S.M. Pritchard
LightNews LightNews
banner
smpritchard.bsky.social
S.M. Pritchard
@smpritchard.bsky.social
540 followers 460 following 1.2K posts
Physics BSc. | Hard SF Writer/Worldbuilder | Space Artist | Amateur (hopefully one day professional) Astronomer | They/Them | Opinions my own
Posts Replies Media Videos
smpritchard.bsky.social
Confirmation of ID via Tycho Tracker
Screenshot of the software program Tycho Tracker, identifying the fuzzy object as 3I.
November 14, 2025 at 12:29 PM
smpritchard.bsky.social
I finally managed to capture our friendly interstellar visitor, 3I/ATLAS. This is just 4 minutes of movement. 3I is absolutely zipping through the Solar System! You can see the coma surrounding the comet's nucleus, still outgassing icy vapor. Amazing to consider this came from another star.
🔭🧪
November 14, 2025 at 12:21 PM
smpritchard.bsky.social
Decent aurora showing down here in southern PA!
November 12, 2025 at 1:48 AM
smpritchard.bsky.social
Might have missed max intensity I fear
November 12, 2025 at 1:19 AM
smpritchard.bsky.social
Maybe a little something here in southern PA but there's also a town to the north so light pollution is pretty bad that way
November 12, 2025 at 1:14 AM
smpritchard.bsky.social
And now for some more science, also from last night. This is a plot of brightness for the δ Scuti variable star SZ Lyncis. These regular dips and peaks are a result of the star physically expanding and contracting in cycles of rhythmic pulsation, driven by changes in opacity in its chromosphere!
🔭🧪
A plot of magnitude vs time for the star SZ Lyncis. The title reads: SZ Lyncis 2025.11.06. The subtitle reads: Celestron 0.2-m f/5 Newtonian (V filter, 10s exp, fap 16-25-48). The plot legend is a blue dot labeled Source_AMag_T1 ppt) SZ Lyn. The x-axis is labeled "Barycentric Julian Date (TBD) - 2460986 (mid-exposure)". It runs in increments of 0.02 starting from 0.70 up to 0.92. The y-axis is labeled "V Mag". It runs in increments of 0.05 and spans from 9.55 to 9.00. The plot shows a roughly sinusoidal curve with two troughs and two peaks.
November 7, 2025 at 10:53 PM
smpritchard.bsky.social
My first image since getting my mount repaired, the core of the Andromeda Galaxy (M31)! This is only about 3 hours of total integration time (about 1 hour in each color channel). I decided to switch targets after it crossed the meridian...
🔭
A bright yellow-white core of a large spiral galaxy. Dark dust lanes of the galaxy's spiral arms obscure some of the glow. The foreground is sprinkled with hundreds of tiny stars.
November 7, 2025 at 10:40 PM
smpritchard.bsky.social
Aw yeah we're back in business. First clear night since getting my mount back from repairs (and of course the Moon is out and obnoxiously bright)
A black telescope on a tripod sitting in the grass. There are various cables hanging off it. A small white wicker table is sitting behind it, with a laptop on top.
November 7, 2025 at 5:49 AM
smpritchard.bsky.social
There is no greater sin than not including radiators on your spacecraft. Repent and find salvation in the Chruch of the Incandescent Radiator.

A cute little piece I did back in 2022 that I rediscovered.
A poster with a dark blue background peppered with tiny white point-like stars and pink and purple lines framing the sides. In the center is a stylized image of a torchship with glowing radiatior panels. A V-shaped purple plume is coming out of the magnetic nozzle, with a central pink beam. At the top of the image is a stylized depiction of a fusion reaction using red and white half-circles to represent nucleons. Three tricolor beams of yellow, red, and blue emminate from a white starbust shape, representing the energy liberated from fusion. There is text on both the left and right sides running vertically down the image. The left side reads: "CHURCH OF THE", and the right side reads: "INCANDESCENT RADIATOR". There is an artist's digital signature in the bottom right-hand corner.
October 23, 2025 at 8:30 PM
smpritchard.bsky.social
M33, the Triangulum Galaxy. Composite image with just under 4 hours of total integration time. It's the third-largest galaxy in the Local Group, the first being Andromeda and the second being our own Milky Way. It's also the second-closest major galaxy, sitting at ~2.7 million lightyears. 🔭
A photo of a large spiral galaxy. The arms are somewhat indistinct and subtle, but two major ones can be made out. Dark dust lanes snake their away through the arms like veins. Several large pink clumps dot the face of the disk, each one a vast star-forming region hundreds to thousands of lightyears across. The center of the galaxy glows with a soft pale yellow light. The outer regions are a dimmer bluish-purple. Many foreground stars are also present, all of which are much closer than the Triangulum galaxy and sit within the Milky Way, just happening to be between the viewer and the galaxy behind them.
