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31

New Horizons went into Earth parking orbit first, so it doesn't count. For a suborbital direct ascent trajectory, some early lunar probes (USSR's Luna-1 for example) would hold this record. Otherwise, early vertical research probes included the Blue Scout Junior, one of which reached 44400 km on 1961 Dec 4 (mission O-2) - another may have reached 225000 km ...


21

The EU and ESA are not related. They have different member states, where neither is a subset of the other. The only potential issue is simply economic. If the British exit from the EU results in a depressed UK economy, then they may elect to participate less in ESA.


16

Not sure if this counts, but New Horizons was launched directly into an escape trajectory and did not enter orbit. It made it to Pluto and beyond. From Wikipedia: New Horizons was launched from Cape Canaveral Air Force Station directly into an Earth-and-solar escape trajectory with a speed of about 16.26 kilometers per second That might be considered ...


15

This is a pretty interesting question in retrospect now. When it was asked in 2013, booster re-usablity was just a gleam in SpaceX's eye. The first Falcon 9 attempt to land a booster wasn't until 2015. But clearly SpaceX's pricing was already a problem for ESA, the Falcon 9 is roughly equivalent to the Ariane 5 in launch capacity, but have always been ...


15

I think you already know the answer, it is not really a technical issue, it is (mainly) political. The Germans have experience with liquid engines (they make major parts for the liquid main engine of Ariane 5) and the Italians have experience with solid fuel (they make part of the solid boosters for Ariane 5 and the majority of the solid fueled Vega-rocket). ...


13

The question should be broken in several parts. Why was Cape Canaveral chosen? Why does NASA not relocate somewhere else? What is the gain in terms of payload mass when launching from Kourou? I will not answer the third part since for each launcher and inclination the answer will be slightly different. From Moonport: Cape Canaveral, better known as "...


12

Yes, astronauts do use their legs. In weightlessness, any movement you make (even tiny things like pressing a button) will push you in the opposite direction. At many workstations, footholds are provided. The astronauts use the footholds to hold themselves in place, so they can use both hands for the work they're doing instead of continually needing one ...


11

It appears to match the "X band antenna" on this diagram: (Taken from https://directory.eoportal.org/web/eoportal/satellite-missions/c-missions/copernicus-sentinel-3 -- But they credit ESA for that image) It also matches the general style of at least one example antenna found in a google search for X-band antenna. (X Band Isoflux antenna from https://...


10

Okay, here's the general break down in Solids vs Liquids debate, with a bit of help from Wikipedia, ESA, and NASA: Solids- Solid fueled rockets must be manufactured in a controlled environment. If not constructed properly, they can have impurities resulting in uncontrolled expansions (Explosions). They are safer generally speaking than Liquids, and don't ...


10

From 1985 to 1992, ESA worked on a manned space program, using the Hermes spaceplane (to be launched by the Ariane 5 then in development). This program was cancelled due to rising cost and the loss of a sense of urgency: having an independent manned spaceflight program was seen as non-critical. Basically they had 3 expensive programs: Hermes, Ariane 5 and ...


9

I would like to add my own answer based purely on math, which is not as complex as you may think (but I explain each term and everything else so it looks long). We only need a couple equations. First the Tsiolkovsky Rocket Equation: $V_f = V_e \ln(\displaystyle \frac{m_i}{m_f})$ (Soon, we'll need this rearranged for $m_f$, which is $m_f = \displaystyle \...


9

The effect should be small, but possibly non-zero. There currently exists growing cooperation between EU and ESA. Within the EU-ESA membership agreement, one of the noted obstacles is the membership asymmetry: 2.2. Membership asymmetry At present, 17 EU Member States are Members of ESA. ESA's members include Norway and Switzerland, which are not EU ...


9

Schiaparelli was a test mission. During its descent, it recorded and sent lots of data which was analyzed and gave ESA the information it needed to proceed with the Rosalind Franklin mission.


8

As @Antzi said in his now-deleted answer, initially ExoMars was to be a collaboration between ESA and NASA, with NASA providing the launches. When NASA left the program, ESA sought a new deal, this time with Roscosmos. As of 2009, in April 2018, NASA's Atlas rocket would launch the European Space Agency's long-delayed ExoMars rover and a smaller NASA rover (...


8

I've studied this out, and found a few additional close calls. But there hasn't been any launches out of Europe itself, except for Russia. This is probably because Europe is too population dense to make a launch safe. Some information taken from Gunter's space page. France has launched from Centre interarmées d’essais d’engins spéciaux (CIEES), Hammaguir, ...


