NASA Highlights: Astronomical Photos of the Week (11/27 – 12/03/2021)

How about starting the weekend by viewing the latest astronomical photos highlighted NASA? In this collection you will find images of galaxies of different types, one with a spiral structure, the other with an irregular structure, and it is certain that they are all amazing. In addition, you also see the entry about comet Leonard accompanied by galaxies of curious shapes.

You can also find videos of Uranus accompanied by some of its moons. And speaking of natural satellites, you can also admire the beautiful image of the moon taken during a partial lunar eclipse.

Come on?

Saturday (27) – Weather Vane Galaxy

Galaxy M101, also known as the Weather Vane Galaxy, appears here in one of the largest images of a spiral galaxy ever taken by the Hubble Space Telescope. The object just recorded here is 170,000 light-years across – bear in mind that this is almost double the diameter of the Milky Way.

Astronomers believe that M101 contains at least a trillion stars, as well as numerous nebulae scattered around its arms. These nebulae contain giant molecular clouds of hydrogen, which are regions of intense star formation. Areas of blue indicate young clusters formed by hot, bluish, and newborn stars.

The Weather Vane Galaxy is located about 25 million light-years from Earth in the direction of the constellation Ursa Major and can usually be observed with small telescopes. This image is the result of a combination of 51 exposures from several studies conducted over nearly a decade and combines information from infrared and visible light.

Domingo (28) – Comet Churyumov-Gerasimenko

Is it part of some distant planet or moon? In fact, it is one of several details of Comet Churyumov-Gerasimenko (CG) recorded by the European Space Agency (ESA) Rosetta mission. The spacecraft arrived in 2014 and spent some time in orbit to collect data until it made a controlled landing on its surface in 2016.

The rock that appears here is about 1 km high, and if you dared to climb it, you could even climb it with ease, since the comet has low surface gravity. At the foot of the cliff there is a relatively soft relief with rocks up to 20 m in length.

Mission data show that the ice from the CG contains a different amount of deuterium than the water in the Earth’s oceans. Comet Churyumov-Gerasimenko consists of 26 different regions, each of which is named after some Egyptian deity. The areas of the larger wolf comet were named after the gods, and the areas of the smaller ones were named after the goddesses.

Monday (29) – Cosmic Mystery

The image above shows a mysterious and intriguing object, as it is unclear what formed this spiral structure in the upper left corner.

One possibility is that it is a rare preplanetary nebula forming around the L.L. Pegasus; in these systems, two stars revolve around a common center of mass. Typically, the brightest star is classified as the primary star in these systems, and the darkest as the secondary.

The spiral may have been formed by an ongoing process in the LL Pegasi system in which one of the stars loses material to its neighbor. Moreover, it is possible that the binary system is turning into a planetary nebula; This is the end of life for red giant stars as they expand layers of ionized gas.

In the image shown here, the rate of expansion of the gas seems to indicate that a new layer will appear in about 800 years, a period that corresponds to the period it takes for two stars to orbit each other. Another mystery relates to the glow of the spiral, possibly caused by light reflected from nearby stars.

Tuesday (30) – Uranus and several moons

This video shows the glow of Uranus and its moons recorded by the Bayfordbury Observatory in Hertfordshire, UK.

Despite only lasting a few seconds, the sequence shows four hours of observation over this distant system, formed by a planet four times the size of Earth.

You might not want to travel to Uranus, as temperatures, pressures, and materials in this distant world are too extreme and volatile for life as we know it. To get an idea, imagine life expectancy there is about 84 Earth years, and winters are 21 years.

Astronomers today have identified 27 moons orbiting the planet – and unlike most of our solar system’s neighbors, they are named after the works of the poets William Shakespeare and Alexander Pope. In this video, we saw the moons Titania, Oberon, Umbriel and Ariel.

Wednesday (1) – Colors of the Moon

We are used to seeing the moon in gray tones, but there are other colors in the photo above. The image was taken during a recent partial lunar eclipse and has some interesting effects: the gray tones of the lower part of the lunar disk are a typical color of our natural satellite, originating from compounds present on the lunar surface such as oxygen, silicon, magnesium, iron and others.

Darker areas are formed by ancient volcanic eruptions and reflect less light, so they appear darker. The reddish part is the result of a process similar to that which causes the red colors of sunset and sunrise. As sunlight passes through the atmosphere during an eclipse, some of the colors in the spectrum are “filtered”.

Since the wavelengths of red light are least affected, they reach the moon and make it reddish. Finally, we are left with this little blue streak in the center of the lunar disk, which is simply the result of sunlight passing through the upper part of the Earth’s atmosphere.

Thursday (22) – Barnard’s Galaxy

Here we have the galaxy NGC 6822. Also known as “Barnard’s Galaxy”, it is only 1.5 million light years away in the direction of the constellation Sagittarius and is approximately 7000 light years across.

It is an irregular dwarf galaxy that is typically low in metallicity and relatively high in gas. This makes it a good tool to help astronomers better understand the evolution of galaxies.

Some of the irregular galaxies may have been spiral-shaped, but they were distorted by the gravity of a nearby object, which ultimately affected their structure. In the image, we see several blue and young stars in Barnard’s Galaxy, also accompanied by a pink glow.

This color, present in only a few regions, is associated with the release of hydrogen from regions where star formation occurs. NGC 6822 is also part of the Local Group of more than 50 galaxies, with the largest members being Andromeda, the Triangle, and the Milky Way itself.

Friday (03) – Leonard’s Comet and the Galaxy

Have you ever thought about seeing a comet between two different galaxies? This is exactly what is depicted in this photograph of Comet Leonard (C / 2021 A1), which appears to traverse the space between two galaxies.

It is getting closer and closer to the Earth and the Sun, but 35 thousand years ago, Leonard was 525 billion kilometers from our star; December 12 Leonard will be as close to Earth as possible. After Christmas, the comet should leave our field of view, reaching the point closest to the Sun on January 3. After it orbits the star, it will be launched outside the solar system and will no longer be visible.

In addition to the comet, there are several interesting galaxies in the image: at the top is NGC 4631, known as the “Whale Galaxy”. It is a spiral galaxy as viewed from the Earth; so the slight distortion of its disk seems like a whale.

The other is NGC 4656, called the “Stick Galaxy,” whose curious shape may have been the result of interactions with other galaxies. Of course, the apparent proximity of a comet to galaxies is just an impression, since they have over 25 million light rays. years away.

A source: Astronomical picture of the day