Comet Borrelly or Borrelly's Comet (official designation: 19P/Borrelly) is a periodic comet, which was visited by the spacecraft Deep Space 1 in 2001. The comet last came to perihelion (closest approach to the Sun) on May 28, 2015 and will next come to perihelion on February 1, 2022.[2][1] The comet's nucleus, seen in the adjacent image, is particularly notable for being shaped like a bowling pin.

Comet Borrelly Nucleus
Discovered byAlphonse Borrelly
Discovery dateDecember 28, 1904
1905 II; 1911 VIII; 1918 IV;
1925 VIII; 1932 IV; 1953 IV;
1960 V; 1967 VIII; 1974 VII;
1981 IV; 1987 XXXIII; 1994 XXX
Orbital characteristics
Epoch September 8, 2001 (JD 2452160.5)
Aphelion5.83 AU
Perihelion1.35 AU
(February 1, 2022)[1][2]
3.59 AU
6.8 a
Physical characteristics
Dimensions8×4×4 km[3]
Mean radius
2.4 km[4]
Mass2×1013 kg[5]
Mean density
0.3 g/cm³[6]
AlbedoAlbedo: 0.03[7]


The comet was discovered by Alphonse Borrelly during a routine search for comets at Marseilles, France on December 28, 1904.

Deep Space 1 flyby

Animation of Deep Space 1 trajectory
Animation of Deep Space 1's trajectory from 24 October 1998 to 31 December 2003
   Deep Space 1 ·   9969 Braille ·   Earth ·   19P/Borrelly

On September 21, 2001 the spacecraft Deep Space 1, which was launched to test new equipment in space, performed a flyby of Borrelly. It was steered toward the comet during the extended mission of the craft, and presented an unexpected bonus for the mission scientists. Despite the failure of a system that helped determine its orientation, Deep Space 1 managed to send back to Earth what were, at the time, the best images and other science data from a comet.

Orbits of periodic comets
The orbits of three periodic comets, 1P/Halley, 19P/Borrelly and 153P/Ikeya-Zhang, set against the orbits of the outer planets.


  1. ^ a b MPC
  2. ^ a b Seiichi Yoshida (2014-08-10). "19P/Borrelly". Seiichi Yoshida's Comet Catalog. Retrieved 2014-10-29.
  3. ^ Weaver, H. A.; Stern, S.A.; Parker, J. Wm. (2003). "Hubble Space Telescope STIS Observations of Comet 19P/BORRELLY during the Deep Space 1 Encounter". The American Astronomical Society. 126 (1): 444–451. Bibcode:2003AJ....126..444W. doi:10.1086/375752. Retrieved 2008-12-16.
  4. ^ "Archived copy". Archived from the original on 2014-08-09. Retrieved 2014-08-08.CS1 maint: Archived copy as title (link)
  5. ^ Using the volume of an ellipsoid of 8x4x4km * a rubble pile density of 0.3 g/cm³ yields a mass (m=d*v) of 2.0E+13 kg.
  6. ^ D. T. Britt; G. J. Consol-magno SJ; W. J. Merline (2006). "Small Body Density and Porosity: New Data, New Insights" (PDF). Lunar and Planetary Science XXXVII. Archived (PDF) from the original on 17 December 2008. Retrieved 2008-12-16.
  7. ^ Robert Roy Britt (2001-11-29). "Comet Borrelly Puzzle: Darkest Object in the Solar System". Space.com. Archived from the original on 22 January 2009. Retrieved 2008-12-16.

External links

Numbered comets
19P/Borrelly Next

18D/Perrine–Mrkos is a periodic comet in the Solar System, originally discovered by the American-Argentine astronomer Charles Dillon Perrine (Lick Observatory, California, United States) on December 9, 1896. For some time it was thought to be a fragment of Biela's Comet.It was considered lost after the 1909 appearance, but was rediscovered by the Czech astronomer Antonín Mrkos (Skalnate Pleso Observatory, Slovakia) on October 19, 1955, using ordinary binoculars, it was later confirmed as 18D by Leland E. Cunningham (Leuschner Observatory, University of California, Berkeley).

The comet was last observed during the 1968 perihelion passage when it passed 0.3144 AU (47,030,000 km; 29,230,000 mi) from the Earth. The comet has not been observed during the following perihelion passages:

1975 Aug. 2

1982 May 16

1989 Feb. 28

1995 Dec. 6

2002 Sept.10

2009 Apr. 17

2017 Feb. 26The next predicted perihelion passage would be on 2025-Jan-01 but the comet is currently considered lost as it has not been seen since Jan 1969.