8

A single basic radar antenna can't tell you much. The most basic radar setup involves a fixed sending and receiving antenna and some software and drivers. Modern radar then uses a frequency ramp up or "triangular" pulse which it sends from the tx antenna (for example you sweep from 24 to 25 GHz over a short time). Then, you analyse the signal that returns. ...


8

The DSN is used alongside ESTRACK. For Rosetta, for example: NASA’s DSN network has provided continuing, routine support to the Rosetta mission since the start of the mission (see “Tracking the spacecraft following a comet”). Numerous DSN stations – including the three, giant 70m antennas located at Madrid, Spain, Canberra, Australia, and Goldstone, ...


8

Apparently, black was chosen despite its thermal properties. This 2005 paper was written at the end of the assessment phase where technical feasibility of the mission has been demonstrated. It shows several options were studied, including a white shield. Materials with a/e (absorption/emission constant, ed.) close to 1 could also be used. Typically ...


8

Other spacecraft have been closer, but none have carried Sun-facing imagers. Source: The link you provided ("Other spacecraft" is linked to an article about Parker Solar Probe) Q: Or did Parker just not take pics of the Sun yet? A: Yes, or at least not from a distance closer than Solar Orbiter


7

I would love to see/hear about amputees in space, first off. Gives hope to all of us who are not the NORM... However, you would still need the ability to move around the ship without bouncing into controls and knocking into others aboard. In my mind that means the ability to use your legs full range of motion to kick off or slow your momentum down in ...


7

As @nos said, the decision to go with SPARC was made in 1991. There were several reasons (presentation on history of ERC and Leon): ESA performed two architectural studies, evaluating processors such as MIPS, THOR, MC68020, I386, NS32. ESA also invited industry for round-table discussions. Finally, SPARC was selected due to: Open architecture ...


7

Streamlining is not the problem: those fancy-looking outer shells will burn up early on in the re-entry process. The pieces of a satellite that hit the ground are the high-density ones: things like pressurized fuel tanks, thick structural members, and radiothermal generators. If a satellite uses unpressurized maneuvering fuel, has lightweight structural ...


7

Spaceflight Now has a detailed overview of Gaia's launch sequence. There don't seem to be any Earth flybys or gravity assists planned. Just a single orbit around Earth after launch, then the burn to inject Gaia into its L2 transfer trajectory. When it arrives at L2, a delta-V of 180 meters per second inserts Gaia into its orbit around L2. Note that seems to ...


7

The Baltic Sea is far too crowded to make it the range area. At any point of time you can see at least several ships within view distance. For the same reason, while it might seem like the isle of Ibiza would provide 2700km of downrange over the sea, the Mediterrean Sea traffic is so high, it's unlikely to be allowed, plus the range of inclinations is ...


7

Baikonur is definitely less favorable launch site than Guiana, with highly inclined orbits, but that doesn't play such a big role with interplanetary missions as inclination correction on very high orbits is relatively inexpensive. But first, there are simple, direct budget concerns: ExoMars doesn't require the large payload capacity of Arianne (and it's ...


7

After reading @ Saiboogu's answer explaining what this is, I found some additional helpful information. This is an isoflux antenna, designed to provide an approximately constant flux of broadcast signal over the useful transmission footprint on the Earth, from the nadir out to a maximum cone angle of 60 degrees from the nadir as seen by the spacecraft. ...


7

Closer view: (Cropped from here) They are retro-rockets used in the stage separation system. Source A CFD image of the thrusters firing: Source


6

I asked Jim Carpenter, lead scientist for ESA on the Luna 27 lander project, about this. He said that although the plans and protocols for Aurora are still in place, it is currently on hold, outside of the Exomars program. ESA announced the Heracles program a few weeks ago. The winners of that competition will present their plans at the Moon 2020-2030 ...


6

It might be more meaningful to look at Arianespace rather than ESA - Arianespace is the commercial operation (owned ~1/3 by CNES and ~2/3 by various European aerospace firms) which actually operates the launcher. ESA currently gives it a fixed cash payment every year (~100m euro in 2013 & 2014, 145m in 2012, possibly less in 2011). In recent years (...


6

The European Space Agency (ESA) is subject to the Regulations of the European Space Agency. One of these documents is ESA/REG/008 - Rules on Information, Data and Intellectual Property, the goal of which is stated as follows: The Rules on Information, Data and Intellectual Property, as adopted by Council on 19 December 2001 under the reference ESA/C/CLV/...


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