Juno @ Jupiter

Something well worth watching ; something never before seen by human eyes . . .

http://www.nasa.gov/press-release/nasas-juno-spacecraft-in-orbit-around-mighty-jupiter

Thanks to the scientists, engineers, technicians, mathematicians, and others at NASA.

Enjoy!

Posted in Astronomy, Miscellaneous Musings, NASA | Leave a comment

Orion Journey to Mars, Part 3

JTM LARGE

All Photos & Illustrations Credit: NASA unless noted otherwise.

26 November 2015

I think the previous post about the James Web Space Telescope (JWST) was a worthwhile detour from The Journey to Mars, and here we are back on track, so let’s continue the journey . . .

The photo, below, shows NASA employees at Kennedy Space Center in Florida viewing the Orion Multi Purpose Crew Vehicle (MPCV) with the Heat Shield and Back Shell removed. The pristine condition suggests that Exploration Flight Test-1 (EFT-1) was a success (which, indeed, it was).

Orion after EFT-1 backshell removed
The photo, below, shows the heat shield returned to the lab for inspection after EFT-1.

Orion Chared Heat Shield

It has been almost a year since Orion successfully completed the Exploration Flight Test-1 in early December 2014. The NASA Orion Engineering Team has been developing improvements for the Heat Shield based upon data collected from the many pressure and temperature sensors on Orion during EFT-1.

The photo, below, shows the heat shield being inspected before it was attached to Orion during assembly, BEFORE the test . . .

HS Framework
The titanium framework visible in the photo provides strength and rigidity. The good news is that the data collected during flight and reentry will allow the framework to be “tweaked” so that it will weigh less and cost less. Notice the smooth orange color on the body of the shield – that is the Avcoat ablative material that carries heat away from Orion during reentry into the atmosphere. While the ablative material did meet the objectives for EFT-1, there were concerns following the detailed investigation after the test that the monolithic coating of ablative material would not suffice for future, more demanding flight and reentry conditions.

In any event, the engineering team decided to change the physical characteristics by using individual Avcoat filled honeycombed tiles instead of the monolithic coating used for EFT-1.

HS new tiles

The photo, above, shows some tiles attached to the heat shield that will be used for the next test, Exploration Mission Test-1 (EMT-1). EMT-1 will keep Orion in cislunar space for almost a month and the reentry speed will be about 36,000 feet per second (about 6,000 feet per second faster than EFT-1) and temperature increases exponentially with increased speed.

This “Design/Build/Test/Improve, then Test again” approach that is being used for the Orion Heat Shield is typical for everything that NASA does. Space travel is a very dangerous business and PERFECTION must be the goal. “Good enough” simply isn’t. “Too much” is just about right when it comes to safety and performance for space travel.

Having said all that, it is time to take a closer look at the Orion Service Module that provides propulsion, electricity, water, and air for the Orion Multi Purpose Crew Vehicle (MPCV) . . .

SM circular solar panels


The service module illustrated above is expendable and does not return to Earth with the Crew module.

The Service Module solar panels provide electrical power for the Orion spacecraft when it is operating independently from the SLS rocket structure.

I don’t know whether the circular or rectangular solar panels will be used for the circumlunar test, which is planned for about two years hence.

The illustration, below, shows a Service Module with rectangular solar panels.

Orion and SM rectangular solar panels
That’s it, for now. The next post is not quite ready for prime time yet, but I hope to have it finished soon.

Meanwhile, keep looking up, there’s lots to see up there on clear nights. Heck, you can even see the Space Station with the naked eye, if you know where (and when) to look. How do you find out where and when to look ?? Easy – – just get daily email from NASA that tells you all about it. Check it out at:

http://www.nasa.gov/vision/space/travelinginspace/f_skywatch.html

 

Posted in Journey to Mars, Miscellaneous Musings | Tagged , , , , | 1 Comment

James Web Space Telescope

25 November 2015

A quick brake from The Voyage to Mars to show what’s going on right now regarding the construction of the James Web Space Telescope (JWST) which is scheduled to be launched in 2018 as a replacement for the Hubble Space Telescope . . .

