:Epsilon (rocket)
{{Short description|JAXA small-lift rocket family}}
{{Use American English|date=September 2021}}
{{Use dmy dates|date=September 2021}}
{{Infobox rocket
| name = Epsilon
| image = Epsilon rocket F2.jpg
| caption = Epsilon flight F2 before launch in December 2016
| function = Launch vehicle
| manufacturer =
| country-origin = Japan
| height = 24.4 m (Demonstration Flight)
26 m (Enhanced)
27.2 m (Epsilon S){{cite web |title=イプシロンSロケット開発状況に関する説明会 |trans-title=Press Briefing on the development status of the Epsilon S rocket |url=https://www.jaxa.jp/projects/files/youtube/epsilon-s/epsilon-s_doc_20230707.pdf |publisher=JAXA |access-date=16 March 2024 |language=Japanese |date=7 July 2023}}
| diameter = 2.5 m
| mass = 91 t (Demonstration Flight)
95.4 t (Enhanced)
~100 t (Epsilon S)
| stages = 3–4
| capacities = {{Infobox rocket/payload
| location = 250 x 500 km orbit
Standard 3 stages configuration
| kilos = {{cvt|1500|kg}}
}}
{{Infobox rocket/payload
| location = 500 km orbit
Optional 4 stages configuration
| kilos = {{cvt|700|kg}}
}}
{{Infobox rocket/payload
| location = 500 km orbit
Epsilon S
}}
{{Infobox rocket/payload
| location = 500 km SSO
Optional 4 stages configuration
| kilos = {{cvt|590|kg}}
}}
{{Infobox rocket/payload
| location = 700 km SSO
Epsilon S
}}
| status = Active
| sites = Uchinoura
| launches = 6
| success = 5
| fail = 1
| partial = 0
| first = 14 September 2013
| last = 12 October 2022
| stagedata = {{Infobox rocket/stage
| type = stage
| stageno = First
| diff = Demonstration Flight/Enhanced
| name = SRB-A3
| engines = 1 solid
| thrust = {{cvt|2271|kN}}{{Cite web |url=http://www.jaxa.jp/press/2013/04/20130405_epsilon.pdf|title=イプシロンロケットの開発および準備状況|publisher=JAXA |access-date=September 16, 2013}}
| SI = {{convert|284|isp|abbr=on}}
| burntime = 116 seconds
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = First
| diff = Epsilon S
| name = SRB-3
| engines = 1 solid
| SI = {{convert|283.6|isp|abbr=on}}
| burntime = 105 seconds
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Second
| diff = Demonstration Flight
| name = M-34c
| engines = 1 solid
| SI = {{convert|300|isp|abbr=on}}
| burntime = 105 seconds
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Second
| diff = Enhanced
| name = M-35
| engines = 1 solid
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Second
| diff = Epsilon S
| engines = 1 solid
| SI = {{convert|294.5|isp|abbr=on}}
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Third
| diff = Demonstration Flight
| name = KM-V2b
| engines = 1 solid
| SI = {{convert|301|isp|abbr=on}}
| burntime = 90 seconds
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Third
| diff = Enhanced
| name = KM-V2c
| engines = 1 solid
| SI = {{convert|299|isp|abbr=on}}
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Third
| diff = Epsilon S
| engines = 1 solid
| SI = ~{{convert|295|isp|abbr=on}}
| fuel =
}}
{{Infobox rocket/stage
| type = stage
| stageno = Fourth
| diff = Optional
| name = CLPS
| engines =
| thrust = {{cvt|40.8|N}}
| SI = {{convert|215|isp|abbr=on}}
| burntime = 1100 seconds (maximum)
| fuel = Hydrazine
}}
}}
The Epsilon Launch Vehicle, or {{nihongo|Epsilon rocket|イプシロンロケット|Ipushiron roketto}} (formerly Advanced Solid Rocket), is a Japanese solid-fuel rocket designed to launch scientific satellites. It is a follow-on project to the larger and more expensive M-V rocket which was retired in 2006. The Japan Aerospace Exploration Agency (JAXA) began developing the Epsilon in 2007. It is capable of placing a 590 kg payload into Sun-synchronous orbit.{{cite web|url=http://www.jaxa.jp/projects/pr/brochure/pdf/01/rocket07.pdf |title=Epsilon Launch Vehicle|publisher=JAXA|access-date=25 January 2018}}
Vehicle description
The development aim is to reduce the US$70 million launch cost of an M-V;{{cite news|url=http://www.spaceflightnow.com/news/n1008/11japan/|title=Asteroid probe, rocket get nod from Japanese panel|publisher=Spaceflight Now|date=August 11, 2010|access-date=October 29, 2012}} the Epsilon costs US$38 million per launch.{{cite web|last=Clark|first=Stephen|url=http://www.spaceflightnow.com/epsilon/sprinta/130914launch/#.UjSh0cbkt8E|title=Japan's 'affordable' Epsilon rocket triumphs on first flight |publisher=Spaceflight Now|date=September 14, 2013|access-date=September 16, 2013}} Development expenditures by JAXA exceeded US$200 million.
