star Party every Sunday night when it gets dark on the West Coast of North America. You can watch it live on Universe Today, on Google+, or from the Universe Today YouTube Channel.
Another name for Mars is the Red Planet, and if you’ve ever seen it in the sky when the planet is bright and close to Earth, it appears like a bright red star. In Roman mythology, Mars was the god of war, so… think blood.
Even photos from spacecraft show that it’s a rusty red color. The hue comes from the fact that the surface is *actually* rusty, as in, it’s rich in iron oxide.
Iron left out in the rain and will get covered with rust as the oxygen in the air and water reacts with the iron in the metal to create a film of iron oxide.
Mars’ iron oxide would have formed a long time ago, when the planet had more liquid water. This rusty material was transported around the planet in dust clouds, covering everything in a layer of rust. In fact, there are dust storms on Mars today that can rise up and consume the entire planet, obscuring the entire surface from our view. That dust really gets around.
But if you look closely at the surface of Mars, you’ll see that it can actually be many different colours. Some regions appear bright orange, while others look more brown or even black. But if you average everything out, you get Mars’ familiar red colour.
If you dig down, like NASA’s Phoenix Lander did in 2008, you get below this oxidized layer to the rock and dirt beneath. You can see how the tracks from the Curiosity Rover get at this fresh material, just a few centimeters below the surface. It’s brown, not red.
And if you could stand on the surface of Mars and look around, what colour would the sky be? Fortunately, NASA’s Curiosity Rover is equipped with a full colour camera, and so we can see roughly what the human eye would see.
The sky on Mars is red too.
The sky here is blue because of Raleigh scattering, where blue photons of light are scattered around by the atmosphere, so they appear to come from all directions. But on Mars, the opposite thing happens. The dust in the atmosphere scatters the red photons, makes the sky appear red. We have something similar when there’s pollution or smoke in the air.
But here’s the strange part. On Mars, the sunsets appear blue. The dust absorbs and deflects the red light, so you see more of the blue photons streaming from the Sun. A sunset on Mars would be an amazing event to see with your own eyes. Let’s hope someone gets the chance to see it in the future.
We have written many articles about Mars on Universe Today. Here’s an article about a one-way, one-person trip to Mars, and here’s another about how scientists know the true color of planets like Mars.
Here are some nice color images captured of the surface of Mars from NASA’s Pathfinder mission, and here’s another explainer about why Mars is red from Slate Magazine.