JWST mirror in place BIG

The photo, above, shows engineers and technicians working to assemble the James Web Space Telescope (JWST) in a clean room at the NASA Goddard Space Flight Center, Greenbelt, Maryland.

The hexagonal mirrors are being put in place on the framework of the JWST.

Shown, below: Preparation to attach the first of 18 hexagonal mirrors, each 4.2 feet (1.2 meters) across and weighing 88 pounds (40 kg).

JWST Prepare for Mirror
Each mirror must be carefully guided into place, as shown below . . .

JWST Hex Mirror
The mirrors are made of Beryllium which is being used because it is lightweight and has the ability to retain its shape in space temperatures which will vary from -406 to -343 degrees, F.

Hope you have enjoyed this little pause in The Voyage to Mars.

Have a wonderful holiday(s) season, starting with Thanksgiving and continuing through “new year’s day”, including Isaac Newton’s birthday which we celebrate on December 25.

Posted in Astronomy | Tagged , , | 1 Comment

Orion Journey to Mars, Part 2

JTM LARGE

 

All Photos & Illustrations Credit: NASA unless noted otherwise.

21 November 2015

As you can see in the illustration below, the Multi Purpose Crew Vehicle (MPCV), Orion, is quite a bit larger than the crew module used for the Apollo missions to the moon . . .

Orion over Apollo.png
Apollo was intended to carry crew of 3. The Orion Multi Purpose Crew Vehicle (MPCV) can carry up to 6 crew members to the International Space Station (ISS) and 4 crew members on deep space missions such as The Voyage to Mars . . .

Orion 4 or 6 crew.png

For deep space missions Orion will be attached to a Deep Space Habitat with sleeping quarters, a galley, and work area for research and communications. There are a number of configurations for habitat modules in early phases of design so at this time it is uncertain which design will be used.  An Illustration of what the Habitat might look like is shown below.

Deep Space Habitat Module

There are also habitats being designed that are intended for the surface of Mars, and that is a topic for another day.

Meanwhile, back to the MPCV for more detail . . .

The cutaway drawing shown below illustrates the overall structure including the pressure vessel and the ceramic back shell.

Orion annotated cutaway

Orion has a multitude of parts that must be assembled. Since Orion is the “control deck” for the whole SLS rocket, there is wiring that must be put in place for connecting to the various displays and control panels inside the pressure vessel shown on the left-hand side of the illustration, above.

The photo, below,shows technicians attaching wiring harnesses to the pressure vessel.

Pressure Vessel (1)

As you can see in the photo, above, there is quite a bit of space between the pressure vessel and the back shell that can be used for storage (see photo below).

naked Orion 2

Notice that the heat shield has not yet been attached to Orion in the photo above. The black membrane on the bottom of the module protects the crew from harmful gases that might enter the pressure vessel from the Service Module.

The back shell that fits over the pressure vessel is made of ceramic tiles that are attached individually by hand. These tiles can be thought of as “armor plating” and protect Orion and the crew from heat of reentry into the atmosphere of Earth or Mars, radiation, and collisions with small “space junk” as Orion passes through cislunar space on its way to deep space destinations such as an asteroid or Mars.

The photo, below, shows one of the ceramic back shell tiles being put in place . . .

Orion Placing a tile

 

The photo, below, shows recovery from the Pacific after returning from a distance of 3,600 miles in space during Orion’s first live test, known as Orion Exploration Test-1 (EFT-1). Notice that the heat shield shows some evidence of char, but the protective tiles on the back shell show minimal discoloring or damage.

Orion 2 recovery divers

The two U.S. Navy divers have already attached the recovery harness under the heat shield and Orion is ready to go to the recovery ship – see below . . .

Orion to Recovery Ship USS Anchorage

The photo, below, shows Orion safely in the “well” of recovery ship USS Anchorage.

