How Many Moons Does Venus Have?

A radar view of Venus taken by the Magellan spacecraft, with some gaps filled in by the Pioneer Venus orbiter. Credit: NASA/JPL

There are dozens upon dozens of moons in the Solar System, ranging from airless worlds like Earth’s Moon to those with an atmosphere (most notably, Saturn’s Titan). Jupiter and Saturn have many moons each, and even Mars has a couple of small asteroid-like ones. But what about Venus, the planet that for a while, astronomers thought about as Earth’s twin?

The answer is no moons at all. That’s right, Venus (and the planet Mercury) are the only two planets that don’t have a single natural moon orbiting them. Figuring out why is one question keeping astronomers busy as they study the Solar System.

Astronomers have three explanations about how planets get a moon or moons. Perhaps the moon was “captured” as it drifted by the planet, which is what some scientists think happened to Phobos and Deimos (near Mars). Maybe an object smashed into the planet and the fragments eventually coalesced into a moon, which is the leading theory for how Earth’s Moon came together. Or maybe moons arose from general accretion of matter as the solar system was formed, similar to how planets came together.

The International Space Station captured as it passed in front of the Moon on Dec. 6, 2013, as seen from Puerto Rico. Credit and copyright: Juan Gonzalez-Alicea.
The International Space Station captured as it passed in front of the Moon on Dec. 6, 2013, as seen from Puerto Rico. Credit and copyright: Juan Gonzalez-Alicea.

Considering the amount of stuff flying around the Solar System early in its history, it’s quite surprising to some astronomers that Venus does not have a moon today. Perhaps, though, it had one in the distant past. In 2006, California Institute of Technology researchers Alex Alemi and David Stevenson presented at the American Astronomical Society’s division of planetary sciences meeting and said Venus could have been smacked by a large rock at least twice. (You can read the abstract here.)

“Most likely, Venus was slammed early on and gained a moon from the resulting debris. The satellite slowly spiraled away from the planet, due to tidal interactions, much the way our Moon is still slowly creeping away from Earth,” Sky and Telescope wrote of the research.

“However, after only about 10 million years Venus suffered another tremendous blow, according to the models. The second impact was opposite from the first in that it ‘reversed the planet’s spin,’ says Alemi. Venus’s new direction of rotation caused the body of the planet to absorb the moon’s orbital energy via tides, rather than adding to the moon’s orbital energy as before. So the moon spiraled inward until it collided and merged with Venus in a dramatic, fatal encounter.”

Venus as photographed by the Pioneer spacecraft in 1978. Some exoplanets may suffer the same fate as this scorched world. Credit: NASA/JPL/Caltech
Venus as photographed by the Pioneer spacecraft in 1978. Some exoplanets may suffer the same fate as this scorched world. Credit: NASA/JPL/Caltech

There could be other explanations as well, however, which is part of why astronomers are so interested in revisiting this world. Figuring out the answer could teach us more about the solar system’s formation.

To learn more about Venus, check out these links:

Venus (NASA)
Venus Express (European Space Agency spacecraft currently at the planet)
Venus (Astronomy Cast)
Venus (Windows To The Universe)
Venus Crater Database (Lunar and Planetary Institute)
Magellan Mission to Venus (NASA)
Chasing Venus (Smithsonian)

Watch: New Documentary Follows the Hunt for Gravitational Waves

A newly released documentary brings you behind the scenes in the hunt for gravitational waves. The 20-minute film, called “LIGO, A Passion for Understanding,” follows the scientists working to create one of the most powerful scientific tools ever made: the Laser Interferometer Gravitational-Wave Observatories (LIGO). You can watch the documentary above.
Continue reading “Watch: New Documentary Follows the Hunt for Gravitational Waves”

Our Guide to the Bizarre April 29th Solar Eclipse

The 2013 partial eclipse rising over the Vehicle Assembly Building along the Florida Space Coast. This month's solar eclipse will offer comparable sunset views for eastern Australia. Photo by author.