October 7, 2025 at 8:03 PM
smpritchard.bsky.social
September 23, 2025 at 3:18 PM
smpritchard.bsky.social
Hi! I have an 8-inch newtonian on an AVX mount. My main camera is a ZWO ASI533MM and I have a smaller ASI174 Mini for guiding using an off-axis guider. I also have a filter wheel with a few photometric filters installed.
September 12, 2025 at 3:59 PM
smpritchard.bsky.social
And here's an animated timelapse showing the flare!
September 11, 2025 at 4:38 AM
smpritchard.bsky.social
I processed some photometry of the flare star EV Lacertae from the other night and found I had recorded a frightfully strong outburst! Imagine if the Sun suddenly brightened by a factor of 2.5 for a few minutes! But that's nothing compared to the record-holder flare for this star! 🔭🧪
A plot of magnitude vs time for the star EV Lacertae. The x-axis is labeled "Barycentric Julian Date (TBD) - 2460927 (mid-exposure)". It runs in increments of 0.02 starting from 0.56 up to 0.88. The y-axis is labeled "V Mag". It runs in increments of 0.1 and spans from 10.30 to 9.30. There is a large spike at the beginning of the plot, indicating a massive flare eruption on the surface of the star. There is a small gap in data in the middle of the lightcurve. A vertical light blue dashed line runs up the middle of the gap, labeled "Meridian Flip".
September 11, 2025 at 4:07 AM
smpritchard.bsky.social
A nice, clean lightcurve of last night's transit of exoplanet TrES-1b, a hot Jupiter 523 LY away in the constellation of Lyra. It has a radius of 1.08 Jupiters and a temp of 1060 K. Despite some troublesome guiding errors with my mount, I'm quite pleased with how clean the data are. 🔭🧪 #exoplanets
A lightcurve graph of the star TrES-1 showing the characteristic dip as its hot Jupiter exoplanet passes in front of it and gradually dims its light. The y-axis is relative flux. The x-axis is time, measured in the barycentric julian date (BJD). The graph is drawn in blue, and a best-fit curve is drawn between the points, tracing a U-shaped dip. There are two red vertical dashed lines that roughly mark the start and end of the U-shaped dip. The first is labeled "predicted ingress" and the second is labeled "predicted egress". A black-and-white image of a starfield. In the upper left-hand corner is a blue box with a set of yellow and green arrows. The yellow arrows are pointing up and left but slightly rotated clockwise, and are labeled "N" and "E" respectively. The green arrows are pointing right and down and labeled "X" and "Y" respectively. At the top is a yellow scale bar labeled 7.63'. On the left-hand side of the image is another yellow scale bar oriented vertically labeled 7.65'. There is a series of green concetric circles around a star roughly in the middle of the image, labeled T1=1.114E6. This is the target star. Surrounding the target star are 7 other stars with a series of concentric red circles. Starting from the top and moving down, they are labeled C8=1.18E6, C3=1.109E6, C2=1.12E6, C4=1.029E6, and C7=9.646E5. The two near the lower left corner of the image are too close together to distinguish.
September 10, 2025 at 11:43 PM
smpritchard.bsky.social
Continuing my monitoring of the flare star EV Lacertae. I had to contend with a few unforeseen clouds which resulted in some breaks in the data, but I also caught a massive flare right at the end of the session! 🔭🧪
A plot of magnitude vs time for the star EV Lacertae. The x-axis is labeled "Barycentric Julian Date (TBD) - 2460922 (mid-exposure)". It runs in increments of 0.05 starting from 0.55 up to 0.85. The y-axis is labeled "V Mag". It also runs in increments of 0.05 and spans 10.30 to 10.00. There are several gaps in the datapoints where cloudcover made photometric measurements impossible. There is a large spike at the end of the plot, indicating a massive flare eruption on the surface of the star.
September 5, 2025 at 2:33 AM
smpritchard.bsky.social
Probably somewhere about here
A chart with 2 axes dividing the space into 4 quadrants. The top is labeled "Gerard O'Neil Cylinder Extravaganza", the right is labeled "Infinite Dubai Forever", the bottom is labeled "Earthlikes Everywhere", and the left is labeled "Better Things Are Possible". There is a purple dot in the upper left quadrant about a quarter of the way up the "Gerard O'Neil Cylinder Extravaganza" axis and most of the way to the left of the "Better Things Are Possible" axis.
