Author: Doris W.

The next generation of planetary exploration kicks off in 2027 when NASA launches the Dragonfly Mission to Titan. Saturn’s moon Titan is the second-largest moon in the solar system.  Clouds, rain (methane), a nitrogen-based atmosphere, and weather patterns similar to Earth have scientists buzzing with excitement. 

Huygen’s Mission-2004

The Huygen probe landed on Titan in 2005 and broadcast data for 72 minutes.  Huygen captured atmospheric data as it descended through the haze and clouds.  Following the touchdown, Huygen captured and transmitted 100 pictures before the batteries ran out of power.  

The pictures and atmospheric data justified a return trip to Titan.  

The Four Phases of the Dragonfly Mission

1. Launch: Leaving Florida in 2027. The launch vehicle hasn’t been announced yet.
2. Cruise:
   • Starts when Dragonfly separates from the launch vehicle.  
   • Ends prior to Dragonfly entering Titan’s atmosphere
3. Entry, descent, landing (EDL).
   • Starts when Dragonfly is 789 miles (1,270 km) above Titan
   • Ends when Dragonfly touches down in a dune near the equator
4. Titan operation/science mission

Dragonfly Structure

The spacecraft has two components.

• Cruise stage-Located at the “top” of the spacecraft.  The cruise stage component separates from the Entry Vehicle at a specified height during atmospheric entry.  The cruise stage components will burn up, similar to how a rocket stage burns up upon reentry through Earth’s atmosphere.
  • The Cruise stage has three components.
    1. Earth Communications
    2. Propulsion
    3. Thermal control
• Entry Vehicle-three components
  • Backshell-Top component
    1. Parachute 
    2. Low gain antenna
    3. Separation systems
  • Rotorcraft lander-Middle component, protected by the Backshell above it and the heatshield below it.  
  • Heatshield-Protects the Rotorcraft lander during atmospheric entry.

Dragonfly in the Air

The Dragonfly weighs approximately 926 pounds (420 kg).  Instead of resting on wheels like previous NASA rovers, Dragonfly will rest on skids, just like a helicopter.  Lift is created via eight 53-inch (1.34 m) counter-rotating rotors.  

Landing

When the EDL is 0.75 miles (1.2 km) above Titan’s surface, the rotorcraft unit will detach from the Backshell and land itself.  Titan’s atmosphere is four times heavier than Earth’s.  Titan’s gravity is one-seventh of Earth’s gravity.  Combined, they create a perfect environment for low-power drone flights.

Surface Mobility 

The “relocatable lander” will fly to different locations during its 37-month ground mission.  The Dragonfly can fly for 30 minutes before recharging is required for the rotor motors.  The Dragonfly travels at a maximal speed of 22mph (33 kph).  Mar rover speeds max out a .1 mph (4,828 meters per hour).  

Data Analysis

Dragonfly has a plethora of hardware to analyze its surroundings.

• Mass Spectrometer: Elemental analysis
• Drills for Regolith samples from the surface and near the surface for analysis
• Gamma-Ray Neutron Spectrometer-Analysis of surface composition near the skids.
• Seismometer-Detect and measure ground movement
• Two LiDAR navigation sensors-realtime navigation sensors
• Ten Cameras to capture images! Close-up, panoramics, mosaic. 
• Optical navigation based on Cassini’s maps created from 127 flybys

Wrap Up

The Dragonfly will explore the chemistry of geographically different environments on the surface of Titan.  The elements, compounds, atmosphere, ocean, and seismic analysis are a window into Earth 3.5 billion years ago.  

Our fingers are crossed that Dragonfly will provide answers concerning whether Titan was once home to life.

The Alpha Centauri System

The Alpha Centauri system is a very typical star system. It is the closest system to the Earth and gets a lot of attention from us since it is relatively easy to observe. Like most star systems, its birthing process produced more than one star; it has three.

Alpha Centauri A and B are Sun-like yellow dwarf stars and form a binary star system. They rotate around a common point and are approximately as close to each other as Saturn and the Sun. The third star, Alpha Centauri C (also called Proxima Centauri) is a Class M red dwarf. It is not clear if Proxima Centauri is rotating around the two Alpha Centauri stars or just happens to be near them.

Is There Life in the Alpha Centauri System?

The most exciting about Proxima Centauri is that it has confirmed planets, one of which is an Earth-like planet within what is called the “habitable zone”, namely it may be the right temperature to support life as we know it. Unfortunately, Proxima Centauri is prone to emitting massive flares of energy at random intervals, which may render the planet unlivable.

What would it be like to live in a three-star solar system?

Alpha Centauri A and B may also have planets (the astronomers are not yet sure about this). If you lived on a planet orbiting Alpha Centauri A, it would appear similar to the Sun viewed from Earth, rising and setting on a regular daily schedule.

Alpha Centauri B would periodically appear in the sky, like the Moon, but much brighter. The two stars have an eccentric orbit that takes around 80 years to complete. At their closest approach, the secondary lighting from Alpha Centauri B on your planet would be as bright as typical indoor lighting. At their furthest approach, the light would be more like a dim porch light. Proxima Centauri, being a dim red dwarf, would just look like any other star in the sky.

