101 SKY OBJECTS
WWW.ASTRONOMY.COM 4971 Flaming Star Nebula
John Martin Schaeberle discovered IC 405 near the end of the
19th century. The object was independently spotted shortly after by
astrophotographers Max Wolf and Eugen von Gothard. It’s located in
Auriga, a constellation better known for its wealth of open clusters, but
whose nebulae are often overlooked.
Also known as the Flaming Star Nebula, this object is a combination
of emission and reflection nebulae illuminated by the unusual variable
star AE Aurigae. The nebula is a large 37' by 19' across, and its brightest
portion sits east of the star. IC 405 lies 1,500 light-years away.
Many objects with low surface brightness that were discovered via
early astrophotography are visible with today’s amateur telescopes,
which are often better than those that deep-sky observers in the late
19th and early 20th centuries were using. The Index Catalogue (from
which the IC number is derived) description of the Flaming Star Nebula
reads, “star of 6.7 magnitude with pretty bright, very large nebula.” With
a description like that, you’d think it would be simple to spot. But like
many expansive nebulae, it isn’t as easy as it sounds. Under dark, dry
skies, IC 405 can be seen with telescopes as small as 2.4 inches. But in
less ideal skies, it may be impossible to see, even with larger apertures.
Winter nights tend to have lower humidity, so if you enjoy bundling up
and observing under frigid temperatures and dark skies, you have a
good chance of picking up this nebula.
If you’ve got weird stars on your bucket list, AE Aurigae is another rea-
son to seek out IC 405. This extremely hot O9.5 star varies a modest 0.7
magnitude (from roughly 5.4 to 6.1), but its real claim to fame is its veloc-
ity through space. It is one of two stars ejected during a collision of two
binary systems about 2 million years ago in the region where the Orion
Nebula’s Trapezium (see #19) now resides. The other is Mu (μ) Columbae.
A third star, 53 Arietis, originated in that same region, but was ejected a
few million years earlier. AE Aurigae is currently flying by IC 405, illumi-
nating the gas as it goes. Once it passes, the nebula will fade. — A.G.70 M82
M82 — also known as the Cigar Galaxy — and neighboring
M81 (see #92), together make up of the night sky’s dynamic
duos. M82 is one of the closest (12 million light-years)
examples of an edge-on system in starburst chaos. In
images, it appears like an extragalactic radical, with spiked
“hairs” bristling off a cigar-shaped body tattooed with invis-
ible dark matter.
German astronomer Johann Elert Bode discovered this
“nebulous patch” on the same night as M81, noting its elon-
gated form. In 1871, William Parsons, Earl of Rosse, noted
curious dark bands crossing its length. Later astronomers
suspected the galaxy was experiencing violent explosions
— and they were right. We now know its central region is
the site of intense starburst activity, with 40 or so superno-
JOHN CHUMACKvae in the early stages of expansion.
DAN CROWSONTERRY HANCOCK/TOM MASTERSONStarburst galaxies create stars at a rate tens or even
hundreds of times faster than normal galaxies. A brush
with M81 hundreds of millions of years ago triggered this
stellar chaos, making the galaxy five times more luminous
than our Milky Way. In red-sensitive images, long fila-
ments stream out at right angles from the galaxy’s central
region to about 34,000 light-years. Enormous galactic
winds and gas outflows are transporting up to some
50,000 suns of gas and dust into intergalactic space.
Through the telescope, M82 is a stunning sight, like
a ghostly starship, cracked and floating through an
interstellar graveyard. Immediately noticeable is that its
western half is distinctly brighter than the eastern half.
Most impressive are the energetic-looking bursts of star-
light running lengthwise through most of the galaxy. Does
the core look angular to you? If so, it’s an illusion created
by wedgelike lanes of dust. — S.J.O.