Sunday, July 13, 2025

The Age of Origin - Nebulae

Here's the second of my three initial posts looking at some of my astrophotograpy from the Celestron Origin smart telescope. Today, its nebulae. Star clusters will be next.

Let's start off with a popular target from the Northern Hemisphere's winter skies: the Horsehead Nebula. 

An astrophoto showing a nebula in the upper right with a bright star next to it. At center is a red nebula with a dark cloud that looks like a horse's head.

That's the Horsehead Nebula, also known as Barnard 33, at center. It's a dark cloud that's in front of a red cloud of hydrogen gas that lies some 1,300 light years from Earth. To the left of it is a blue-white reflection nebula known as NGC 2023. In the upper left is the Flame Nebula (NGC 2024) and immediately to the right of that is the star known as Alnitak. Alnitak is the left-most star of Orion's Belt.  

Almost three degrees to the east of the Horsehead is Messier 78, an amazing complex of both dark and reflection nebulae located at about the same distance from Earth as the Horsehead Nebula.

A telescopic image of stars showing two bright areas that are embedded in blue-white and black clouds.

M78 is at center and NGC 2071 to the left, but clearly they are part of the same region of space. Both have stars embedded within clouds of gas and dust.

The Rosette Nebula in Monoceros is much larger than the Origin's field of view but I shot a series of overlapping images to create this mosaic. 

A cluster of stars surrounded by colorful ring of gas and dust.
This is a region of star formation that has an open star cluster (NGC 2244) at center that's surrounded by a ring of glowing hydrogen gas that's leftover from its formation.

No visit to the winter skies would be complete without a look at Messier 42, the Great Nebula in Orion. 

A fan-shaped cloud of gas and dust.
M42 is almost too bright, but I think that this image captures it nicely. You can see clouds of dark nebulae, blue reflection nebulae and red hydrogen gas. 

Planetary nebulae are created when a Sun-like star that has evolved into a red giant sheds its outer layers into space. 

Messier 27, the Apple Core Nebula is one of the brighter planetary nebulae:

A telescopic image with a blue-green nebula at center that's reddish on its left & right sides.

It's located about 1,200 light years from Earth in the direction of the constellation of Vulpecula, the Fox. 

Unlike any of the previous images in this post, this image was taken using the nebula filter that Celestron sells to go along with the Origin. The remaining images here also make use of the nebula filter, including the Helix Nebula below:

A circle of orange gas with a blue-green center.
The Helix another planetary nebula and is about half as far away as M27, which is why it is larger in the sky. 

Great targets for summer evenings include Messier 16, the famous Eagle Nebula:

A fan-shaped cloud of mostly reddish gas in a field of stars.

At the center of the Eagle nebula lies the famous "Pillars of Creation" that has been photographed by both the Hubble and Webb Space Telescopes. The pillar-shaped dark features at center within this nebula are a part of this nebula which is creating a new cluster of stars.

At the end of their lives massive stars explode as creating supernovae. A supernova is an expanding cloud of star guts. The Veil Nebula is a part of the Cygnus Loop supernova remnant. The western part of the Veil shown here is also sometimes called the Witch's Broom Nebula:

Elongated wisps of blue and red gas near a bright star.
The supernova that created the Veil Nebula exploded between ten and twenty thousand years ago.

A star that has not yet exploded, but someday will, is Wolf-Rayet 136, a massive star that has shed some of its gas creating what is known as the Crescent Nebula (NGC 6888):

An image of a dense field of stars with a red somewhat crescent shaped cloud of gas at center.
That's WR 136 at center. It lies some 5,000 light years from Earth and when it explodes it will be bright enough to be seen in the daytime. Alas, we don't expect this to happen anytime soon.

Finally, here's perhaps my favorite nebula, Messier 8, the Lagoon Nebula in Sagittarius:

Like M42 above, if you are observing in an area free from light pollution the Lagoon Nebula is just visible to the eye. Through a telescope its a grayish cloud associated with an open star cluster. 

There's a famous image of the Lagoon Nebula that was one of the first color images of space. It taken before I was born with the 200-inch Hale Telescope at Palomar Observatory. You can see it on my old Palomar Skies blog from when I worked at the observatory.
 