Will anyone see next week’s solar eclipse? On April 29th, an annular solar eclipse occurs over a small D-shaped 500 kilometre wide region of Antarctica. This will be the second eclipse for 2014 — the first was the April 15th total lunar eclipse — and the first solar eclipse of the year, marking the end of the first eclipse season. 2014 has the minimum number of eclipses possible in one year, with four: two partial solars and two total lunars. This month’s solar eclipse is also a rarity in that it’s a non-central eclipse with one limit. That is, the center of the Moon’s shadow — known as the antumbra during an annular eclipse — will juuuust miss the Earth and instead pass scant kilometres above the Antarctic continent.

The "footprint" of the April 29th solar eclipse. Credit:
The “footprint” of the April 29th solar eclipse. Credit: Eclipse predictions by Fred Espenak, NASA/GSFC.

A solar eclipse is termed “non-central with one limit” when the center of the Moon’s umbra or antumbra just misses the Earth and grazes it on one edge. Jean Meeus and Fred Espenak note that out of 3,956 annular eclipses occurring from 2000 BCE to 3000 AD, only 68 (1.7%) are of the non-central variety. An annular eclipse occurs when the Moon is too distant to cover the disk of the Sun, resulting in a bright “annulus” or “ring-of-fire” eclipse. A fine example of just such an eclipse occurred over Australia last year on May 10th, 2013. An annular eclipse crossed the United States on May 10th, 1994 and will next be seen from the continental U.S. on October 14th 2023. But of course, we’ll see an end the “total solar eclipse drought” long before that, when a total solar eclipse crosses the U.S. on August 21st, 2017!

An animated .gif of the April 29th eclipse. Credit: NASA/GSFC/A.T. Sinclair.
An animated .gif of the April 29th eclipse. Credit: NASA/GSFC/A.T. Sinclair.

The “centrality” of a solar eclipse or how close a solar eclipse comes to crossing the central disk of the Earth is defined as its “gamma,” with 0 being a central eclipse, and 1 as the center of the Moon’s shadow passing 1 Earth radii away from central. All exclusively partial eclipses have a gamma greater than 1. The April 29th eclipse is also unique in that its gamma is very nearly 1.000… in fact, combing the 5,000 year catalog of eclipses reveals that no solar eclipse from a period of 2000 B.C. to 3000 A.D. comes closer to this value. The solar eclipses of October 3rd, 2043 and March 18th, 1950 are, however very similar in their geometry. Guy Ottewell notes in his 2014 Astronomical Calendar that the eclipses of August 29th, 1486 and January 8th, 2141 also come close to a gamma of 1.000. On the other end of the scale, the solar eclipse of July 11th 1991 had a gamma of nearly zero. This eclipse is part of saros series 148 and is member 21 of 75. This series began in 1653 and plays out until 2987 AD. This saros will also produce one more annular eclipse on May 9th 2032 before transitioning to a hybrid and then producing its first total solar eclipse on May 31st, 2068. But enough eclipse-geekery. Do not despair, as several southern Indian Ocean islands and all of Australia will still witness a fine partial solar eclipse from this event. Antarctica has the best circumstances as the Sun brushes the horizon, but again, the tiny sliver of “annularity” touches down over an uninhabited area between the Dumont d’Urville and Concordia  stations currently occupied by France… and it just misses both! And remember, its astronomical fall headed towards winter “down under,” another strike against anyone witnessing it from the polar continent. A scattering of islands in the southern Indian Ocean will see a 55% eclipsed Sun. Circumstances for Australia are slightly better, with Perth seeing a 55% eclipsed Sun and Sydney seeing a 50% partial eclipse.

The view of the eclipse from multiple locations across the Australian continent at 7:00 UT on April 29th. Created by the author using Stellarium.
The view of the eclipse from multiple locations across the Australian continent at 7:00 UT on April 29th. Created by the author using Stellarium.