2001 in spaceflight

This article outlines notable events occurring in 2001 in spaceflight, including major launches and EVAs.


20D/Westphal was a periodic comet with an orbital period of 61 years. It fits the classical definition of a Halley-type comet with (20 years < period < 200 years). It was originally discovered by the German astronomer J. G. Westphal (Göttingen, Germany) on July 24, 1852.

It was independently discovered by the American astronomer Christian Heinrich Friedrich Peters (Constantinople) on August 9.

The comet was last seen between September 27 and November 26, 1913, first by Pablo T. Delavan (La Plata Astronomical Observatory) and then others. It was predicted to return in 1976 but was never observed, and is now considered a lost comet.


276P/Vorobjov (previously P/2012 T7 (VOROBJOV)) is a Jupiter-family comet discovered on 15 October 2012 by Tomáš Vorobjov on three 120-s images taken remotely using the 0.81-m f/7 Ritchey-Chretien Schulman Telescope located at the Mt. Lemmon SkyCenter via the Sierra Stars Observatory Network in the course of a minor-planet search survey undertaken as part of the International Astronomical Search Collaboration (IASC) school campaigns. After posting on the Minor Planet Center's NEOCP webpage, other observers have commented on the object's cometary appearance. The discovery was announced by the Minor Planet Center on 18 October, three days after the discovery.

3352 McAuliffe

3352 McAuliffe (), provisional designation 1981 CW, is a rare-type asteroid and suspected binary system, classified as near-Earth object of the Amor group, approximately 2 kilometers in diameter. It was discovered on 6 February 1981, by American astronomer Norman Thomas at Lowell's Anderson Mesa Station near Flagstaff, Arizona, United States.Originally, this asteroid was the target of the 1998 Deep Space 1 mission, but that mission was eventually rerouted to 9969 Braille. It was named in memory of Challenger crew member Christa McAuliffe.

9969 Braille

9969 Braille, provisional designation 1992 KD, is an eccentric, rare-type and elongated asteroid from the innermost regions of the asteroid belt, classified as Mars-crosser and slow rotator, approximately 1–2 kilometers in diameter. It was discovered in 1992, by astronomers at Palomar observatory and later named after Louis Braille, the inventor of the writing system for the blind. It was photographed in closeup by the spacecraft Deep Space 1 in 1999, but a malfunction resulted in indistinct images.

Alphonse Borrelly

Alphonse Louis Nicolas Borrelly (December 8, 1842 – February 28, 1926) was a French astronomer.

He joined the Marseille Observatory in 1864. In the course of his career, he discovered a number of asteroids and comets, including the periodic comet 19P/Borrelly.

The French Academy of Sciences awarded him the Prix Valz (Prix Valz) for 1903 and the Prix Lalande for 1909. The asteroid 1539 Borrelly was named in his honor.

In 1913, he received the Prix Jules Janssen, the highest award of the Société astronomique de France, the French astronomical society.

C/2012 E2 (SWAN)

Comet C/2012 E2 (SWAN) was a Kreutz group sungrazing comet discovered by Vladimir Bezugly in publicly available images taken by the SWAN instrument (Solar Wind ANisotropies) on board the SOHO spacecraft. It is recognized for being the first Kreutz sungrazer observed in SWAN imagery.

C/2015 F3

Comet C/2015 F3 (SWAN) was discovered in March 2015 by Rob Matson, Vladimir Bezugly and Michael Matiazzo in near real time images taken by the SWAN instrument aboard the SOHO spacecraft. At discovery the comet was already shining at around 10th magnitude as it was already near perihelion

. Orbital studies revealed C/2015 F3 to be a related fragment to long periodic comets C/1988 A1 (Liller) and C/1996 Q1 (Tabur), which were already thought to have broken off each other at a previous perihelion passage. As of May 2015, Comet SWAN was fading rapidly, as both C/1988 A1 and C/1996 Q1 ultimately did. .

C/2015 F5 (SWAN-XingMing)

Comet C/2015 F5 (SWAN-XingMing) was discovered on March 29, 2015 in near real time SWAN images of the SOHO spacecraft, by Szymon Liwo and Worachate Boonplod. It was also independently discovered on April 4, 2015 by Guoyou Sun and Gao Xing at the XingMing observatory near Ürümqi, China. At discovery, the comet had just passed perihelion and was only 0,35 AU from the Sun, shining at about +10 mag. As of May 2015 the comet had faded below mag +13. The comet is periodic with an orbital period of about 61 years .


