Today Is the Winter Solstice – Here's What That Means

What’s A Solstice?

For many of us, December 21, 2016, marks this year’s Winter Solstice. But for plenty of others, it’s also the Summer Solstice. How can this be? What is actually unique about today from an astronomical sense? What is a solstice anyhow?

First, let’s be considerate of all people regardless of whether they live in the northern or southern hemisphere. Let’s refer to today’s event as the December solstice. We do this because while those of us that live in the northern hemisphere consider it to be Winter, our friends south of the equator are in the middle of their Summer. This, of course, is because the Earth is tilted on its axis–which means that for part of the year, the northern part of our planet is tilted towards the Sun (and thus receiving more exposure to solar radiation i.e. Summer), while the southern half is tilted away (less solar radiation i.e. Winter). The other half of the year, this is reversed. (If you live directly on the equator, you can call it whatever you want because you get to have Summer 365 days a year.)

A solstice occurs on the day when the planet’s hemisphere has its maximum (or minimum) amount of solar exposure (in December, it’s the northern; in June it’s the southern’s turn), which in turn gives us the longest and shortest days of the year. Contrast that to the equinoctes (yes, that really is the plural form of equinox), in which the length of day is equal to the length of night.

Now, you might have heard the solstices being referred to as the “First Day of Spring/Winter”, which if you live in a geographic area that has noticeable seasons you know this isn’t true. It would be more appropriate to consider a solstice as the middle of a season. Starting today, the daylight hours get longer in the northern hemisphere and shorter in the southern.

So where did the “First Day of Spring/Winter” idea come from?

 

I really don’t know.

If you find out, please let me know.

NASA's Penguin Patch

How An Imaginary Constellation Ended Up On An Official NASA Mission Patch

There are some great stories behind the patches that NASA issues for each of its missions, and the latest one I have learned about is no exception. I picked the story up from former astronaut, Rhea Seddon, via her newsletter and blog. (Seddon was featured in this previous post about NASA’s first female astronauts.)

 

STS-41-D - The Penguin Patch

STS-41-D Mission Patch – Source: NASA

STS-41-D was Space Shuttle Discovery’s first mission. Flying that mission were: Commander Henry W. Hartsfield Jr., Michael L. Coats, Richard M. Mullane, Steven A. Hawley, Judy Resnik, and Charles D. Walker. The launch was originally scheduled for June 26, 1984, but had to be aborted six seconds prior to launch. The mission finally launched two months later on August 30.

The patch bears the icon of the ship Discovery, one of the three ships in the fleet that founded Jamestown, Virginia. Around the outer edge are the last names of the crew members. Shuttle Discovery is shown with a large solar array rising from the payload bay. This array was part of the OAST-1 payload, a project to demonstrate the feasibility of large-scale solar arrays in space. In the background is a field containing twelve stars: symbolic of STS-41-D being NASA’s twelfth Shuttle flight.

But there’s a bit more to the story of those twelve stars. According to Seddon, Shuttle program patches had to be approved by the Director of Flight Crew Operations, a post held at that time by George Abbey. As the story goes, her husband, Robert “Hoot” Gibson (also an astronaut), had something to do with the design of the patch for STS-41-D. He presented it to Abbey, only to have it denied. Why? Because, Mr. Abbey said:

“There isn’t a penguin on it.”  

Hoot replied, “Why a penguin?”  

“Because there has never been one.”  

So, Hoot hurried back to the office in dismay to see what the crew could create.  He returned a few days later with a modified patch.  

“Where is the penguin?”  

“Here it is.  Those stars at the top are from the constellation Penguinus Australis.”  

Whether Abbey was convinced or not, the design was approved. The constellation, Penguinius Australis, of course, was a complete fabrication. 

STS-41-D Crew

The STS-41D mission crew: (seated left to right) Richard M. (Mike) Mullane, mission specialist; Steven A. Hawley, mission specialist; Henry W. Hartsfield, commander; and Michael L. (Mike) Coats, pilot. Standing in the rear are Charles D. Walker, payload specialist; and Judith A. (Judy) Resnik, mission specialist. – Source: NASA

The Penguin Patch joins a long list of interesting stories about some of NASA’s most overlooked gems. 