Darwin,  Bali Indonesia and surrounding islands will see the Moon just nick the Sun and take a less than 20% “bite” out of it. Observers in Sydney and eastern Australia also take note: the eclipse occurs low to the horizon to the west at sunset, and will offer photographers the opportunity to grab the eclipse with foreground objects. Viewing a partial solar eclipse requires proper eye protection throughout all phases. The safest method to view a partial solar eclipse is via projection, and this can be done using a telescope (note that Schmidt-Cassegrain scopes are bad choice for this method, as they can heat up quickly!) or nothing more sophisticated than a spaghetti strainer to create hundreds of little “pinhole projectors.”

A simulation of the view that no one will see: the annular eclipse one kilometre above latitude 71S longitude 131E above the Antarctic. Created using Stellarium.
A simulation of the view that no one will see: the annular eclipse as seen hovering one kilometre above the Antarctic at latitude 71S longitude 131E . Created using Stellarium.

And although no human eyes may witness the annular portion of this eclipse, some orbiting automated ones just might. We ran some simulations using updated elements, and the European Space Agency’s Sun observing Proba-2 and the joint NASA/JAXA Hinode mission might just “thread the keyhole” and will witness a brief central eclipse for a few seconds on April 29th: And though there’ll be few webcasts of this remote eclipse, the ever-dependable Slooh is expected to carry the eclipse on April 29th. Planning an ad hoc broadcast of the eclipse? Let us know! As the eclipse draws near, we’ll be looking at the prospects for ISS transits and more. Follow us as @Astroguyz as we look at these and other possibilities and tell our usual “tales of the saros”. And although this event marks the end of eclipse season, its only one of two such spans for 2014… tune in this October, when North America will be treated to another total lunar eclipse on the 8th and a partial solar eclipse on the 23rd… more to come! Send in those eclipse pics to the Universe Today Flickr community… you just might find yourself featured in this space!

Stunning Original Drawing of the Latest SpaceX Launch

An original pencil illustration of the SpaceX CRS-3 Falcon 9 Dragon launch on April 18, 2014. Credit and copyright: Wendy Clark.

Here’s something you don’t see much anymore: an original pencil drawing of a launch. This drawing by Wendy Clark from the UK is reminiscent of the pre-spaceflight days, before we had actual images of launches, and just our dreams of spaceflight. This isn’t the first time Clark has drawn a launch (here’s an article we posted of her drawings of the MAVEN launch and the final space shuttle launch) but this one is almost a contrast in themes: the latest technology in launches from the upstart SpaceX team vs. an old-school, old fashioned, by-hand product.

For this drawing, she reiterated what she told us previously: “Don’t let anyone tell you drawing a rocket is easy!” Clark said on Flickr. “The Strongback was a complete dog of an object to draw, such a maze of engineering.”

She also captured the ‘dirty’ side of launches: “Dust and gravel being thrown up everywhere, and the lovely Falcon 9 rocket was a little grubby on lift-off and I’ve tried to reflect that in the drawing,” she said.

Thanks to Wendy Clark for sharing her work on Universe Today’s Flickr site. See more of her drawings and photography on her own Flickr page.

How Far Are The Planets From The Sun?

Artist's impression of the planets in our solar system, along with the Sun (at bottom). Credit: NASA

The eight planets in our solar system each occupy their own orbits around the Sun. They orbit the star in ellipses, which means their distance to the sun varies depending on where they are in their orbits. When they get closest to the Sun, it’s called perihelion, and when it’s farthest away, it’s called aphelion.

So to talk about how far the planets are from the sun is a difficult question, not only because their distances constantly change, but also because the spans are so immense — making it hard for a human to grasp. For this reason, astronomers often use a term called astronomical unit, representing the distance from the Earth to the Sun.

The table below (first created by Universe Today founder Fraser Cain in 2008) shows all the planets and their distance to the Sun, as well as how close these planets get to Earth.

