Re: [Chine] Systèmes anti-satellites

[Elixir]

http://news.yahoo.com/china-missile-hit-highest-suborbital-level-since-1976-053335882.html

WASHINGTON (Reuters) - China launched a large missile on Monday that reached 6,200 miles above the earth, its highest suborbital launch since 1976, according to a U.S. scientist at Harvard University.

Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, said the rocket was launched from the Xichang Satellite Launch Center in western China, and China said the rocket carried a science payload which studied the earth's magnetosphere.

He said the rocket could possibly be used in the future to carry an anti-satellite payload on a similar trajectory, but there was no evidence to indicate the launch was intended to test such a capability.

The United States remains concerned about China's development of anti-satellite capabilities after it shot a missile at one of its own defunct satellites in orbit in 2007, creating an enormous amount of debris in space.

Monday's rocket launch was similar to launches using the Blue Scout Junior rocket that were conducted by the U.S. Air Force in the 1960s for research on the Earth's magnetosphere, McDowell said in an emailed response to questions.

The launch came less than a week after U.S. Deputy Defense Secretary Ashton Carter unveiled what he called a "long overdue" effort to safeguard U.S. national security satellites and develop ways to counter the space capabilities of potential adversaries.

The Pentagon also released an 83-page report on Chinese military developments that highlighted China's increasing space capabilities and said Beijing was pursuing a variety of activities aimed at preventing its adversaries from using space-based assets during a crisis.

A Pentagon spokesman declined to comment on the Chinese rocket launch.

(Reporting By Andrea Shalal-Esa; Editing by Mohammad Zargham and Ron Popeski)

:study:

[Paolo]

Une petite question, le dernier chiffre ca a l'air d'etre l'altitude en pied ? merci pour les infos quand meme :)

c'est l'apogée en km

[Starking]

Une petite question, le dernier chiffre ca a l'air d'etre l'altitude en pied ? merci pour les infos quand meme :)

c'est l'apogée en km

Effectivement. Les USA ont utilisé des fusées-sondes Blue Scout Jr (Castor/Antares/Alcor/Cetus) dans les années 1960. Elles ont dépassé plusieurs fois 10 000 km d'altitude.
Les deux Scout qui ont dépassé 10 000 km dans les années 1970 étaient semblables aux lanceurs Scout (Algol/Castor/Antares/Altair). Celle de 1971 a été lancée pour le compte de l'Allemagne. Celle de 1976 n'était pas vraiment une fusée-sonde dans la mesure où elle n'a pas servi à sonder l'environnement terrestre ; elle a servi à vérifier certains aspects de la théorie de la relativité (voir Gravity Probe A).
Mais, de nos jours, je ne vois pas l'intérêt d'un vol suborbital à 10 000 km pour une expérience scientifique.

[Elixir]

Quelques réactions côté américain -

(Reuters) - The U.S. government believes a Chinese missile launch this week was the first test of a new interceptor that could be used to destroy a satellite in orbit, one U.S. defense official told Reuters on Wednesday.

China launched a rocket into space on Monday but no objects were placed into orbit, the Pentagon said on Wednesday. The object re-entered Earth's atmosphere above the Indian Ocean.

"We tracked several objects during the flight but did not observe the insertion of any objects into orbit and no objects associated with this launch remain in space," said Lieutenant Colonel Monica Matoush, a Pentagon spokeswoman.

The rocket reached 10,000 km (6,250 miles) above Earth, the highest suborbital launch seen worldwide since 1976, according to Jonathan McDowell at the Harvard-Smithsonian Center for Astrophysics.

http://www.airforcemag.com/DRArchive/Pages/2013/May%202013/May%2016%202013/Chinese-Anti-Satellite-Test.aspx

Asked for comment, Pentagon spokeswoman Lt. Col Monica Matoush told the Daily Report on Wednesday: "We detected a launch on May 13 from within China. The launch appeared to be on a ballistic trajectory nearly to geosynchronous Earth orbit. We tracked several objects during the flight, but did not observe the insertion of any objects into orbit and no objects associated with this launch remain in space."

statement of the US Defense Dept.

"We detected a launch on May 13 from within China. The launch appeared to be on a ballistic trajectory nearly to geosynchronous Earth orbit. We tracked several objects during the flight but did not observe the insertion of any objects into orbit and no objects associated with this launch remain in space.

"Based upon observations, we assess that the objects reentered the atmosphere above the Indian Ocean. We defer any further questions to the government of China."

Côté japonais, le Secrétaire général du Cabinet Yoshihide Suga dit que le Japon "a formulé une demande solennelle par voie diplomatique pour exiger une explication de la part du gouvernement chinois".

Sur le forum NSF par jcm -

http://forum.nasaspaceflight.com/index.php?topic=31898.45
Apparently there is a Pentagon statement that they tracked the launch to "nearly geostationary altitude" and that the associated objects were on a path that would dump them in the Indian Ocean. (got this from a reporter, haven't seen the original statement - does anyone have a link?)

So if their tracking is correct, we are looking at a circa 30000 km apogee and an 8 to 9 hour flight.

Sur un forum spécialisé aérospatial chinois 9ifly (NSF prend souvent des informations dans ce forum chinois), l'un des intervenants suppose qu'il existe 2 possibilités pour ce tir -

1. Aller à l'orbite de parking LEO, glisser ensuite à l'orbite au-dessus de l'équateur avant d'atteindre la GTO.

2. Accès direct à l'orbite de transfert elliptique dont le plan orbital est en intersection avec la GEO.

Un autre intervenant chinois du forum dit que justement il avait donné un cours en mécanique pour les BAC+1 à la fac l'année dernière et il avait fait faire un exercice de nature similaire -





D'après eux, il semble que ce soit le 2ème scénario qui s'est produit avec ce tir du 13 Mai.

:study:

[Elixir]

Le calcul de la zone de chute et la trajectoire par l'intervenant chinois (celui qui donne des cours à la fac) au forum 9ifly, c'est conforme par rapport à l'observation américaine -



D'après ses calculs, le point de chute se situe vers 98°E 28°S, à 1600km à l'ouest de l'Australie, dans l'océan indien.

:study:

[David L.]

Selon le Pentagone, la Chine déploierait un laser anti-satellites en orbite basse d'ici 2020.

https://freebeacon.com/national-security/dia-china-to-deploy-asat-laser-by-2020/

[Elixir]

Anti-satellite : la Chine s'arme avec du laser et des missiles ?

Plusieurs rapports de renseignement américains ont révélé un calendrier très cadencé sur la mise en service des armes anti-satellite par la Chine. Tour horizon.

http://www.eastpendulum.com/anti-satellite-la-chine-sarme-avec-du-laser-et-des-missiles

Henri K.