OSIRIS-REx – A Sample Return Mission To Asteroid Bennu

Tomorrow, September 8, 2016, NASA’s Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) is slated to launch from Cape Canaveral. It will take two years for the craft to reach its destination, the asteroid Bennu, where it will collect a sample and return it to Earth. The mission is a partnership between the University of Arizona, NASA’s Goddard Space Flight Center and the Lockheed Martin Company.

OSIRIS-REx Mission Logo - Source: NASA

OSIRIS-REx Mission Logo – Source: NASA

The OSIRIS-REx mission will send a spacecraft to 101955 Bennu (hereafter referred to simply as Bennu), a potentially Earth-impacting asteroid with an average diameter of 492 meters (1,614 ft; 0.306 mi). The mission has five primary science objectives (the mission, OSIRIS-REx, takes its name from an acronym of these objectives):

• Origins: Return and analyze a pristine carbon rich
asteroid sample
• Spectral Interpretation: Provide ground truth or
direct observations for telescopic data of the
entire asteroid population
• Resource Identification: Map the chemistry and
mineralogy of a primitive carbon rich asteroid
• Security: Measure the effect of sunlight on the
orbit of a small asteroid, known as the Yarkovsky
effect—the slight push created when the asteroid
absorbs sunlight and re-emits that energy as heat
• Regolith Explorer: Document the regolith (layer
of loose, outer material) at the sampling site at
scales down to the sub-centimeter

The $800-million (not including launch vehicle costs) mission budget will support the program through the return of the sample capsule in 2023, and two years of analysis and cataloging.

The spacecraft, built by Lockheed Martin Space Systems Company at its facility near Denver, Colorado, is 6.2 meters (20.25 feet) long with its solar arrays deployed, and 2.43 meters (8 feet) by 2.43 meters (8 feet) wide. It’s 3.15 meters (10.33 feet) tall. The total weight of the spacecraft, including fuel, is 2,110 kilograms (4,650 pounds)–unfueled, it weighs 880 kilograms (1,940 pounds). It boasts two solar panel generators that produce between 1,226 watts and 3,000 watts of electrical power depending on its distance from the Sun.

Following its September 8, 2016 launch, the spacecraft will undergo an Earth flyby in September of 2017, before arriving at Bennu in August of 2018. According to the program fact sheet, “[t]he spacecraft will begin a detailed survey of Bennu two months after slowing to encounter Bennu. The process will last over a year, and, as part of it, OSIRIS-REx will map potential sample sites. The sample is expected to occur in July of 2020, when the craft’s sampling arm will contact Bennu’s surface, release a burst of nitrogen gas, and capture the resulting particles. It’s expected to collect up between 60 grams (2 ounces) and 2 kilograms (4.4 pounds). After the sample is taken, OSIRIS-REx’s Sample Return Capsule will wait for a proper alignment with Earth for the return trip home. The sample is expected to re-enter Earth’s atmosphere on September 24, 2023–just over seven years after its 2016 launch.

OSIRIS-REx Survey Animation - Source: University of Arizona

OSIRIS-REx Survey Animation – Source: University of Arizona

Why Bennu?

In addition to Bennu being a good candidate to study the building blocks of our solar system (“An uncontaminated asteroid sample from a known source would enable precise analyses, revolutionizing our understanding of the early solar system, and cannot be duplicated by spacecraft-based instruments or by studying meteorites“), I mentioned above that Bennu is a “potentially Earth-impacting asteroid”. The chances of Bennu impacting Earth are slim–0.037%, and that’s not even until the period between 2175 – 2196–but it still serves as a good model to use to understand both the hazards and resources that coincide with near-Earth asteroids.

Here’s to a successful launch tomorrow, and a successful mission over the next seven years!

Godspeed OSIRIS-REx! Ad Astra!

Want more information on the mission? The NASA Press Kit has a wealth of information.

Yesterday Was A Big Day For SpaceX

Yesterday was a big day for Elon Musk and his space launch services company SpaceX. On April 9, 2016, SpaceX launched its Falcon 9 rocket from Cape Canaveral. The rocket was topped with the company’s Dragon capsule, filled with 7,000 pounds of supplies destined for the International Space Station. Included in the payload was the 3,100 pound Bigelow Expandable Activity Module (BEAM), Bigelow Aerospace’s attempt to demonstrate its expandable space habitats.