A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred metres to tens of kilometres across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times the Earth's diameter, while the tail may stretch one astronomical unit. If sufficiently bright, a comet may be seen from the Earth without the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures.

Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several millions of years. Short-period comets originate in the Kuiper belt or its associated scattered disc, which lie beyond the orbit of Neptune. Long-period comets are thought to originate in the Oort cloud, a spherical cloud of icy bodies extending from outside the Kuiper belt to halfway to the nearest star. Long-period comets are set in motion towards the Sun from the Oort cloud by gravitational perturbations caused by passing stars and the galactic tide. Hyperbolic comets may pass once through the inner Solar System before being flung to interstellar space. The appearance of a comet is called an apparition.

Comets are distinguished from asteroids by the presence of an extended, gravitationally unbound atmosphere surrounding their central nucleus. This atmosphere has parts termed the coma (the central part immediately surrounding the nucleus) and the tail (a typically linear section consisting of dust or gas blown out from the coma by the Sun's light pressure or outstreaming solar wind plasma). However, extinct comets that have passed close to the Sun many times have lost nearly all of their volatile ices and dust and may come to resemble small asteroids. Asteroids are thought to have a different origin from comets, having formed inside the orbit of Jupiter rather than in the outer Solar System. The discovery of main-belt comets and active centaur minor planets has blurred the distinction between asteroids and comets. In the early 21st century, the discovery of some minor bodies with long-period comet orbits, but characteristics of inner solar system asteroids, were called Manx comets. They are still classified as comets, such as C/2014 S3 (PANSTARRS). 27 Manx comets were found from 2013 to 2017.As of July 2018 there are 6,339 known comets, a number that is steadily increasing as they are discovered. However, this represents only a tiny fraction of the total potential comet population, as the reservoir of comet-like bodies in the outer Solar System (in the Oort cloud) is estimated to be one trillion. Roughly one comet per year is visible to the naked eye, though many of those are faint and unspectacular. Particularly bright examples are called "great comets". Comets have been visited by unmanned probes such as the European Space Agency's Rosetta, which became the first ever to land a robotic spacecraft on a comet, and NASA's Deep Impact, which blasted a crater on Comet Tempel 1 to study its interior.

Comet Borrelly

Comet Borrelly may mean:

The numbered periodic comet 19P/Borrelly (a.k.a. 19P/1904 Y2, 1905 II, 1904e, 19P/1911 S1, 1911 VIII, 1911e, 1918 IV, 1918c 1925 VIII, 1925f, 1932 IV, 1932i, 1953 IV, 1954b, 1960 V, 1960k, 1967 VIII, 1967m, 1974 VII, 1973m, 1981 IV, 1980i, 1987 XXXIII, 1987p, 1994 XXX, 1994l)

Or any of these long-period comets:

C/1873 Q1 (a.k.a. 1873 IV, 1873c)

C/1874 O1 (a.k.a. 1874 V, 1874d)

C/1874 X1 (a.k.a. 1874 VI, 1874f)

C/1877 C1 (a.k.a. 1877 I, 1877a)

C/1889 X1 (a.k.a. 1890 I, 1889g)

C/1903 M1 (a.k.a. 1903 IV, 1903c)

C/1912 V1 (a.k.a. 1912 III, 1912c)

It could also be a partial reference to these comets:

C/1900 O1, Comet Borrelly-Brooks (a.k.a. 1900 II, 1900b)

C/1909 L1, Comet Borrelly-Daniel (a.k.a. 1909 I, 1909a)

Comet nucleus

The nucleus is the solid, central part of a comet, popularly termed a dirty snowball or an icy dirtball. A cometary nucleus is composed of rock, dust, and frozen gases. When heated by the Sun, the gases sublimate and produce an atmosphere surrounding the nucleus known as the coma. The force exerted on the coma by the Sun's radiation pressure and solar wind cause an enormous tail to form, which points away from the Sun. A typical comet nucleus has an albedo of 0.04. This is blacker than coal, and may be caused by a covering of dust.Results from the Rosetta and Philae spacecraft show that the nucleus of 67P/Churyumov–Gerasimenko has no magnetic field, which suggests that magnetism may not have played a role in the early formation of planetesimals. Further, the ALICE spectrograph on Rosetta determined that electrons (within 1 km (0.62 mi) above the comet nucleus) produced from photoionization of water molecules by solar radiation, and not photons from the Sun as thought earlier, are responsible for the degradation of water and carbon dioxide molecules released from the comet nucleus into its coma. On 30 July 2015, scientists reported that the Philae spacecraft, that landed on comet 67P/Churyumov-Gerasimenko in November 2014, detected at least 16 organic compounds, of which four (including acetamide, acetone, methyl isocyanate and propionaldehyde) were detected for the first time on a comet.