Mercury:

Closest: 46 million km / 29 million miles (.307 AU)
Farthest: 70 million km / 43 million miles (.466 AU)
Average: 57 million km / 35 million miles (.387 AU)
Closest to Mercury from Earth: 77.3 million km / 48 million miles

Venus:

Closest: 107 million km / 66 million miles (.718 AU)
Farthest: 109 million km / 68 million miles (.728 AU)
Average: 108 million km / 67 million miles (.722 AU)
Closest to Venus from Earth: 40 million km / 25 million miles

The planet Venus, as imaged by the Magellan 10 mission. Credit: NASA/JPL
The planet Venus, as imaged by the Magellan 10 mission. Credit: NASA/JPL

Earth:

Closest: 147 million km / 91 million miles (.98 AU)
Farthest: 152 million km / 94 million miles (1.01 AU)
Average: 150 million km / 93 million miles (1 AU)

Mars:

Closest: 205 million km / 127 million miles (1.38 AU)
Farthest: 249 million km / 155 million miles (1.66 AU)
Average: 228 million km / 142 million miles (1.52 AU)
Closest to Mars from Earth: 55 million km / 34 million miles

Jupiter:

Closest: 741 million km /460 million miles (4.95 AU)
Farthest: 817 million km / 508 million miles (5.46 AU)
Average: 779 million km / 484 million miles (5.20 AU)
Closest to Jupiter from Earth: 588 million km / 346 million miles

Jupiter and Io. Image Credit: NASA/JPL
Artist’s impression of Jupiter and Io. Credit: NASA/JPL

Saturn:

Closest: 1.35 billion km / 839 million miles (9.05 AU)
Farthest: 1.51 billion km / 938 million miles (10.12 AU)
Average: 1.43 billion km / 889 million miles (9.58 AU)
Closest to Saturn from Earth: 1.2 billion km /746 million miles

Uranus:

Closest: 2.75 billion km / 1.71 billion miles (18.4 AU)
Farthest: 3.00 billion km / 1.86 billion miles (20.1 AU)
Average: 2.88 billion km / 1.79 billion miles (19.2 AU)
Closest to Uranus from Earth: 2.57 billion km / 1.6 billion miles

Neptune:

Closest: 4.45 billion km /2.77 billion miles (29.8 AU)
Farthest: 4.55 billion km / 2.83 billion miles (30.4 AU)
Average: 4.50 billion km / 2.8 billion miles (30.1 AU)
Closest to Neptune from Earth: 4.3 billion km / 2.7 billion miles

As a special bonus, we’ll include Pluto too, even though Pluto is not a planet anymore.

Uranus and Neptune, the Solar System’s ice giant planets. (Images from Wikipedia.)
Uranus and Neptune, the Solar System’s ice giant planets. Credit: Wikipedia Commons

Pluto:

Closest: 4.44 billion km / 2.76 billion miles (29.7 AU)
Farthest: 7.38 billion km / 4.59 billion miles (49.3 AU)
Average: 5.91 billion km / 3.67 billion miles (39.5 AU)
Closest to Pluto from Earth: 4.28 billion km / 2.66 billion miles

To learn more:

Online resources demonstrating the scale of the Solar System:

If The Moon Were Only A Pixel (Josh Worth Art & Design)
Scale Model Of Our Solar System (University of Manitoba)
Build A Solar System (Exploratorium)
Scale Solar System (Josh Wetenkamp)

Many cities and countries have also installed scale models of the Solar System, such as:

Voyage Scale Solar System (Washington, D.C.)
Sagan Planet Walk (Ithaca, N.Y.)
Maine Solar System Model
Sweden Solar System
Planet Walk (Munich, Germany)
The Solar System (Brittany, France; website in French only)
Solar System Drive (Australia)

Carnival of Space #350

Carnival of Space. Image by Jason Major.
Carnival of Space. Image by Jason Major.

This week’s Carnival of Space is hosted by Nicole Gugliucci at her Cosmoquest blog.

Click here to read Carnival of Space #350

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.

Video: Carolyn Porco Discusses Her Life at Saturn

Planetary scientists Carolyn Porco. Via NASA/JPL.

Space historian Andrew Chaikin sat down with planetary scientist Carolyn Porco, and she discusses how her career has ended up focusing on the Saturn system. I love how Porco relates how even she has been “blown away” by some of the imagery sent back by the missions — just like the rest of us! — saying she’s had to call members of her team several times to verify she wasn’t looking at computer simulations vs. real images.