Orion in %22well%22 of recovery ship

There is, of course, much more to the story of Orion’s continued development following the successful completion of its first live test, and we (YOU & I) take a look at more details in the next post.

Until then, take care and keep looking up, especially at night when there are countless wonders to behold “up there”.

Posted in Journey to Mars | Tagged , , , , , , | 1 Comment

Orion Journey to Mars, Part 1

JTM LARGE
All Photos & Illustrations Credit: NASA unless noted otherwise.

One day, sometime in the 2030s, if all goes according to plan, four astronauts will ride an Orion Multi Purpose Crew Vehicle (MPCV) to the surface of Mars after having lived and worked in a Deep Space Habitat that has been attached to the Orion for the previous nine months, or so.

What are these astronauts doing right now, today, here on Earth? (You might want to know.)

They are preparing for the Journey to Mars. Some of them may know that’s what they are doing some may not, but every one of them is creating their own “Right Stuff” that will qualify them for the Journey to Mars. In addition to meeting the NASA Basic Qualification Requirements (see below) the Mars bound astronauts will have completed multiple missions into cislunar space and may have landed on an asteroid, completed a round-trip to orbit Mars and return to Earth not having landed on the surface of Mars.

What, exactly, is the RIGHT STUFF ? NASAs requirements as of 15 November 2015 are . . .

 

NASA Basic Qualification Requirements (Copied from the NASA website.)

[[ Applicants must meet the following minimum requirements before submitting an application.

[] Bachelor’s degree from an accredited institution in engineering, biological science, physical science or mathematics.

[] Degree must be followed by at least 3 years of related, progressively responsible, professional experience or at least 1,000 pilot-in-command time in jet aircraft. An advanced degree is desirable and may be substituted for experience as follows: master’s degree = 1 year of experience, doctoral degree = 3 years of experience.

[] Teaching experience, including experience at the K – 12 levels, is considered to be qualifying experience for the Astronaut Candidate position; provided degree is in a Science, Engineering, or Mathematics field.

[] Ability to pass the NASA Astronaut physical, which includes the following specific requirements:

[] Distant and near visual acuity: Must be correctable to 20/20, each eye.

The refractive surgical procedures of the eye, PRK and LASIK, are allowed, providing at least 1 year has passed since the date of the procedure with no permanent adverse after effects. For those applicants under final consideration, an operative report on the surgical procedure will be requested.

[] Blood pressure not to exceed 140/90 measured in a sitting position

[] Standing height between 62 and 75 inches. ]]

 

As you can see in the illustration below, there are 4 parts that make up then payload for an SLS rocket that will take astronauts to Mars. Rather than putting all 4 parts into a single post, we (YOU & I) will look at them one at a time to delve into the details of each. The remainder of the SLS rocket is mostly fuel and rocket engines and we will take a closer look at them, later.

Spacraft Adaptet thru Abort System


The photo, below, shows Orion Multi Purpose Crew Vehicle (MPVC) ready for its first “live” test in December 2014 . . .

Orion ready for EFT-1
In December 1014 the Orion spacecraft successfully completed initial “live” testing . . .

Orion's First Flight 2.png
After landing in then Pacific about 600 miles off the California coast Orion was recovered and tested to gather information that will help to correct any problems before the next test.

Recovery crew in boat


As you can see in the photo below, Orion’s heat shield was charred even though the return speed of about 20,000 mph is far below speed of reentry after future missions into deep space when the return speed will be almost 30,000 mph and temperatures will rise to 5,ooo degrees.

Orion Chared Heat Shield
In my next post we (YOU & I) will take a closer look into the Orion MPCV  including the attached Servise Module. The Service module was not included in the initial test described above.

Posted in Journey to Mars | Tagged , | 2 Comments

Let’s do a Halo Orbit

Cislunar and Lagrangean Points03 November 2015

Let’s do a Halo Orbit

Near the end of my previous post I mentioned Halo Orbit at a Lagrange Point, but presented very little detailed information.