DS1 or DS-1 may refer to:

BOSS DS-1, a guitar distortion pedal

Digital Signal 1, a T-carrier signaling scheme devised by Bell Labs

Deep Space 1, a mission to 9969 Braille & 19P/Borrelly

DS-1 (drug), a selective GABAA α4β3δ agonist drug

South African Class DS1, a diesel locomotive class

Datsun DS-1, a car by Nissan, see Datsun DS Series

Dark souls 1. A playstation 3 video game

Deep Space 1

Deep Space 1 (DS1) was a NASA technology demonstration spacecraft which flew by an asteroid and a comet. It was part of the New Millennium Program, dedicated to testing advanced technologies.

Launched on 24 October 1998, the Deep Space 1 spacecraft carried out a flyby of asteroid 9969 Braille, which was its primary science target. The mission was extended twice to include an encounter with comet 19P/Borrelly and further engineering testing. Problems during its initial stages and with its star tracker led to repeated changes in mission configuration. While the flyby of the asteroid was only a partial success, the encounter with the comet retrieved valuable information. Three of twelve technologies on board had to work within a few minutes of separation from the carrier rocket for the mission to continue.

The Deep Space series was continued by the Deep Space 2 probes, which were launched in January 1999 piggybacked on the Mars Polar Lander and were intended to strike the surface of Mars (though contact was lost and the mission failed). Deep Space 1 was the first NASA spacecraft to use ion propulsion rather than the traditional chemical-powered rockets.

List of Solar System probes

This is a list of space probes that have left Earth orbit (or were launched with that intention but failed), organized by their planned destination. It includes planetary probes, solar probes, and probes to asteroids and comets, but excludes lunar missions, which are listed separately at List of lunar probes and List of Apollo missions. Flybys (such as gravity assists) that were incidental to the main purpose of the mission are also included. Flybys of Earth are listed separately at List of Earth flybys. Confirmed future probes are included, but missions that are still at the concept stage, or which never progressed beyond the concept stage, are not.

List of missions to comets

As of 2013, the United States, Soviet Union, Japan and the European Space Agency have conducted missions to comets.

Orbital Sciences Corporation

Orbital Sciences Corporation (commonly referred to as Orbital) was an American company specializing in the design, manufacture and launch of small- and medium- class space and rocket systems for commercial, military and other government customers. In 2014 Orbital merged with Alliant Techsystems to create a new company called Orbital ATK, Inc., which in turn was purchased by Northrop Grumman in 2018.

Orbital was headquartered in Dulles, Virginia and publicly traded on the New York Stock Exchange with the ticker symbol ORB. Orbital’s primary products were satellites and launch vehicles, including low-Earth orbit, geosynchronous-Earth orbit and planetary spacecraft for communications, remote sensing, scientific and defense missions; ground- and air-launched rockets that delivered satellites into orbit; missile defense systems that were used as interceptor and target vehicles; and human-rated space systems for Earth-orbit, lunar and other missions. Orbital also provided satellite subsystems and space-related technical services to government agencies and laboratories.On April 29, 2014, Orbital Sciences announced that it would merge with Alliant Techsystems to create a new company called Orbital ATK, Inc. The merger was completed on February 9, 2015 and Orbital Sciences ceased to exist as an independent entity. On September 18, 2017, Northrop Grumman announced plans to purchase Orbital ATK for $7.8 billion in cash plus assumption of $1.4 billion in debt. Orbital ATK shareholders approved the buyout on November 29, 2017. The FTC approved the acquisition with conditions on June 5, 2018, and one day later, Orbital ATK were absorbed and became Northrop Grumman Innovation Systems.

Uncrewed spacecraft

Uncrewed or unmanned spacecraft are spacecraft without people on board, used for robotic spaceflight. Uncrewed spacecraft may have varying levels of autonomy from human input; they may be remote controlled, remote guided or even autonomous, meaning they have a pre-programmed list of operations, which they will execute unless otherwise instructed. Many habitable spacecraft also have varying levels of robotic features. For example, the space stations Salyut 7 and Mir, and the ISS module Zarya were capable of remote guided station-keeping, and docking maneuvers with both resupply craft and new modules. The most common uncrewed spacecraft categories are robotic spacecraft, uncrewed resupply spacecraft, space probes and space observatories. Not every uncrewed spacecraft is a robotic spacecraft; for example, a reflector ball is a non-robotic uncrewed spacecraft.

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.