Thursday, July 3, 2025

The Age of Origin - Galaxies

It's no secret that I am a big fan of smart telescopes, so I was quite interested when Celestron introduced their new Origin smart telescope last year. I was able to get one in November and I thought I would use this post to show off some of the images that I have taken with it. This post will focus just on images of galaxies.

Most of the images here are less than an hour of observing time and have minimal post processing by me, showing off how impressive the Origin is at capturing the cosmos. 

One of my first targets was Messier 31, the Andromeda Galaxy. 

A photo of a spiral galaxy with two companion galaxies
Two of its satellite galaxies are visible. M32 on the right and M110 in the upper left. 

The Origin has a wider field of view than the Unistellar telescopes that I have been using, but its not big enough to catch all of M31. Later this year I'll try a mosaic to try to capture the full view.

Also located within the constellation of Andromeda is the edge-on spiral galaxy NGC 891. At a distance of 32 million light years its 14.5 times farther away than M31, so it looks somewhat lonely in space.

A photo of an edge-on spiral galaxy with a dust lane .
NGC 891 has a nice dust lane that cuts across it and may be somewhat similar to our own Milky Way galaxy.

NGC 253, the Sculptor Galaxy, is located 12 million light years away and is a nice target:

A telescopic image of a spiral galaxy

Located at about the same distance, but in different part of the sky is a great pair of galaxies Messier 82 and Messier 81 in Ursa Major.

A telescopic image of two galaxies
That's M82 on the left. M82 is classified as a "starburst" galaxy due to a period of rapid star formation, which is likely the result gravitational interactions with M81 at right.

Two galaxies at once is nice, but how about three?

 Here are the three galaxies of the Leo Triplet.

A photo of three spiral galaxies

That's NGC 3628 (the Hamburger Galaxy) at left, Messier 66 in the lower right and Messier 65 is above that. At a distance of 42 million light years M65 is the furthest of the three, while NGC 3628 is the closest with a distance of "only" 35 million light years.

Looking further out into space and you can take in many galaxies at once. Here's a portion of the Virgo Cluster of galaxies known as Markarian's Chain.

A photo of a cluster of galaxies
The view is dominated by two giant elliptical galaxies: Messier 84 near the top right and Messier 86 near the center. Respectively they are 66 and 57 million light years away. Numerous other galaxies of the Virgo Cluster can be seen as well.

I have yet to shoot even more distant galaxy clusters, so I'll end with two galaxies that just look good.

 

That's Messier 51, the Whirlpool Galaxy, at right. Its spiral arms spin out to the left to a smaller galaxy, NGC 5195. The two galaxies are interacting and located some 28 and 25 million light years away respectively. M51 was the first galaxy discovered to have a spiral shape is a beautiful target.

My next post will show off some of the nebulae I have photographed using the Celestron Origin. 


 

Thursday, June 26, 2025

Exoplanets!

 I did a lot of citizen science observations during my sabbatical last fall. I was especially interested in trying to use my time to make observations of exoplanets.

My exoplanet observations were all made using the transit method. These planets are impossible to see directly but they can still be detected. As an orbiting exoplanet passes directly in front of (transits) across the face of its star it makes a mini-eclipse and blocks a small percentage of the star’s light. This can be measured even with small telescopes, making this technique the most successful method for studying exoplanets. A typical exoplanet observation lasts from four to five hours, though some are shorter, and others are longer.

Over the course of the semester, I attempted to observe sixteen exoplanet transits. Due a variety of factors (weather, equipment failure, etc.), not all of them were successful. All of my observations were made with a Unistellar eVscope2. A summary of my exoplanet observations is included below along with other findings about these exoplanets.

A note about exoplanet names. Most of them are terrible acronyms of the survey the first discovered the exoplanet, followed by a letter, which indicates the order of discovery within that particular system (starting with the letter b). As an example WASP stands for Wide Angle Search for Planets. WASP-33b refers to the first planet (b) within the 33rd system discovered by that survey. Some exoplanet names are acronyms within acronyms. TOI is TESS Object of Interest. TESS is the Transiting Exoplanet Survey Satellite.

XO-7b               Observed August 23/24, 2024 & October 5-6, 2024

A graph of relative brightness verses time for an observation of an exoplanet transit

A graph of the science results is generated for each exoplanet observation. The graph for one of my two observations of XO-7b is above. Note that the dates are given in Universal Time (essentially, the time in Greenwich, England) which is why these graphs don’t always agree with the local date.