SpaceX CRS-8 Mission Patch

SpaceX CRS-8 Mission Patch – Source: SpaceX

The highlight of the mission, designated CRS-8, was SpaceX’s first successful landing of its Falcon 9 rocket on a droneship (christened “Of Course I Still Love You”) in the Atlantic Ocean. This feat is something SpaceX had tried and failed four times previously. SpaceX has successfully landed its Falcon 9 on land, but that challenge paled in comparison to a landing on a barge being tossed around by Atlantic currents.

SpaceX has put a huge emphasis on making its programs efficient and reusable. Their hope is that their methods will drive down the costs of putting people and equipment into orbit and beyond, and make launches much more common. Friday’s successful landing of the Falcon 9 was a huge step in that direction.

All in all, Friday’s success should serve as an important milestone in space exploration. It also highlights the ever increasing transfer of space access from governments to commercial industries.

Check out the amazing video below, of the Falcon 9 landing on ‘Of Course I Still Love You’.

Unreal.

Dragon will arrive at the ISS tomorrow, April 10.

Wordless Wednesday 27 – Helical Antenna Operators

Ground telemetering helical antenna. 2/15/1951

Ground telemetering helical antenna, from 2/15/1951 – Source: NASA/JPL


Wordless Wednesday: An occasional feature in which interesting images are showcased with nothing more than an image caption. These images often become the subject of future full-length posts.

Tour the International Space Station

The International Space Station is featured in this 2010 image photographed by an STS-132 crew member on board the Space Shuttle Atlantis after the station and shuttle began their post-undocking relative separation.

The International Space Station is featured in this 2010 image photographed by an STS-132 crew member on board the Space Shuttle Atlantis after the station and shuttle began their post-undocking relative separation. – Source: NASA

Have you ever wanted to visit the International Space Station? Without a whole lot of education, extreme determination, and a fair helping of luck, chances are you won’t be visiting it in-person anytime soon. But, that doesn’t mean you can’t take a virtual tour of humanity’s only off-planet home. With the multimedia below, get a feel for what life aboard the International Space Station is like. No spacesuit required.

ESA Panoramas

The European Space Agency (ESA) put together the following 360° panorama of the ISS’s Russian Zvezda module. Notice how there are work surfaces that could only function in a weightless environment. For example, pan straight up towards the ‘ceiling’. (Note: After you hit play, you’ll want to click the full-screen button in the bottom right corner of the video.)

This 360° panorama allows you to explore the International Space Station’s third module, Zvezda. Launched on 12 July 2000, the Russian module supplies life support for the Station and crewquarters. All five of Europe’s Automated Transfer Vehicles docked with the module.

The images to create this view were taken by ESA astronaut Samantha Cristoforetti during her Futura mission in 2015; the cosmonaut in the picture is Gennady Padalka.

Two other views like this are also available on YouTube thanks to the ESA. Check out the Zarya and Unity modules as well.

ESA Interactive Tour

Next up, we have an interactive presentation that you’re going to have to go see for yourself. Check out this interactive tour of nearly the entire ISS. Turn on the map overlay and you can jump to individual sections of the station, or just tour it manually by clicking on the blue arrows. (I managed to get myself lost!) Video clips are interspersed throughout the tour for a more-detailed look.

Just before ESA astronaut Samantha Cristoforetti left the International Space Station after 199 days, she took up to 15 pictures inside each module. Now, the images have been stitched together to create this interactive panorama.

These panoramas offer a snapshot of the International Space Station as it was in June 2015, after moving the Leonardo storage module to a new location.

Wasn’t that cool?

Commander Sunita Williams Tour

One more for today. While not interactive like the other two, this video is one of my favorite tours of the ISS.

In her final days as Commander of the International Space Station, Sunita Williams of NASA recorded an extensive tour of the orbital laboratory and downlinked the video on Nov. 18, just hours before she, cosmonaut Yuri Malenchenko and Flight Engineer Aki Hoshide of the Japan Aerospace Exploration Agency departed in their Soyuz TMA-25A spacecraft for a landing on the steppe of Kazakhstan. The tour includes scenes of each of the station’s modules and research facilities with a running narrative by Williams of the work that has taken place and which is ongoing aboard the orbital outpost.

 

The 2012 video is somewhat long, 25 minutes, but by the end of it you find yourself wishing it would go on longer. Commander Sunita Williams takes us all throughout the space station while demonstrating various features and functions. I especially enjoyed her taking us inside the docked Soyuz capsule that she would be dropping back to Earth in, mere hours after creating this video.

