NGC 262

NGC 262 (also known as Markarian 348) is a huge spiral galaxy in the cluster LGG 14.[1] It is a Seyfert 2 spiral galaxy located 287 million light years away in the constellation Andromeda.[2] It was discovered on September 17, 1885 by Lewis A. Swift.

NGC 262
SDSS NGC 262 sdss.org
NGC 262 as imaged by the SDSS.
Observation data (J2000 epoch)
ConstellationAndromeda
Right ascension 00h 48m 47.14154s[1]
Declination+31° 57′ 25.08″[1]
Distance287 million light-years (88 Mpc)[2]
Apparent magnitude (V)13.1
Characteristics
TypeS0a
Apparent size (V)1,1' × 1,1'
Other designations
2MASX J00484711+3157249, UGC 499, Markarian 348 [1]

Size

This galaxy has an apparent diameter of approximately 1.3 million light-years, occupying 1.1' of the Earth's sky.[3] It holds approximately 15 trillion stars. NGC 262 was tidally disturbed by the gravitational forces of smaller galaxies, which resulted in its large size.[3]

NGC 262 is very unusual, since it is 10 times larger than a regular spiral galaxy of its type.[2] According to Morris and Wannier, NGC 262 is surrounded by a huge cloud of neutral hydrogen[2] that is probably caused by the tidal stripping of smaller galaxies. The cloud has an apparent mass of approximately 50 billion solar masses[2] at a distance of 88 kiloparsecs (287,000 light-years) [2] from the nucleus of NGC 262 and extending up to 300 kiloparsecs (1 million light-years) away.[2] The cloud is spiral shaped with at least one arm, and possibly another one extending throughout the galaxy.

References

  1. ^ a b c d "SIMBAD query result". Basic data for NGC 262.
  2. ^ a b c d e f g Huchra, J. (May 15, 1980). "The optical properties of the unusual galaxy Markarian 348". The Astrophysical Journal. 238: 11–12. Bibcode:1980ApJ...238L..11H. doi:10.1086/183246.
  3. ^ a b "The New York Times". Distant galaxy found to be largest known. 1987-03-13.
2009 Giro d'Italia

The 2009 Giro d'Italia was the 92nd running of the Giro d'Italia, one of cycling's Grand Tours. It was held from 9 to 31 May 2009, and marked the 100th year since the first edition of the race. Starting in Venice and finishing in Rome, 22 teams competed over 21 stages.

The Giro was raced on a unique path through Italy, taking the peloton to some historic cities and towns in Italian cycling. Though the route lacked any well-known, storied climbs, the many intermediate and mountain stages in the second and third weeks of the race proved deceptively difficult. The 10th and the 16th stages were both called the race's queen stage, as both contained multiple difficult mountain climbs.

Riders protested during the ninth stage, a criterium in Milan. This protest was nominally about the overall safety conditions of the stage, and was sparked by life-threatening injuries sustained by Pedro Horrillo the day before. In the protest, riders declined to contest the stage except for a final sprint finish, a decision that proved controversial with race organizers and fans.

Denis Menchov won the race, having taken the lead in a long time trial in stage 12, and defended vigorously against attacks by his closest challenger, Danilo Di Luca, during the mountain stages of the final week. Di Luca came in second, 41 seconds behind the winner, and won the mauve jersey as points classification winner. Subsequent to the Giro, both he and third-place finisher Franco Pellizotti became embroiled in doping scandals, were given bans, and had their results stripped.

List of largest nebulae

Below is a list of the largest nebulae so far discovered, ordered by size.

Malin 1

Malin 1 is a giant low surface brightness (LSB) spiral galaxy. It is located 1.19 billion light-years (366 Mpc) away in the constellation Coma Berenices, near the North Galactic Pole. As of February 2015, it is arguably the largest known spiral galaxy, with an approximate diameter of 650,000 light-years (200,000 pc), six and a half times the diameter of our Milky Way. It was discovered by astronomer David Malin in 1986 and is the first LSB galaxy verified to exist. Its high surface brightness central spiral is 30,000 light-years (9,200 pc) across, with a bulge of 10,000 light-years (3,100 pc). The central spiral is a SB0a type barred-spiral.Malin 1 is peculiar in several ways: its diameter alone would make it the largest barred spiral galaxy ever to have been observed.Malin 1 was found later to be interacting with two other galaxies, Malin 1B and SDSS J123708.91+142253.2. Malin 1B is located 46,000 light-years (14,000 pc) away from the high surface brightness central spiral of Malin 1, which may be responsible for the formation of the galaxy's central bar. Meanwhile, SDSS J123708.91+142253.2 is located within the huge, faint halo of Malin 1 and might have caused the formation of the extended low surface brightness disc through tidal stripping.

Observations by Galaz et al. in April 2014 revealed a detailed view of the spiral structure of Malin 1 in optical bands. The galaxy exhibits giant and very faint spiral arms, with a thickness of up to one-third the diameter of the Milky Way. Other details, such as possible stellar streams and formation regions, are revealed as well.

NGC 765

NGC 765 is an intermediate spiral galaxy located in the constellation Aries. It is located at a distance of circa 220 million light years from Earth, which, given its apparent dimensions, means that NGC 765 is about 195,000 light years across. It was discovered by Albert Marth on October 8, 1864. The galaxy has an extensive hydrogen (HI) disk with low surface brightness, whose diameter is estimated to be 240 kpc (780,000 light years).

Seyfert galaxy

Seyfert galaxies are one of the two largest groups of active galaxies, along with quasars. They have quasar-like nuclei (very luminous, distant and bright sources of electromagnetic radiation) with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, their host galaxies are clearly detectable.Seyfert galaxies account for about 10% of all galaxies and are some of the most intensely studied objects in astronomy, as they are thought to be powered by the same phenomena that occur in quasars, although they are closer and less luminous than quasars. These galaxies have supermassive black holes at their centers which are surrounded by accretion discs of in-falling material. The accretion discs are believed to be the source of the observed ultraviolet radiation. Ultraviolet emission and absorption lines provide the best diagnostics for the composition of the surrounding material.Seen in visible light, most Seyfert galaxies look like normal spiral galaxies, but when studied under other wavelengths, it becomes clear that the luminosity of their cores is of comparable intensity to the luminosity of whole galaxies the size of the Milky Way.Seyfert galaxies are named after Carl Seyfert, who first described this class in 1943.

UGC 2885

UGC 2885 is a large unbarred spiral galaxy of type SA(rs)c in the constellation Perseus. It is 232 million light-years (71 Mpc) from Earth and is also a possible member of the Pisces-Perseus supercluster.

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