Enjoy this candid interview of one of the leading planetary scientists of our day.


The Planets in Our Solar System in Order of Size

Planets in our Solar system size comparison. Largest to smallest are pictured left to right, top to bottom: Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars, Mercury. Via Wikimedia Commons.

If you’re interested in planets, the good news is there’s plenty of variety to choose from in our own Solar System. From the ringed beauty of Saturn, to the massive hulk of Jupiter, to the lead-melting temperatures on Venus, each planet in our solar system is unique — with its own environment and own story to tell about the history of our Solar System.

What also is amazing is the sheer size difference of planets. While humans think of Earth as a large planet, in reality it is dwarfed by the massive gas giants lurking at the outer edges of our Solar System. This article explores the planets in order of size, with a bit of context as to how they got that way.

A Short History of the Solar System:

No human was around 4.5 billion years ago when the Solar System was formed, so what we know about its birth comes from several sources: examining rocks on Earth and other places, looking at other solar systems in formation and doing computer models, among other methods. As more information comes in, some of our theories of the Solar System must change to suit the new evidence.

Today, scientists believe the Solar System began with a spinning gas and dust cloud. Gravitational attraction at its center eventually collapsed to form the Sun. Some theories say that the young Sun’s energy began pushing the lighter particles of gas away, while larger, more solid particles such as dust remained closer in.

Artist's conception of a solar system in formation. Credit: NASA/FUSE/Lynette Cook
Artist’s conception of a solar system in formation. Credit: NASA/FUSE/Lynette Cook

Over millions and millions of years, the gas and dust particles became attracted to each other by their mutual gravities and began to combine or crash. As larger balls of matter formed, they swept the smaller particles away and eventually cleared their orbits. That led to the birth of Earth and the other eight planets in our Solar System. Since much of the gas ended up in the outer parts of the system, this may explain why there are gas giants — although this presumption may not be true for other solar systems discovered in the universe.

Until the 1990s, scientists only knew of planets in our own Solar System and at that point accepted there were nine planets. As telescope technology improved, however, two things happened. Scientists discovered exoplanets, or planets that are outside of our solar system. This began with finding massive planets many times larger than Jupiter, and then eventually finding planets that are rocky — even a few that are close to Earth’s size itself.

The other change was finding worlds similar to Pluto, then considered the Solar System’s furthest planet, far out in our own Solar System. At first astronomers began treating these new worlds like planets, but as more information came in, the International Astronomical Union held a meeting to better figure out the definition.

Hubble image of Pluto and some of its moons, Charon, Nix and Hydra. Image Credit: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team
Hubble image of Pluto and some of its moons, Charon, Nix and Hydra. Image Credit: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team

The result was redefining Pluto and worlds like it as a dwarf planet. This is the current IAU planet definition:

“A celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit.”

Size of the Eight Planets:

According to NASA, this is the estimated radii of the eight planets in our solar system, in order of size. We also have included the radii sizes relative to Earth to help you picture them better.

  • Jupiter (69,911 km / 43,441 miles) – 1,120% the size of Earth
  • Saturn (58,232 km / 36,184 miles) – 945% the size of Earth
  • Uranus (25,362 km / 15,759 miles) – 400% the size of Earth
  • Neptune (24,622 km / 15,299 miles) – 388% the size of Earth
  • Earth (6,371 km / 3,959 miles)
  • Venus (6,052 km / 3,761 miles) – 95% the size of Earth
  • Mars (3,390 km / 2,460 miles) – 53% the size of Earth
  • Mercury (2,440 km / 1,516 miles) – 38% the size of Earth
Eight planets and a dwarf planet in our Solar System, approximately to scale. Pluto is a dwarf planet at far right. At far left is the Sun. The planets are, from left, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Credit: Lunar and Planetary Institute
Eight planets and a dwarf planet in our Solar System, approximately to scale. Pluto is a dwarf planet at far right. At far left is the Sun. The planets are, from left, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Credit: Lunar and Planetary Institute

Jupiter is the behemoth of the Solar System and is believed to be responsible for influencing the path of smaller objects that drift by its massive bulk. Sometimes it will send comets or asteroids into the inner solar system, and sometimes it will divert those away.

