NASA's OSIRIS-REx spacecraft is set to sample the diamond-shaped asteroid Bennu. Credit: NASA/Goddard/University of Arizona
NASA is about to grab its first-ever taste of an asteroid. On 20 October, some 334 million kilometres from Earth, the agency's OSIRIS-REx spacecraft will approach a dark-coloured, diamond-shaped asteroid named Bennu, with the aim of touching its surface for a few seconds — long enough to hoover up a collection of dust and pebbles. If successful, the spacecraft will then fly this carbon-rich rubble back to Earth, where scientists can probe it for clues to the history of the Solar System.
In case you are keeping track:
Special Topic: 1I/'Oumuamua - RocketSTEM
W hile the details are always in a state of revision, for quite some time now the general consensus among astronomers as to how the solar system and its planets formed involves the accumulation of smaller objects, "planetesimals." The comets and asteroids we see today, and that have been the primary focus of "Ice and Stone 2020," are the "leftovers" from this process.
We now have good reason to believe that many, if not most or even almost all, other stars have planetary systems of their own. At the same time, it appears that not only is our solar system not a typical planetary system, there really is no such thing as a "typical" planetary system.
Thinking of installing a home solar system with backup batteries?
This was my experience with the latest power outage this week. I have two Tesla Powerwalls. This is a battery backup system. The Powerwall units switch on so fast you don't notice a power drop.
You don't have to reset your clocks. It's nice knowing that even if I'm away, my refrigerator and security lights will be working.
I have a Tesla smartphone app that allows me to monitor my system and control how the system operates. The Powerwalls can be purchased without solar panels.
Easy Crafts from NASA: Make Your Own Exoplanets – Exoplanet Exploration: Planets Beyond our Solar
We’ve discovered thousands of exoplanets – worlds beyond our solar system – so far. Most of these faraway planets are unlike any of the worlds in our own solar system. They are so far from Earth that they’re really hard to see! Even the best pictures we have of them show little more than bright dots of light. We have to use our science to tell us more about what they might look like up close.
We know what colors planets might be, for instance, based on certain chemicals we observe in their atmospheres. You might say there’s an art to our science! Now NASA has an easy arts and crafts project where you can make your own exoplanets at home.
Quite a lot has been going on:
Space probe makes 1st Venus fly-by on way to Mercury
BERLIN (AP) — A spacecraft bound for Mercury swung by Venus on Thursday, using Earth's neighbor to adjust its course on the way to the solar system's smallest and innermost planet.
Launched almost two years ago , the European-Japanese probe BepiColombo took a black-and-white snapshot of Venus from a distance of 17,000 kilometers (10,560 miles), with some of its own instruments in the frame.
The fly-by is the second of nine so-called planetary gravity assists that the spacecraft needs for its seven-year trip to Mercury. The first, around Earth , took place in April.
Solar industry-Xcel flap won't dim long-term growth of Minnesota industry - StarTribune.com
Superior Third Party Logistics, a warehouse and logistics outfit near the fairgrounds in St. Paul, makes a tidy chunk of change selling parking space during the Minnesota State Fair.
* * *
However, crews from Blue Horizon Energy, an 11-year-old solar-engineering firm, were busy in Superior’s parking lot during fair time.
They installed 3 acres of solar arrays and a new roof atop the Superior building. That should save Superior about $90,000 a year in energy costs that will become profit after the $2.4 million project is paid for in about 10 years. Heck, that’s approaching what Superior grosses annually on fair parking.
Evolution, Composition, and Structure of Comets
Comets are very important for understanding the formation of the solar system, and so there has been a concerted effort to learn about their composition, evolution, and structure.
When a comet is seen in the sky, what is typically seen is the extended sublimating atmosphere, also known as the coma, surrounding the comet. A comet's coma can be extremely large, extending for about 100,000 kilometers across—5 to 10 times the diameter of Earth. But the real heart of the comet is the small, solid portion on the inside of the coma, known as the nucleus. This is the only part of the comet that exists when it's in the outer solar system and not outgassing.
Comets: What Are They?
Comets come from the outer solar system. Primarily, they are combinations of ice and dust. These combinations have sometimes been described as ranging from "dirty snowballs" to "icy dirtballs". Comets are kind of like leftovers of planet formation in the outer solar system. Out there, temperatures were low enough for icy materials like water, ammonia, and methane to freeze and create the icy building blocks that formed the outer planets.
Typically, comets have elliptical orbits around the Sun. This means that their distance from the Sun vary much more than Pluto during their orbits. For example, the famous Halley's Comet goes closer to the Sun than Venus, but also farther from the Sun than Neptune, completing a full orbit about every 76 years. Comets can only be seen clearly when their orbits bring them to the inner solar system.
No comments:
Post a Comment