XO-7b is a gas giant planet that orbits a spectral type F star that is larger and hotter than the Sun. It is located 764 light-years from Earth in the constellation of Draco, the Dragon. It is an example of a “hot Jupiter” type planet, as are the majority of exoplanets that can be observed with a small telescope. It is located very close to its parent star, at a distance that is just 4.421% of the distance Earth is from the Sun. It orbits its parent star every 2.9 Earth days! The planet is smaller than in mass (0.709 times Jupiter’s mass or 225 times Earth’s mass), but larger than Jupiter in size. Its larger size is because the tremendous heat that it receives from its star essentially inflates the planet giving it a radius that is almost 1.4 times that of Jupiter’s. The calculated temperature for the planet is 2,678oF. 

TOI-1518b                     Observed August 27/28, 2024

A graph of brightness versus time for an exoplanet transit for TOI-1518b

Note: there were clouds at the end of the observation.

TOI-1518b is a gas giant planet that orbits a rapidly rotating F-type star, which is larger than the Sun (1.95 times the Sun’s radius) and 2,750oF hotter than the Sun’s surface temperature. It is located 737 light-years from Earth in the constellation of Cepheus, the King. The planet has a mass 2.3 times that of Jupiter and a radius that is 1.9 times that of Jupiter. More massive gas planets tend to be smaller as the extra mass causes more compression from gravity. The fact that TOI-1518b is so large indicates that it is inflated due to the temperature caused by how close it is to its star. It orbits its star every 1.9 days in an orbit that is just 3.89% the size of the Earth-Sun distance. The planet is considered to be an ‘ultra-hot’ Jupiter. Its dayside temperature has been measured to be 5,367 oF! It is believed to have ionized iron vapor in its atmosphere.

TOI-1259 Ab                 Observed September 24/25, 2024

A graph of an exoplanet transit for TOI-1259 Ab

The TOI-1259 is a binary star system. The system is located 385 light years from Earth in the direction of the constellation of Draco, the Dragon. TOI-1259 A is a spectral type K star that has a radius 71% of the Sun’s and is about 2,000oF cooler than the Sun. The other star, TOI-1259 B, is a white dwarf. The white dwarf is a distant companion, being 1648 times farther from A than the distance between Earth and the Sun. White dwarfs are essentially dead stars. In this case TOI-1259 B would have begun as a star that was more massive than A (1.59 times the mass of the Sun) and burned through its hydrogen fuel at a faster rate. It now has a mass of 0.56 times the mass of the Sun. Astronomers have determined the age of the white dwarf, and thus the age of the system, which is thought to be 4.8 billion years (Our solar system is 4.6 billion years old.).

The exoplanet is named TOI-1259 Ab. It is a gas giant planet with a mass is 0.44 of Jupiter’s but it is slightly larger than Jupiter in size (1.02x Jupiter’s radius). It orbits star A every 3.5 days at a distance of 4.07% of the Earth-Sun distance.

Observations at Palomar and Keck suggest that the planet receives extreme heating on its dayside which is both causing some of its atmosphere to escape to space and also driving extreme winds that blow from the dayside to the night side of the planet. The equilibrium temperature of the planet is estimated to be 1,190 oF. 

WASP-33b                    Observed September 25/26, 2024
A graph for an exoplanet transit for WASP-33b

WASP-33b is a gas giant exoplanet 398 light years in the direction of the constellation of Andromeda. It orbits a variable star which is larger (1.5 times the Sun’s radius) and nearly 3,000oF hotter than the Sun. It orbits the star every 1.2 Earth days (!) at a distance that is just 2.39% of the distance between the Earth and Sun. Unlike most planets, WASP-33b has a retrograde orbit, meaning that it does not revolve in the same direction that its star rotates. It has a mass that twice that of Jupiter and is about 1.9 Jupiters in radius. The temperature of the exoplanet is 5,790oF. Researchers using the Hubble Space Telescope have detected titanium oxide, a major component of sunscreen, in the atmosphere of this planet. Iron and silicon have also been detected in its atmosphere.