I think the subject is interesting and deserves more space on this blog, so here we go . . .

We have been sending satellites into halo orbits at Lagrange Points since the International Sun-Earth Explorer (ISEE-3) was Launched 12 August 1978 and placed into a Halo Orbit at the Sun-Earth L1 Lagrange Point 20 November 1978 and remained in operation there for a few years.

The ISSE-3 satellite’s needed an unobstructed view of the Sun so the Lagrange point located 1.5 million kilometers away from the Earth is an ideal place for it.

The artist drawing below illustrates ISEE-3 in orbit.

ISEE3 in orbit drawing

Getting a satellite into a Halo Orbit and/or chasing a comet is a rather complicated precess, as illustrated below . . .

ISEE# Launch to Obit

The rocket scientists at NASA have their work cut out for them !

The simplified diagram below illustrates how a more recent satellite, Solar and Heliospheric Observatory (SOHO) was placed into a halo orbit at the L1 Sun-Earth Lagrange Point on 14 February 1996. In the diagram, the L1 point is where the X, Y, and Z axis join together.

SOHO Halo Orbit
An artists drawing of SOHO in orbit . . .

SOHO
Halo orbits tend to be unstable because of the “three body problem” – the problem that Newton (the genius who invented calculus) couldn’t figure out. Because of the unstable orbit “stationkeeping” is required to keep a satellite in a halo orbit. This gives Ground Controllers something to do between emergencies.

Here is a paraphrased definition of the “three body problem” that I found in Wikipedia:
[[ The three-body problem is a class of problems in classical or quantum mechanics that model the motion of three bodies or particles. ]]

Enough said – let us move on . . .

I’ll end this post with a quote from Wikipedia:

” A halo orbit is a periodic, three-dimensional orbit near the L1, L2 or L3 Lagrange points in the three-body problem of orbital mechanics. Although a spacecraft in a halo orbit moves in a circular path around the Lagrange point, it does not technically orbit the actual Lagrange point, because the Lagrange point is just an equilibrium point with no gravitational pull, but travels in a closed, repeating path near the Lagrange point. Halo orbits are the result of a complicated interaction between the gravitational pull of the two planetary bodies and the Coriolis and centrifugal accelerations on a spacecraft. Halo orbits exist in many three-body systems, such as the Sun–Earth system and the Earth–Moon system. ”

– – – END of Halo Orbits – – –

Posted in Miscellaneous Musings | Tagged , , , | Leave a comment

Trojans, Greeks, Hildas, Horseshoes and Tadpoles

Trojans, Greeks, Hildas, Horseshoes and Tadpoles

Everyone on Earth past the age of 2 probably has at least a casual acquaintance with the Moon. A bit beyond 2 years of age we learn that the Moon tags along during the Earth’s yearly orbit around the sun. Some folks become interested and eventually become stargazers, sometimes known as “back yard astronomers”, like me. A select few, unlike me, get well educated and become rich and/or famous

Be that as it may, let’s take a quick look at what I call the “Earth – Moon System”.

As some (most??) readers probably already know, there are many objects in addition to the Moon that share Earth’s orbital path around the Sun. To understand how that works we must look a little deeper into the Sun-Earth system, as illustrated in the graphic, below (borrowed from Wikipedia and NOT to scale). There are some interesting things and happenings there . . .

Cislunar and Lagrangean Points

An asteroid, or other massive body, can orbit the Lagrange Points (small blue dots) labeled L1, L2, L3, and L4. This is a bit odd because there is really nothing solid located at a Lagrange Point – a Lagrange Point is a confluence of gravity force from relatively nearby objects, in this illustration, where the gravity from the Sun and the Earth come together.

Yes, the gravity from the Moon is also involved, but that complicates things (and makes for a messy illustration)  so let’s ignore that, for now.

These Lagrange Points are relatively small Gravity Wells, sometimes called Gravity Dimples, in the fabric of Space-Time, as illustrated, below, which I have borrowed from Wikipedia.