Saturn, most famous for its rings, also hosts dozens of moons — including Titan, which has its own atmosphere. Joining it in the outer solar system are Uranus and Neptune, which both have atmospheres of hydrogen, helium and methane. Uranus also rotates opposite to other planets in the solar system.

The inner planets include Venus (once considered Earth’s twin, at least until its hot surface was discovered); Mars (a planet where liquid water could have flowed in the past); Mercury (which despite being close to the sun, has ice at its poles) and Earth, the only planet known so far to have life.

To learn more about the Solar System, check out these resources:

Planets (NASA)
Solar System (USGS)
Exploring the Planets (National Air and Space Museum)
Windows to the Universe (National Earth Science Teachers Association)
Solar System (National Geographic, requires free registration)

Easter Sunday Space Station Rendezvous and Berthing for SpaceX Dragon Freighter Successful

SpaceX Dragon resupply spacecraft arrives for successful berthing and docking at the International Space Station on Easter Sunday morning April 20, 2014. Credit: NASA TV

The SpaceX 3 Dragon commercial cargo freighter successfully arrived at the International Space Station (ISS) on Easter Sunday morning, April 20, as planned and was deftly captured by Expedition 39 Commander Koichi Wakata at 7:15 a.m. EDT at the controls of the Canadian built robotic arm.

The next step due shortly is berthing of Dragon at the Earth facing port of the Harmony module at approximately 9:30 a.m. EDT.

Berthing was officially completed at 10:06 a.m. EDT while the massive complex was soaring 260 miles above Brazil.

This story is being updated as events unfold. The mission is the company’s third cargo delivery flight to the station.

The Dragon vehicle loaded with nearly 2.5 tons of science experiments and supplies moved ever so slowly closely to within grappling distance – dramatically backdropped with gorgeous and ever changing scenery of our Home Planet sliding below.

The million pound orbiting lab complex and free flying SpaceX Dragon were soaring some 260 miles above Egypt and the Nile River as the 57 foot long robotic arm grappled the resupply ship.

SpaceX Dragon resupply spacecraft arrives for berthing at the International Space Station on Easter Sunday morning April 20, 2014. Credit: NASA TV
SpaceX Dragon resupply spacecraft arrives for berthing at the International Space Station on Easter Sunday morning April 20, 2014. Credit: NASA TV

Dragon was approximately 30 feet (10 meters) away from the stations hull at the time of capture.

Wakata, of the Japan Aerospace Exploration Agency, was assisted by NASA astronaut Rick Mastracchio, while both were working from inside the 7 windowed Cupola robotics work station. Newly arrived NASA astronaut Steve Swanson observed the proceedings with a big smile.

“Congratulations to the entire ops team for the successful launch, rendezvous and capture of Dragon,” Wakata radioed mission control moments after the successful grapple.

“Great work catching the Dragon, enabling fantastic science,” radioed Capcom Steve Fisher from NASA Houston Mission Control.

SpaceX Dragon resupply spacecraft grappled by Canada robotic arm for berthing at the International Space Station on Easter Sunday morning April 20, 2014. Backdrop of Erath look like dried out river channel on Mars! Credit: NASA TV
SpaceX Dragon resupply spacecraft grappled by Canada robotic arm for berthing at the International Space Station on Easter Sunday morning April 20, 2014. Backdrop of Earth looks like dried out river channel on Mars! Credit: NASA TV

Cheers and celebrations erupted at SpaceX Mission Control at the firms headquarters in Hawthorne, Calif.

Dragon arrived this morning following Friday afternoons, Apr 18, spectacular blastoff from Cape Canaveral, Fla, atop an upgraded SpaceX Falcon 9 booster.