Book Review: Packing For Mars by Mary Roach

Packing For Mars cover

  • Title: Packing For Mars
  • Author: Mary Roach
  • Printed Pages: 334
  • Publish Year: August 2nd 2010 (W. W. Norton & Company)
  • Recommended For: People that want all of the dirty details about spaceflight that NASA tends not to advertise, those that enjoy Mary Roach’s humor and wit, and anyone who wants to find out just how ‘wrong’ some of that ‘Right Stuff’ was.

First Lines: “To the rocket scientist, you are a problem. You are the most irritating piece of machinery he or she will ever have to deal with. You and your fluctuation metabolism, your puny memory, your frame that comes in a million different configurations.”

Review:

I’ve read this book twice now. I read it when it was released in 2010.  I wasn’t familiar with Mary Roach at the time, but I was particularly interested in the history of spaceflight at the time. While waiting to board a few-hour flight, I saw this book in one of the airport book shops. I read the cover and knew I had to read it on the flight. My new Kindle was a novelty to me at the time, so I decided I would purchase the electronic version to read on the plane. I ran into snags trying to get my Kindle to connect to the airport’s WiFi. While in line to board, I figured out a way to turn my smartphone into a hotspot, connect the Kindle to that connection, and then download the book. It was a close call, but ultimately I had my book.

Packing For Mars kept me entertained for the entire 3-hour flight. My fellow aisle mates had to have been curious about what I thought was so funny because I couldn’t help cracking up at Roach’s witty humor. Before I knew it, the captain was already announcing that we’d be landing soon.

Then, I read it again in 2016 in a cabin in the woods, in Alaska, in the winter. I enjoyed the book even more the second time and picked up on things that I didn’t catch the first time. My knowledge of the US space program is much greater than it was the first time I read this book, and this helped me make mental connections that weren’t apparent the first time. In a sense, I’m saying that this is a book that grows with you.

Mary Roach covers nearly everything in her book. She highlights just how unusual an environment outer space is to the human body. This book reveals nearly everything you could imagine. Serious critical attention is spent on how one goes to the bathroom in space, how sex would work (speculating on whether some might already know the answer to this), how you eat, how you sleep, the risks, the rewards, and the awkwardness.

Roach takes our hero astronauts and cosmonauts and reveals a side of them that’s often overlooked: the fact that they don’t have superpowers, they’re people just like you and me.

One thing I couldn’t help but laughing at after reading this book is that one of the differences between me and an astronaut is that I wear diapers way less than they do!

I’m going to avoid trying to list everything the book covers, and instead I just want to encourage you to check it out for yourself. You don’t even have to be a space-nerd like myself to appreciate this book; it will entertain virtually anyone.

Selected Lines:

As when astronaut Mike Mullane was asked by a NASA psychiatrist what epitaph he’d like to have on his gravestone. Mullane answered, “A loving husband and devoted father,” though in reality, he jokes in Riding Rockets, “I would have sold my wife and children into slavery for a ride into space.”


Among the 106 items left on the moon’s surface by Neil Armstrong and Buzz Aldrin are four urine collection assemblies—two large and two small. Who wore which remains a matter of conjecture.


If it’s cordless, fireproof, lightweight and strong, miniaturized, or automated, chances are good NASA has had a hand in the technology. We are talking trash compactors, bulletproof vests, high-speed wireless data transfer, implantable heart monitors, cordless power tools, artificial limbs, dustbusters, sports bras, solar panels, invisible braces, computerized insulin pumps, fire-fighters’ masks.


 

 

My Rating: I have no problem giving this book a 5/5, for making me laugh through turbulence on an airplane, for satisfying some of my greatest curiosities about space, and for making me see my space heroes in a new light: still as amazing as they were when I was a kid, but now with a greater sense of kinship.

You can snag a copy of the book via the link below, and I really hope you will.

Happy March Equinox: An Explanation

March Equinox graphic

Solstice and equinox diagram, showing the March equinox

Image Credit: NASA

Today is the March Equinox. You’ve probably already heard it a few times today; people running around proclaiming with utmost exuberance how today is the first day of Spring. After the long winters that some of us endure, the arrival of Spring is welcome news. But what is really going on today? After all, where I live it still feels like the middle of Winter, but flowers were already blooming on a trip I took to California a couple of weeks ago1. If we based “The First Day of Spring” on climate patterns, regions across the globe would be recognizing a wide variety of days throughout the year.