To reduce the cost per launch the Epsilon uses the existing SRB-A3, a solid rocket booster on the H-IIA rocket, as its first stage. Existing M-V upper stages will be used for the second and third stages, with an optional fourth stage available for launches to higher orbits. The J-I rocket, which was developed during the 1990s but abandoned after just one launch, used a similar design concept, with an H-II booster and Mu-3S-II upper stages.{{cite web|url=http://www.jaxa.jp/projects/rockets/j1/index_e.html|title=J-I Launch Vehicle|date=2007|publisher=Japan Aerospace Exploration Agency|access-date=11 July 2015|archive-date=18 August 2012|archive-url=https://web.archive.org/web/20120818072733/http://www.jaxa.jp/projects/rockets/j1/index_e.html|url-status=dead}}
The Epsilon is expected to have a shorter launch preparation time than its predecessors;{{cite web|url=http://www.jaxa.jp/projects/rockets/epsilon/index_e.html|title=Epsilon launch vehicle|publisher=JAXA|access-date=October 29, 2012|archive-date=21 January 2013|archive-url=https://web.archive.org/web/20130121050940/http://www.jaxa.jp/projects/rockets/epsilon/index_e.html|url-status=dead}}{{cite journal|url=https://archive.ists.or.jp/upload_pdf/2009-g-18.pdf|title=Advanced Solid Rocket Launcher and its Evolution |author1=Yasuhiro Morita|author2=Takayuki Imoto|author3=Hiroto Habu|author4=Hirohito Ohtsuka|author5=Keiichi Hori|author6=Takemasa Koreki|author7=Apollo Fukuchi|author8=Yasuyuki Uekusa|author9=Ryojiro Akiba |date=July 10, 2009|journal=27th International Symposium on Space Technology and Science}}{{cite journal |url=https://archive.ists.or.jp/upload_pdf/2009-g-21.pdf|title=A minimized facility concept of the Advanced Solid Rocket launch operation|author1=Kazuyuki Miho|author2=Toshiaki Hara|author3=Satoshi Arakawa|author4=Yasuo Kitai|author5=Masao Yamanishi|date=July 10, 2009|journal=27th International Symposium on Space Technology and Science}} a function called "mobile launch control" greatly shortens the launch preparation time, and needs only eight people at the launch site,{{cite journal | last1=Zhao | first1=Long | last2=Xin | first2=Chao-Jun | last3=Shi | first3=Mei-Ling | last4=Yang | first4=Chen | last5=Wang | first5=Huai-Peng | title=Current Status of Research on Space Emergency Launch | journal=Journal of Physics: Conference Series| volume=1510 | issue=1 | date=1 March 2020 | issn=1742-6588 | doi=10.1088/1742-6596/1510/1/012023|doi-access=free|url=https://www.researchgate.net/publication/341570912 | page=012023| bibcode=2020JPhCS1510a2023Z }} See figure 6 compared with 150 people for earlier systems.{{cite web|url=http://www.ibtimes.co.uk/articles/506050/20130914/japan-rocket-blast-computer-controlled-epsilon.htm|url-status=live|archive-url=https://web.archive.org/web/20130923001416/http://www.ibtimes.co.uk/articles/506050/20130914/japan-rocket-blast-computer-controlled-epsilon.htm|archive-date=23 September 2013|last=Keating|first=Fiona|title=Japan's Laptop-Controlled Space Rocket Blasts Off (video)|work=International Business Times|date=14 September 2013 }}
The rocket has a mass of {{cvt|91|t}} and is {{cvt|24.4|m}} tall and {{cvt|2.5|m}} in diameter.{{cite news|url=http://www.japantimes.co.jp/text/nn20121109a9.html|title=JAXA readies small rocket to break cost, use barriers|newspaper=Japan Times|date=November 9, 2012|access-date=December 2, 2012}}[http://www.spaceflight101.com/epsilon-launch-vehicle-information.html Epsilon Launch Vehicle Information]
= Enhanced version =
After the successful launch of the Epsilon first flight (demonstration flight), the improvement plan was decided to handle the planned payloads (ERG and ASNARO-2).{{cite web|url=http://www.mext.go.jp/b_menu/shingi/gijyutu/gijyutu2/059/shiryo/__icsFiles/afieldfile/2014/11/10/1353006_2.pdf|title=強化型イプシロンロケット プロジェクト移行審査の結果について |date=October 30, 2014|access-date=July 9, 2015}}
Requirements for the improvement:
- Apogee ≧ 28700 km (summer launch), ≧ 31100 km (winter launch) of a 365 kg payload
- Sun-synchronous orbit (500 km) of a ≧ 590 kg payload