A two day orbital chase ensued with a series of critical engine burns targeting the ISS for Easter Sunday’s rendezvous and docking activities.

Rick Mastracchio was at the controls for the actual berthing and latching in place at Harmony with Dragon’s Common Berthing Mechanism (CBM).

NASA astronaut Steve Swanson, ISS Commander Koichi Wakata and NASA Astronaut Rick Mastracchio work inside the 7 windowed Cupola robotics work station module during Dragon berthing on Easter Sunday morning April 20, 2017. Credit: NASA TV
NASA astronaut Steve Swanson, ISS Commander Koichi Wakata and NASA Astronaut Rick Mastracchio work inside the 7 windowed Cupola robotics work station module during Dragon berthing on Easter Sunday morning April 20, 2017. Credit: NASA TV

The berthing process started at about 9:30 a.m. EDT.

4 latches were driven for 1st stage of capture. Followed by all 16 bolts and latches in total during second stage capture to firmly hold Dragon in place.

The crew and mission control concluded the berthing procedure at 10:06 a.m. EDT flying over Brazil.

The next step is for the crew to pressurize the vestibule connecting Dragon to station.

Hatch opening is set to take place on Monday morning.

It’s a busy week ahead for the six person international crew representing the US, Russia and Japan.

A Russian Progress departs on Wednesday followed by the 2 person US spacewalk to replace the failed MDM unit.

Dragon will remain attached to the station until May 18.

This story is being updated. Check back.

ISS Schematic showing modules and Dragon, Soyuz and Progress docking ports.  Credit: NASA TV
ISS Schematic showing modules and Dragon, Soyuz and Progress docking ports. Credit: NASA TV

The SpaceX-3 mission marks the company’s third operational resupply mission to the ISS under a $1.6 Billion contract with NASA to deliver 20,000 kg (44,000 pounds) of cargo to the ISS during a dozen Dragon cargo spacecraft flights through 2016.

There are over 150 science experiments loaded aboard the Dragon capsule for research to be conducted by the crews of ISS Expeditions 39 and 40.

This unmanned SpaceX mission dubbed CRS-3 mission will deliver some 5000 pounds of science experiments, a pair of hi tech legs for Robonaut 2, a high definition Earth observing imaging camera suite (HDEV), a laser optical communications experiment (OPALS) and essential gear, the VEGGIE lettuce growing experiment, spare parts, crew provisions, food, clothing and supplies to the six person crews living and working aboard the ISS soaring in low Earth orbit under NASA’s Commercial Resupply Services (CRS) contract.

NASA TV coverage of the Easter Sunday grappling process began at 5:45 a.m. EDT with berthing coverage beginning at 9:30 a.m. EDT: http://www.nasa.gov/ntv

Stay tuned here for Ken’s continuing SpaceX, Orbital Sciences, commercial space, Orion, Chang’e-3, LADEE, Mars rover, MAVEN, MOM and more planetary and human spaceflight news.

Screenshots by Rob v. Mackelenbergh.

Ken Kremer

Echoes of Chelyabinsk: Another Fireball Explodes Over Russia

Why does Russia seem to get so many bright meteors? Well at 6.6 million square miles it’s by far the largest country in the world plus, with dashboard-mounted cameras being so commonplace (partly to help combat insurance fraud) statistically it just makes sense that Russians would end up seeing more meteors, and then be able to share the experience with the rest of the world!

This is exactly what happened early this morning, April 19 (local time), when a bright fireball flashed in the skies over Murmansk, located on the Kola Peninsula in northwest Russia near the border of Finland. Luckily not nearly as large or powerful as the Chelyabinsk meteor event from February 2013, no sound or air blast from this fireball has been reported and nobody was injured. Details on the object aren’t yet known… it could be a meteor (most likely) or it could be re-entering space debris. The video above, some of which was captured by Alexandr Nesterov from his dashcam, shows the object dramatically lighting up the early morning sky.

One Russian astronomer suggests this bolide may have been part of the debris that results in the Lyrid meteor shower, which peaks on April 22-23. (Source: NBC)

Source: RT.com