September 4, 2025 at 9:06 PM
smpritchard.bsky.social
Last night's transit of exoplanet WASP-2 b, one of many hot Jupiter planets found by the Wide Angle Search for Planets! WASP-2 b was discovered in 2008 and orbits in just 2.15 days. The star WASP-2 is actually a binary, consisting of a K-type primary and a distant M-dwarf.
🔭🧪 #exoplanets
A lightcurve graph of the star WASP-2 showing the characteristic dip as its hot Jupiter exoplanet passes in front of it and gradually dims its light. The y-axis is relative flux. The x-axis is time, measured in the barycentric julian date (BJD). The graph is drawn in blue, and a best-fit curve is drawn between the points, tracing a U-shaped dip. There are two red vertical dashed lines that roughly mark the start and end of the U-shaped dip. The first is labeled "predicted ingress" and the second is labeled "predicted egress". There is a light blue vertical dashed line to the left of the predicted ingress line labeled "meridian flip". A field of hundreds of stars against the dark background of space. A handful have small diffraction spikes. A large red arrow is pointing down towards a white-ish star in the center of the photo.
September 3, 2025 at 11:59 PM
smpritchard.bsky.social
A large H II emission region around the bright star Gamma Cassiopeiae (out of frame). The bluer reflection nebula is IC 59, and the pink emission nebula is IC 63, sometimes rather whimsically called the Ghost of Cassiopeia. Total integration time of 8 hours (2 hours 40 minutes per color channel).
A star field full of thousands of stars. They are a mix of blue-white, white, and yellow-orange. There are 3 clouds of nebulosity in the image; two on the left and one on the right. The top left cloud is small and faint, with a dim purple-blue interior and pink rim. The bottom left cloud is much larger and brighter, with a clearly-defined, brightly glowing pink rim. It is vaguely funnel-shaped, with the cone of the funnel pointing towards the bottom of the image. The cloud on the right is large and dim, and is mostly a dull blue-purple color. Just off screen at the bottom right is a large vertical diffraction spike from the star Gamma Cassiopeiea, which is illuminating the entire nebular complex.
September 1, 2025 at 11:49 PM
smpritchard.bsky.social
Last night I began collecting photometry on the nearby flare star EV Lacertae. It's a young M-dwarf just 300 million years old known for frequent and intense flares, some of which are tens of thousands of times brighter than what the Sun can produce! I recorded two eruptions over about 5 hours. 🔭
A starfield containing many hundreds of stars, most of which are faint orange-yellow dots with a few whiter star in between. In the upper right-hand corner is a bright blue-white star with diffraction spikes. Near the center of the image is a red arrow pointing down to a yellow-orange star. A plot of magnitude vs time for the star EV Lacertae. The x-axis is labeled "Barycentric Julian Date (TBD) - 2460910 (mid-exposure)". It runs in increments of 0.05 starting from 0.60 up to 0.80. The y-axis is labeled "V Mag". It also runs in increments of 0.05 and spans 10.30 to 10.00. There are two prominent peaks. The first peak is over twice as high as the second peak. Each peak is a massive flare eruption on the surface of the star.
August 24, 2025 at 2:57 AM
smpritchard.bsky.social
The Bubble Nebula, in the constellation of Cassiopeia. The bubble itself is a shell of material cast off by the intense winds of the bright star SAO 20575 inside. The radiation also illuminates a vast cloud which surrounds the region, causing it to glow the characteristic red of ionized hydrogen. 🔭
A red cloud surrounded by many hundreds of stars. There are several very bright blue, white, and yellow stars with prominent diffraction spikes. Near the center of the red cloud is a somewhat fainter pinkish ring, somewhat like a soap bubble.
August 18, 2025 at 11:43 PM
smpritchard.bsky.social
🔭 The Elephant's Trunk, part of the larger emission nebula IC 1396. The red is ionized hydrogen, glowing under the intense UV light of the nearby triple star HD 206267, out of frame but "above" the tip of the trunk.
A dense starfield with many hundreds of orange, blue, and white stars. Some of the stars are obscured by thick dark clouds. The clouds form a long chain pointing upwards in the center of the image, giving the impression of the trunk of an elephant. The dark clouds are rimmed by the red glow of ionized hydrogen. At the tip of the trunk is a small cavity illuminated by a yellow-orange star.
August 8, 2025 at 12:47 AM
smpritchard.bsky.social
August 7, 2025 at 10:00 PM
smpritchard.bsky.social
I've seen them in my light frames a few times. I've not looked over any of my bias frames to see if I've caught any in though (I don't take darks, my camera doesn't need them since it doesn't have amp glow).
July 30, 2025 at 5:02 AM
smpritchard.bsky.social
Oh same! What's your target tonight?
July 25, 2025 at 2:35 AM