Gravity Dimple small

Gravity wells or dimples, are a way to understand how gravity works without doing the math.

All we need to know in order to understand what causes Lagrange Points is that anything that has mass can create a depression in Space-Time and the “depression” is what causes what we call “gravity” to happen.

Here is an illustration (borrowed from Wikipedia) that (sort of) illustrates this concept . . .

Gravity Well Vectors

If an object is massive enough it creates a very deep Gravity Well that produces a “Black Hole”, but that’s a story for another day.

That’s quite enough cosmology for now – let’s get back to Trojans, and such.
Earth’s only Trojan, named 2010 TK7, is a 300-meter diameter Asteroid.

The name “Trojan” was first used in 1906 for Jupiter’s Trojans, the asteroids that were observed near the Lagrangian points of Jupiter’s orbit (see below). “Trojan” is sometimes used as a generic term for all objects that orbit around Lagrange Points, and sometimes used for specific Lagrange Points L1, L2, L3, and/or L4.

Notice in the illustration below that the objects are referred to Trojans (green), Hildas (red), and Greeks (also green) depending upon which Lagrange point they gather around. In order to clarify which Trojan or Trojans are being referenced, double -Naming, such as “Greek-Trojan” or “Hilda-Trojan” are used.

Jupiter Trojans

Note, also, the Asteroid Belt in white. At the scale of this drawing, Earth’s one Trojan is not visible.

One other note of interest – – it is quite good neighborly of Jupiter with its huge gravity well to capture all those Trojans, Greeks, and Hildas because some of them were probably headed toward Earth and could have done considerable damage when they collided with our home planet.

For a more detailed discussion (including the names) of about 150 of Jupiter’s Trojans, I suggest a visit to Wikipedia – it would require multiple pages to include all the information here on this blog entry.

Getting back to Earth . . .

2010 TK7, A 300-meter-diameter asteroid, discovered and photographed using the Wide-field Infrared Survey Explorer (WISE) is the only confirmed Earth Trojan. Earth’s lonely Trojan orbits the L4 Lagrange point traveling “in front” of Earth in the Earth’s orbit.

2010 TK7 is shown below in the green circle near lower right-hand corner of the infrared photo, just below the brightest star in the photoPhoto of Earth's only known trojan

There are a dozen or so additional objects in the Earth-Moon “family” and they have rather strange “orbits” as they follow or lead along Earth’s orbital path.

A horseshoe orbit is a complex orbital motion of a small orbiting body (such as an  asteroid) relative to a larger orbiting body (such as a planet). The orbital period of the smaller body is very nearly the same as for the larger body, and its path appears to have a horseshoe shape in a rotating reference frame as viewed from the larger object, as in the drawing of the Sun-Earth-Moon system shown below.Horseshoe Orbit 2

The lighter gray lines represent gravity, which determines the path of Horseshoe orbit (green).

The loop is not closed but will drift forward or backward slightly on each orbit, so that the point it circles will appear to move smoothly along the larger body’s orbit over a long period of time. When the object approaches the Earth closely at either end of its trajectory, its apparent direction changes. Over an entire cycle the center traces the outline of a horseshoe, with the larger body between the ‘horns’.

Asteroids in horseshoe orbits with respect to Earth include 54509 YORP, 2002 AA29, and 2010 SO16.
In closing, there are other types of Trojan orbits, one is called the “Tadpole” because it traces an outline resembling a tadpole. The blue triangles around L4 and L5 illustrate the outline of the Tadpole orbits. Another one is called a “Halo” orbit because it is less complicated (more “normal”) than the other types of orbits.

By the way, the James Web Space Telescope (JWST) scheduled to be launched in October 2018 ( if the U.S. Congress continues to fund it) will be placed in orbit around the Sun-Earth L2 Lagrange Point.

– – –  END of Lagrange Points, etc.  – – –

Posted in Miscellaneous Musings | Leave a comment