- Larger fairing
- Height: 26.0 m
- Diameter: 2.5 m
- Mass: 95.1 t (Standard) / 95.4 t (optional 4th stage (post-boost stage))
Catalog performance according to IHI Aerospace:{{cite web|url=https://www.ihi.co.jp/ia/en/download/i/IHI_Epsilon.pdf|title=EPSILON a solid propellant launch vehicle for new age |publisher=IHI Aerospace|access-date=25 January 2018|archive-url=https://web.archive.org/web/20180125193622/https://www.ihi.co.jp/ia/en/download/i/IHI_Epsilon.pdf|archive-date=25 January 2018}}
- Low Earth orbit 250 km × 500 km for 1.5 t
- Sun-synchronous orbit 500 km × 500 km for 0.6 t
Final characteristics:{{cite web|url=http://fanfun.jaxa.jp/jaxatv/files/20161124_epsilon.pdf|script-title=ja:イプシロンロケットについて|publisher=JAXA |language=ja|date=24 November 2016|access-date=25 January 2018}}
- Height: 26.0 m
- Diameter: 2.6 m (max), 2.5 m (fairing)
- Mass: 95.4 t (standard) / 95.7 t (optional)
= Epsilon S =
Epsilon's first stage has been the modified SRB-A3 which is the solid-rocket booster of H-IIA. As the H-IIA is to be decommissioned and to be replaced by H3, Epsilon is to be replaced by a new version, named Epsilon S.
Major changes of Epsilon S from Epsilon are:
- The first stage is based on SRB-3, the strap-on solid-rocket booster of H3.
- The third stage is a new design, whereas Epsilon's third stage was based on the M-V's third stage. New third stage is three-axis stabilized using Post-Boost Stage (PBS), whereas Epsilon's third stage was spin-stabilized. Also the third stage is outside the fairing, whereas Epsilon's fairing covered the third stage.
- The Epsilon S Post-Boost Stage is mandatory, whereas Epsilon's PBS was optional.
Planned performance of Epsilon S is:
- Sun-synchronous orbit (350 – 700 km): ≧ 600 kg
- Low Earth orbit (500 km): ≧ 1400 kg
The first launch of Epsilon S is planned in 2023.
On July 14, 2023, the solid-fuelled second stage of Epsilon S failed during a test firing.{{Cite web |title=Japanese space agency's Epsilon small rocket engine explodes in test |url=https://english.kyodonews.net/news/2023/07/ddbdbcf86427-japanese-space-agencys-epsilon-small-rocket-engine-explodes-in-test.html |access-date=2024-11-26 |website=Kyodo News+}} The root cause was determined to be the "melting and scattering of a metal part from the ignition device", which damaged the propellant and insulation.{{Cite web |date=2023-12-13 |title=JAXA Identifies Cause of Explosion during Rocket Engine Test |url=https://japannews.yomiuri.co.jp/science-nature/science/20231213-155452/ |access-date=2024-11-26 |website=japannews.yomiuri.co.jp |language=en}} Corrective measures were implemented and the stage was tested again on November 26, 2024; however, the second test also resulted in a failure 49 seconds after ignition.{{Cite news |last=Yamaguchi |first=Mari |date=November 26, 2024 |title=The engine of Japan’s flagship new small rocket explodes during a test for a second time |url=https://apnews.com/article/japan-rocket-engine-fire-explosion-c58b6bd86941f916bb5fb873c645c519 |work=AP News}}
Launch statistics
= Launch outcomes =
{{ #invoke:Chart | bar chart
| float = center
| width = 420
| height = 320
| stack = 1
| group 1 = 0:0:0:0:0:0:0:0:0:1
| group 2 = 0:0:0:0:0:0:0:0:0:0
| group 3 = 1:0:0:1:0:1:1:0:1:0
| group 4 = 0:0:0:0:0:0:0:0:0:0
| colors = FireBrick: Orange: ForestGreen: LightBlue
| group names = Failure: Partial failure: Success: Planned
| x legends = 2013: '14: '15: '16: '17: '18: '19: 2020: '21: '22
| y tick marks = 1
}}
Launch history
Epsilon launch vehicles are launched from a pad at the Uchinoura Space Center previously used by Mu launch vehicles. The maiden flight, carrying the SPRINT-A scientific satellite, lifted off at 05:00 UTC (14:00 JST) on 14 September 2013. The launch was conducted at a cost of US$38 million.{{cite web |url=http://ajw.asahi.com/article/behind_news/social_affairs/AJ201309140070|title=eepsilon rocket all aces this time|publisher=Asahi Shimbun|access-date=September 14, 2013|url-status=dead|archive-url=https://web.archive.org/web/20130923012212/http://ajw.asahi.com/article/behind_news/social_affairs/AJ201309140070|archive-date=September 23, 2013}}