Can we visit Alpha Centauri?

NASA is planning to send an unmanned spacecraft to the Alpha Centauri system in 2069, but it would probably take around 44 years before it arrived and another 4 years for its information to start arriving back at Earth, namely in the year 2117.

The Breakthrough Starshot program could, in theory, travel to the Alpha Centauri system in around 20 years. The Starshot program, which was co-founded by Stephen Hawking in 2016, is trying to create light sail spacecraft that can move at around 20% of the speed of light.

The International Space Station (ISS) is so large that it’s visible from Earth without a telescope!  The International Space Station is approximately 250 miles above the surface of the Earth in Low Earth Orbit. Traveling at approximately 17,500 miles per hour, the ISS circles the globe once every ninety minutes. 

Why is the ISS moving across the sky? 

The ISS resides in Low Earth Orbit (LEO). Objects in LEO circle the globe. Objects in Geostationary Orbit (GEO) do not circle the globe and remain stationary above one location.

• Satellites in Low Earth Orbit travel at approximately  4.85 miles per second (7.8 km per second) with an altitude of approximately 160 km to 1000 km above the earth. LEO satellites circle the globe sixteen times each day. The ISS is in LEO.
• Satellites in Geostationary orbit travel approximately 2.26 miles per second (3.8 km per second) with an altitude of approximately 36,000 km above the earth. GEO satellites match the Earth’s rotation speed, appearing “stationary” above the Earth. 

Where do I look? 

The ISS is in a constant state of motion. Atmospheric drag and Earth’s gravity create orbital altitude degradation on the ISS. Changes in the ISS’s altitude modify its trajectory. In theory, the exact orbit path will repeat every three days. 

A good way to determine when the ISS will be traveling near you is to use NASA Spot the Station website. Entry your city, and the website generates a list of upcoming passes near your location. Don’t worry if your exact city isn’t listed. Pick a city that’s close to you. 

Date	Visible	Max Height*	Appears	Disappears
Today, 5:30 AM	5 min	23°	10° above S	10° above ENE
Today, 4:44 PM	2 min	11°	10° above SE	10° above ESE
Tomorrow, 6:18 AM	6 min	29°	10° above WSW	10° above NNE

Here’s an example of a flyby chart from the NASA Spot the Station website based on your current location. 

Which direction should I look?

Take a few moments to orient yourself outdoors. Which direction is N, S, E, W?  

Old School: 

1. Use a compass and orient yourself in the proper direction
2. Use your hands to determine approximate viewing height
   1. Make a fist, knuckles rolled forward, and raise it to eye height
   2. The approximate distance from your thumb to your pinky finger is 10°
   3. Make the “hang loose” or “aloha” symbol with your hand. It’s 25° from your pinky to your thumb.
   4. Pay close attention to the ISS Max Height above the horizon. Landscapes or buildings can easily (easily) cover up to 15-20° of the horizon. 

New School: 

1. Use your favorite cell phone app to orient yourself (N,S,E,W) 
2. Use the app to find the ISS
3. (-) cell phone brightness

There it is!

Now that you’re oriented and know where to look, it’s time to locate the ISS!  Be patient and relax.  Soon enough, you’ll see satellites, even if they’re not the ISS.

When viewing conditions are “correct,” it’s possible to see a string of satellites traversing the nighttime sky lined up in a row.   This unusual sight is known as a Satellite Train.

The number of Low Earth Orbit (LEO) satellites launched is growing each year. The increased number of satellites in orbit has a direct impact on how we view our nighttime skies. Starlink has approximately 3,800 satellites circling the Earth.

Where are the satellites now?

Heavens-Above and Constellation Starlink have fantastic interactive 3D models. The sheer volume of Starlink Satellites is stunning. Select Live Map and locate the satellite train that’s closest to you on Findstarlink, 

Geostationary and Low Earth Orbiting Satellites

• Geostationary (GEO) Satellites are 36,000 km above the Earth.
  • Slow upload/download times.  (High latency.)
• LEO satellites are approximately 160 km to 1000 km above the Earth.
  • Fast upload/download times. (Low latency.)

What’s a Starlink Satellite?

A Starlink Satellite transmits internet signals from a satellite to a ground transceiver. The ground transceiver sends a signal to a router. The end user connects to the internet through the router. 

LEO satellites are constantly “on the move” as they circle the Earth.  This includes crossing over the oceans that cover 71% of the globe.

The best way to ensure global coverage is to place additional satellites into orbit. Each Starlink launch adds approximately 50-60 Starlink Satellites. Starlink is planning on weekly launches.

Who needs it?

Starlink plans to provide high-speed internet access to communities with poor internet service.  Poor service may be due to geographic location or lack of infrastructure.

How Many?

Starlink is the first company to place satellites, in bulk (3,271), into LEO. Starlink currently has FCC approval for 12,000 satellites. Starlink’s projected build-out is closer to 42,000 satellites. A baseline expectation is 100,000 satellites in LEO, (all companies/nations combined) by 2030.