When someone says today is the first day of Spring, what they really mean (whether they know it or not) is that today represents an equinox; specifically, the March Equinox.2 On Earth, an equinox is the point in its orbit around the Sun when both hemispheres are equally illuminated; our tilted Earth lines up to a point in which the Sun passes directly over the equator. This happens twice a year, on the March and September equinoctes (which I learned today is the proper plural form of the word equinox).

Contrary to popular belief, the day of the equinox does not represent the day where daylight and darkness are equal. You can thank geometry, the atmosphere, and the Sun’s angular diameter to cause that equality to happen at different times geographically. What today does mean though, is that the equinoctes are the only two days in which the Sun rises due-East and sets due-West, and which the Sun would pass directly overhead from an observer on the equator.

One other very important thing that you must know if you don’t learn anything else today. Way too many people believe that the equinoctes are the only day of the year that an egg can be balanced on its end. While its true that on the equinox an egg can be balanced, it’s also true of every other day of the year; it makes no difference!

There are other times during the year (read: our orbit around the Sun) that we recognize Earth residing at a special place.  There’s Perihelion (which we went over in January) and Aphelion, and then the widely-celebrated solstices; but I’ll save that for another time.

Happy March Equinox!


This article originally posted on March 20, 2012.

  1. In fact, while it may have still been Winter to the San Diegans giving me quizzical looks for swimming in the ocean without a wet suit, to an Alaskan like myself it felt like an unusually warm Summer’s day!
  2. What about them being called the Spring  and Fall (or their Latin names, Vernal and Autumnal) equinoctes? Well, that wasn’t exactly fair to those in the Southern Hemisphere, whose seasons are opposite those in the Northern Hemisphere.

Wordless Wednesday 26 – M2-F1 In Tow

M2-F1 lifting body in tow

M2-F1 lifting body in tow – Credit: NASA


Wordless Wednesday: An occasional feature in which interesting images are showcased with nothing more than an image caption. These images often become the subject of future full-length posts.

ExoMars: Meet ESA's Next Robotic Mars Explorer

Artist's impression depicting the separation of the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, from the Trace Gas Orbiter, and heading for Mars.

Artist’s impression depicting the separation of the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, from the Trace Gas Orbiter, and heading for Mars. – Source: ESA/ATG medialab

On Monday, March 14, 2016, the European Space Agency’s (ESA) robotic explorer, ExoMars, is slated to launch from the Baikonur Cosmodrome in Kazakhstan. Seven months later, ExoMars will arrive at the red planet and begin a number of scientific investigations that were designed to help determine whether live ever existed on Mars.

ExoMars Programme

ESA is establishing ExoMars as a two-part program (they spell it programme). The first is the part that’s launching in a few days: an orbiter with an entry, descent, and landing module. The second component is scheduled for a 2018 launch and will include a rover. Roscosmos, the Russian space agency, is a partner with the ESA for the entire program.

The goal of the program is to “demonstrate a number of essential flight and in-situ enabling technologies that are necessary for future exploration missions, such as an international Mars Sample Return mission” and to operate “a number of important scientific investigations”. The latter investigations are designed to search for both past and present life on Mars, understand how the water and geochemical environment varies across the planet, and sample Mars’s atmosphere.

This year’s mission includes an orbiter that will sample trace gases, as well as a landing module that study the environment at its landing site (it will be stationary once it lands). The lander even has a name: Schiaparelli. The name comes from the 17th century Italian astronomer Giovanni Virginio Schiaparelli.

Part of the entire program are a number of assessment tools to evaluate the performance of the various components of the mission, to aid in the design of future missions.

The planned 2018 mission will include a rover with a two-meter drill that will allow access deeper into the Martian soil than we have been able to get to before.

ExoMars 2016 in the Proton-M launcher at the launch pad in Baikonur, Kazakhstan.

ExoMars 2016 in the Proton-M launcher at the launch pad in Baikonur, Kazakhstan.
Credit: ESA – B. Bethge

You can watch a livestream of the video from this page: Watch ExoMars Launch. Coverage begins at 08:30 GMT (04:30 am Eastern Daylight Time) on March 14, with launch scheduled at 09:31 GMT (05:30 am Eastern Daylight Time).

You can also get updates on the mission from the ESA_ExoMars Twitter feed:

Arrival at Mars is expected on October 19, 2016. For more information on the mission, check out ESA’s mission site.