On 27 August 2013, the first planned launch of the launch vehicle had to be aborted 19 seconds before liftoff because of a botched data transmission. A ground-based computer had tried to receive data from the launch vehicle 0.07 seconds before the information was actually transmitted.{{cite web|url=http://www.japantimes.co.jp/news/2013/09/09/national/launch-rehearsed-for-new-rocket/#.UjRVfRb1s08|title=Launch rehearsed for new rocket|newspaper=Japan Times|date=9 September 2013 |access-date=September 14, 2013}}
The initial version of Epsilon has a payload capacity to low Earth orbit of up to 500 kilograms,{{cite web|url=http://www.jaxa.jp/article/interview/vol58/index_e.html|title=Interview: Yasuhiro Morita, Project Manager, Epsilon Launch Vehicle|publisher=JAXA|access-date=October 29, 2012|archive-date=23 November 2012|archive-url=https://web.archive.org/web/20121123052200/http://www.jaxa.jp/article/interview/vol58/index_e.html|url-status=dead}}{{cite news|url=http://spaceflightnow.com/news/n1211/05epsilon/|title=Japan schedules launch of innovative Epsilon rocket|author=Stephen Clark|publisher=Spaceflight Now|date=November 5, 2012|access-date=November 8, 2012}} with the operational version expected to be able to place {{cvt|1200|kg}} into a {{cvt|250|by|500|km}} orbit, or {{cvt|700|kg}} to a circular orbit at {{cvt|500|km}} with the aid of a hydrazine fueled stage.
File:Epsilon Launch Vehicle Model.jpg
Planned launches
Sources: Japanese Cabinet{{cite web |url=https://www8.cao.go.jp/space/plan/plan2/kaitei_fy05/kaitei_fy0512.pdf |title=宇宙基本計画⼯程表 (令和５年度改訂) |trans-title=Basic Plan on Space Policy (2023 Revision) |page=45 |publisher=Cabinet Office |date=22 December 2023 |access-date=26 December 2023 |language=ja |archive-date=25 December 2023 |archive-url=https://web.archive.org/web/20231225105156/https://www8.cao.go.jp/space/plan/plan2/kaitei_fy05/kaitei_fy0512.pdf |url-status=live}}
Internet data leak
In November 2012, JAXA reported that there had been a possible leak of rocket data due to a computer virus. JAXA had previously been a victim of cyber-attacks, possibly for espionage purposes.{{cite news|url=https://www.theregister.co.uk/2012/11/30/jaxa_data_loss/|title=Malware slurps rocket data from Japanese space agency|author=Iain Thomson|newspaper=The Register|date=November 30, 2012 |access-date=December 2, 2012}} Solid-fuel rocket data potentially has military value, and Epsilon is considered as potentially adaptable to an intercontinental ballistic missile.{{cite news|url=http://www.nationaljournal.com/global-security-newswire/japan-s-new-military-buildup-seen-as-response-to-north-korea-china-20130823|title=Japan's New Military Buildup Seen as Response to North Korea, China|newspaper=National Journal|date=23 August 2013|access-date=24 September 2013}} The Japan Aerospace Exploration Agency removed the infected computer from its network, and said its M-V rocket and H-IIA and H-IIB rockets may have been compromised.{{cite news|url=http://www.3news.co.nz/Japans-space-agency-probes-possible-data-leak/tabid/1160/articleID/278923/Default.aspx
|publisher=3 News NZ|title=Virus hits Japan space programme|date=December 3, 2012|access-date= December 2, 2012|archive-url=https://web.archive.org/web/20130922235440/http://www.3news.co.nz/Japans-space-agency-probes-possible-data-leak/tabid/1160/articleID/278923/Default.aspx|archive-date=September 22, 2013|url-status=dead}}
See also
{{Portal|Spaceflight}}
References
External links
{{commons category|Epsilon (space launch vehicle)}}
- [http://global.jaxa.jp/projects/rockets/epsilon/ Epsilon launch vehicle], JAXA
- [http://www.oreilly.co.jp/special/epsilon/ Epsilon Photobook "EPSILON THE ROCKET"]
- {{YouTube|id=JjZLTQev6Vs|title=イプシロンロケット2号機/The Second Epsilon Launch Vehicle}}
- [https://www.ihi.co.jp/ia/en/products/space/epsilon/index.html Epsilon Launch Vehicle], IHI Aerospace
{{Expendable launch systems}}
{{Japanese launch systems}}
Category:Space launch vehicles of Japan