WASP-2b                      Observed September 27, 2024

WASP-2b is a hot Jupiter-type gas giant planet that orbits a K-type star located 500 light years from Earth in the direction of the constellation of Delphinus, the Dolphin. The planet’s host star has a mass that is 85% of the Sun’s, it is 82% of the Sun’s radius. It is 1,154oF cooler than the Sun. The planet has an orbital period of 2.2 Earth days at a distance that is just 3.1% of the distance between the Earth and Sun. Its mass is 93.1% of Jupiter’s and it is slightly larger than Jupiter in size. The planet has a density similar to that of water. The temperature of the exoplanet is 1,855oF. Spectroscopic observations suggest that it has a cloudy atmosphere. 

WASP-93b                    Observed September 28/29, 2024
A graph of an exoplanet transit for WASP-93b

WASP-93b is a hot Jupiter-type gas giant planet that orbits an F-type star located 1,208 light years from Earth in the direction of the constellation of Cassiopeia, the Queen. This star is both larger and hotter than the Sun.

The planet has an orbital period of 2.7 Earth days and orbits at a distance that is just 4.2% of the Earth-Sun distance. It has 1.47 times Jupiter’s mass and is 1.7 times Jupiter’s radius.  The planet’s equilibrium temperature is estimated to be 3,000oF.

HAT-P-32b                    Observed October 4/5, 2024

HAT-P-32b is a gas giant planet that orbits a type F star located 943 lights from Earth in the direction of the constellation of Andromeda, the Princess. The planet has a mass that is just 68% that of Jupiter. It orbits its star at a distance that is just 3.3% of Earth’s distance from the Sun. Its close distance to its star has inflated the size of the planet making it nearly twice Jupiter’s radius. This in turn means that the planet has a low density. All of the “hot Jupiters” observed so far have densities lower than water’s 1 g/cm3, meaning that they are made of light materials (in our Solar System only Saturn, which has a density of 0.69 g/cm3 has density lower than water). HAT-P-32b has a density of just 0.1085 g/cmthis is low enough to almost put it into the category of “super-puff” (yes, that’s a real thing) exoplanets, which have densities less than 0.1 g/cm3.

TIC 362220946.01     Observed October 10/11, 2024

A graph of an observation for a possible exoplanet.
TIC 362220946.01 is a possible exoplanet that was first observed by NASA’s TESS satellite. It was thought that this planet has an orbital period of 8 days and a mass that is 23 times that of Jupiter. I was one of nine observers from the U.S. and Mexico who looked this system in an attempt to confirm its existence and the possible orbital period of the planet. The results were inconclusive but there are suggestions that this could perhaps be a binary star system instead of a planetary system. Further observations may help to solve this puzzle.

WASP-77 Ab                Observed October 24/25, 2024

A graph of an exoplanet transit observation for WASP-77 Ab

WASP-77 Ab is another “hot Jupiter” type gas giant planet. It is located 343 light years from Earth and orbits a Sun-like star in the constellation of Cetus, the Whale. The star is part of a wide binary system, where the other star is a spectral type K star that is smaller and cooler than the Sun.  has a mass 1.67 times that of Jupiter and is 1.23 times Jupiter’s radius. It orbits its star every 1.4 Earth days at a distance of 2.3% that of the Earth-Sun distance. The planet has a calculated temperature of just over 2,600oF.

TOI 6881.01                 Observed October 31, 2024

A graph of an exoplanet transit for TOI 6881.01

The exoplanet known as TOI 6881.01 orbits a star that is 2,559 light years from Earth in the direction of the constellation of Perseus, the Hero. Its star is larger, hotter and more massive than the Sun. The planet orbits its star every 1.9769 days. The planet has a calculated equilibrium temperature of almost 3,100oF. The planet has a mass that is essentially the same a Jupiter’s and a radius 1.44 times that of Jupiter, making it another “hot Jupiter” gas planet that has expanded from the extreme heat from being right next to its star.

TOI-5571.01                 Observed December 4, 2024 & December 18, 2024

A graph of an observation of a possible exoplanet

TOI-5571.01 was initially detected by NASA’s TESS satellite, but its observations were widely spaced in time and so the orbital elements of this exoplanet were highly uncertain. Early observations suggested that the exoplanet could have an orbital period of 731 days (2 years) but was more likely to be something shorter. My observation was part of a campaign by Unistellar to help pin down the exact orbital period of the planet. My observations the night of December 4 (my birthday!) did seem to catch the exoplanet transiting in front of its star (though it was low in the sky), which may indicate that the planet’s orbital period is potentially 66 days, but further observations are needed.