What’s a Starlink Satellite train?

Starlink satellites begin orbit at the approximate height of 350 km and move to an altitude of 550 km. They travel “in a row” as they orbit the Earth. The satellites are visible to the naked eye when they’re at a lower elevation.

A Starlink Satellite train is a row of Satellites traveling across the sky “in a row” or a “string of pearls.”

Astronomers express concern

Astronomers worry that the satellite trains will impact scientific research.  Papers are being published highlighting the satellite train’s negative impact on astronomy.

Astronomers are reflecting on the Kessler syndrome as a real possibility: A satellite breaks or shatters into smaller pieces. A second satellite files through the debris field. The second satellite breaks or shatters into smaller pieces.  Snowball effect.

Moving forward

Faster internet connections may be the beginning of an economic equalizer for less developed regions. Increasing the number of satellites in low earth orbit may cause considerable scientific angst. What’s the right answer?  

The science of astronomy has defined a galaxy as a system of stars, planets, dust, and other materials that revolve around a common center of mass. A galaxy can be very large and include billions of stars.

Many galaxies have names. The names are often based on the constellation or the location of the star. Some galaxies have more interesting names than others. Most of these are named by astronomers who discovered them.

Spiral Galaxies

Spiral galaxies are the brightest galaxies that are far away. They are made up of stars and planets that are rotating in the opposite direction to shape the galaxy. There are lots of colors in the material in these galaxies. Another type of galaxy is an elliptical galaxy. These galaxies are shaped like grains of rice.

Galaxies are grouped together based on their gravitational attraction. Many galaxies are also grouped into clusters. One of these groups is the Local Group of 54 galaxies. This group includes our own Milky Way galaxy. It consists of hundreds of billions of stars.

Types of Galaxies

Most modern catalogs of galaxies contain thousands of objects. The New General Catalog of Principal Galaxies, for example, has over 73,000 objects in it. When a new catalog is published, most of the objects have catalog designations. For instance, the Whirlpool Galaxy is a Messier object. Another example is the Pinwheel Galaxy, which is located in the Coma Benerices constellation.

Galaxies can be classified into three basic types. These are barred spiral, barred elliptical, and elliptical. While most are categorized by their size, some are still grouped by their shape. In general, a galaxy is a collection of planets and stars, but can also be a system of nebulae and dust.

The names of galaxies can vary, depending on how the catalog is compiled. Some galaxies are not included because they do not show up as separate objects in the sky. Others are only part of larger galaxy clusters. An example is the Sagittarius Dwarf Spheroidal Galaxy, which is not listed because it is not seen as a separate galaxy.

There are also a number of unusually shaped galaxies. These include galaxies in the process of colliding, and galaxies with active nuclei. These objects are thought to be in a transitory phase of galactic development.

Where Do Galaxies Get Their Names?

Several ancient cultures named ten thousand stars. However, there are only a few thousand that are bright enough for human observation with the naked eye. Using the names of stars and constellations is a great way to learn about outer space and the universe. You can also visit a planetarium to see displays of deep-space features.

Although it can be challenging to identify certain galaxies, the International Astronomical Union has produced several official catalogs. The New General Catalog of Nebulae and Star Clusters is the most widely used catalog. Other popular catalogs are the Atlas of Peculiar Galaxies, the Extragalactic Catalog, and the Markarian Catalog.

We know that Uranus is the coldest planet in the Solar System, existing at a frigid minus 371 degrees Fahrenheit. Have you ever wondered what the coldest place in the universe is?

It’s well-known that there is a lower temperature limit: absolute zero. At absolute zero (minus 459 degrees Fahrenheit), all of the atomic and subatomic particles stop moving. Temperature measures the kinetic energy of matter. Namely, temperature describes how fast the atomic and subatomic particles in matter are moving. The faster they move, the higher the temperature. When they completely stop moving, they have zero kinetic energy and have reached absolute zero.

If there is no matter, there is no temperature. Thus, a complete vacuum has no temperature. It is neither cold nor hot. Deep space is not a complete vacuum; it has a tiny amount of matter in it that was created and heated by the Big Bang. Space has a temperature of minus 455 degrees Fahrenheit, which is clearly above absolute zero.

Boomerang Nebula: The Coldest Place in the Universe

The coldest place in the universe that anyone has observed so far is the Boomerang Nebula, which is about 5000 light years away from the Earth. Part of the Boomerang Nebula is estimated to be a frigid minus 457 degrees Fahrenheit, actually cooler than deep space and barely above absolute zero. The Boomerang Nebula is believed to be a dying star system. The star is spraying solar winds carrying mass and starlight out into space, where it rapidly expands and the particles push against the particles present in deep space, transferring some of their kinetic energy and causing the area around the dying star to cool below the background temperature of deep space.

Thus, while Uranus may be the coldest planet in the Solar System, it is not the coldest place in the universe and it’s a lot warmer than deep space and significantly warmer than the Boomerang Nebula.